diff --git a/week15/3.practice/exercise/ex1.ts b/week15/3.practice/exercise/ex1.ts
new file mode 100644
index 0000000..c8ec209
--- /dev/null
+++ b/week15/3.practice/exercise/ex1.ts
@@ -0,0 +1,53 @@
+/* 원문(en)
+
+Intro:
+
+    We are starting a small community of users. For performance
+    reasons we have decided to store all users right in the code.
+    This way we can provide our developers with more
+    user-interaction opportunities. With user-related data, at least.
+    All the GDPR-related issues will be solved some other day.
+    This would be the base for our future experiments during
+    these exercises.
+
+Exercise:
+
+    Given the data, define the interface "User" and use it accordingly.
+
+*/
+
+
+/*
+    1번
+
+    주어진 데이터에서 'User'라는 이름의 interface를 정의,
+    작성한 인터페이스를 코드 내에서 적절하게 사용하기
+*/
+
+export type User = unknown;
+
+export const users: unknown[] = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    }
+];
+
+export function logPerson(user: unknown) {
+    console.log(` - ${user.name}, ${user.age}`);
+}
+
+console.log('Users:');
+users.forEach(logPerson);
+
+
+/* In case if you are stuck:
+
+// https://www.typescriptlang.org/docs/handbook/2/objects.html
+*/
diff --git a/week15/3.practice/exercise/ex2.ts b/week15/3.practice/exercise/ex2.ts
new file mode 100644
index 0000000..232dadf
--- /dev/null
+++ b/week15/3.practice/exercise/ex2.ts
@@ -0,0 +1,73 @@
+/* 원문(en)
+
+Intro:
+
+    All 2 users liked the idea of the community. We should go
+    forward and introduce some order. We are in Germany after all.
+    Let's add a couple of admins.
+
+    Initially we only had users in the in-memory database. After
+    introducing Admins, we need to fix the types so that
+    everything works well together.
+
+Exercise:
+
+    Type "Person" is missing, please define it and use
+    it in persons array and logPerson function in order to fix
+    all the TS errors.
+
+*/
+
+/*
+    2번
+
+    현재 코드에는 'Person'이라는 Type이 정의(작성)되어 있지 않음
+    따라서 해당 타입을 정의 후, person 배열(array)과 logPerson()에 적용하여
+    TS 에러를 해결하기
+*/
+
+interface User {
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = unknown;
+
+export const persons: User[] /* <- Person[] */ = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    }
+];
+
+export function logPerson(user: User) {
+    console.log(` - ${user.name}, ${user.age}`);
+}
+
+persons.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/types-from-types.html
\ No newline at end of file
diff --git a/week15/3.practice/exercise/ex3.ts b/week15/3.practice/exercise/ex3.ts
new file mode 100644
index 0000000..591ca89
--- /dev/null
+++ b/week15/3.practice/exercise/ex3.ts
@@ -0,0 +1,81 @@
+/* 원문(en)
+
+Intro:
+
+    Since we already have some of the additional
+    information about our users, it's a good idea
+    to output it in a nice way.
+
+Exercise:
+
+    Fix type errors in logPerson function.
+
+    logPerson function should accept both User and Admin
+    and should output relevant information according to
+    the input: occupation for User and role for Admin.
+
+*/
+
+/*
+    3번
+
+    logPerson()의 타입 에러 해결하기
+    logPerson()은 User와 Admin 인터페이스를 
+    모두 인수로 전달받을 수 있어야하고,
+
+    전달받은 인수의 값(input value)에 따라 적절한 값(output value)을 반환해야함
+    ex) User 타입일 경우, occupation 프로퍼티
+    Admin 타입일 경우, role 프로퍼티
+*/
+
+interface User {
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    }
+];
+
+export function logPerson(person: Person) {
+    let additionalInformation: string;
+    if (person.role) {
+        additionalInformation = person.role;
+    } else {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+persons.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/narrowing.html#the-in-operator-narrowing
\ No newline at end of file
diff --git a/week15/3.practice/exercise/ex4.ts b/week15/3.practice/exercise/ex4.ts
new file mode 100644
index 0000000..b53fcb5
--- /dev/null
+++ b/week15/3.practice/exercise/ex4.ts
@@ -0,0 +1,76 @@
+/* 원문(en)
+
+Intro:
+
+    As we introduced "type" to both User and Admin
+    it's now easier to distinguish between them.
+    Once object type checking logic was extracted
+    into separate functions isUser and isAdmin -
+    logPerson function got new type errors.
+
+Exercise:
+
+    Figure out how to help TypeScript understand types in
+    this situation and apply necessary fixes.
+
+*/
+
+/*
+    4번
+
+    문제의 코드에서 TypeScript가 
+    타입을 이해할 수 있도록 코드를 수정해보기
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    { type: 'admin', name: 'Jane Doe', age: 32, role: 'Administrator' },
+    { type: 'user', name: 'Kate Müller', age: 23, occupation: 'Astronaut' },
+    { type: 'admin', name: 'Bruce Willis', age: 64, role: 'World saver' }
+];
+
+export function isAdmin(person: Person) {
+    return person.type === 'admin';
+}
+
+export function isUser(person: Person) {
+    return person.type === 'user';
+}
+
+export function logPerson(person: Person) {
+    let additionalInformation: string = '';
+    if (isAdmin(person)) {
+        additionalInformation = person.role;
+    }
+    if (isUser(person)) {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+console.log('Admins:');
+persons.filter(isAdmin).forEach(logPerson);
+
+console.log();
+
+console.log('Users:');
+persons.filter(isUser).forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/narrowing.html#using-type-predicates
diff --git a/week15/3.practice/exercise/ex5.ts b/week15/3.practice/exercise/ex5.ts
new file mode 100644
index 0000000..12ebda7
--- /dev/null
+++ b/week15/3.practice/exercise/ex5.ts
@@ -0,0 +1,124 @@
+/* 원문(En)
+
+Intro:
+
+    Time to filter the data! In order to be flexible
+    we filter users using a number of criteria and
+    return only those matching all of the criteria.
+    We don't need Admins yet, we only filter Users.
+
+Exercise:
+
+    Without duplicating type structures, modify
+    filterUsers function definition so that we can
+    pass only those criteria which are needed,
+    and not the whole User information as it is
+    required now according to typing.
+
+Higher difficulty bonus exercise:
+
+    Exclude "type" from filter criterias.
+
+*/
+
+/*
+    5번
+
+    타입 구조를 새로 추가 정의하지 않고,
+    filterUsers() 함수 정의(선언부 부분, 파라미터)를 수정하여 
+    필요한 기준(criteria)에만 부합하는 파라미터를 전달할 수 있도록 구현
+
+    * 부가 설명
+    현재 작성된 코드는 전체 사용자 정보(User information)를 받고 있지만, 
+    정말 필요한 기준의 값만 전달할 수 있도록 구현하라는 의미
+
+    ** High difficulty bonus exercise
+    Exclude "type" from filter criterias.
+
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    {
+        type: 'admin',
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        type: 'user',
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        type: 'admin',
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    },
+    {
+        type: 'user',
+        name: 'Wilson',
+        age: 23,
+        occupation: 'Ball'
+    },
+    {
+        type: 'admin',
+        name: 'Agent Smith',
+        age: 23,
+        role: 'Administrator'
+    }
+];
+
+export const isAdmin = (person: Person): person is Admin => person.type === 'admin';
+export const isUser = (person: Person): person is User => person.type === 'user';
+
+export function logPerson(person: Person) {
+    let additionalInformation = '';
+    if (isAdmin(person)) {
+        additionalInformation = person.role;
+    }
+    if (isUser(person)) {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+export function filterUsers(persons: Person[], criteria: User): User[] {
+    return persons.filter(isUser).filter((user) => {
+        const criteriaKeys = Object.keys(criteria) as (keyof User)[];
+        return criteriaKeys.every((fieldName) => {
+            return user[fieldName] === criteria[fieldName];
+        });
+    });
+}
+
+console.log('Users of age 23:');
+
+filterUsers(
+    persons,
+    {
+        age: 23
+    }
+).forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/utility-types.html
+// https://www.typescriptlang.org/docs/handbook/release-notes/typescript-2-8.html#predefined-conditional-types
\ No newline at end of file
diff --git a/week15/3.practice/exercise/ex6.ts b/week15/3.practice/exercise/ex6.ts
new file mode 100644
index 0000000..cf9b30d
--- /dev/null
+++ b/week15/3.practice/exercise/ex6.ts
@@ -0,0 +1,104 @@
+/* 원문(en)
+
+Intro:
+
+    Filtering requirements have grown. We need to be
+    able to filter any kind of Persons.
+
+Exercise:
+
+    Fix typing for the filterPersons so that it can filter users
+    and return User[] when personType='user' and return Admin[]
+    when personType='admin'. Also filterPersons should accept
+    partial User/Admin type according to the personType.
+    `criteria` argument should behave according to the
+    `personType` argument value. `type` field is not allowed in
+    the `criteria` field.
+
+Higher difficulty bonus exercise:
+
+    Implement a function `getObjectKeys()` which returns more
+    convenient result for any argument given, so that you don't
+    need to cast it.
+
+    let criteriaKeys = Object.keys(criteria) as (keyof User)[];
+    -->
+    let criteriaKeys = getObjectKeys(criteria);
+
+*/
+
+/*
+    6번
+
+    filterPersons()를 수정해서 user를 필터링할 수 있고, personType이 'user'일 때는
+    User[]을, personType이 'admin'일 때는 Admin[]을 반환하도록 구현
+
+    또한 filterPersons()는 인수(파라미터) 'personType'에 따라 부분적으로 User 혹은 Admin 타입을 받을 수 있어야함
+
+    criteria 인수는 personType의 인수에 따라 함수의 동작이 달라져야함
+    제약조건: 'type' 필드는 criteria 필드에 허용될 수 없음
+
+    Higher difficulty bonus exercise:(미번역)
+    
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    { type: 'admin', name: 'Jane Doe', age: 32, role: 'Administrator' },
+    { type: 'user', name: 'Kate Müller', age: 23, occupation: 'Astronaut' },
+    { type: 'admin', name: 'Bruce Willis', age: 64, role: 'World saver' },
+    { type: 'user', name: 'Wilson', age: 23, occupation: 'Ball' },
+    { type: 'admin', name: 'Agent Smith', age: 23, role: 'Anti-virus engineer' }
+];
+
+export function logPerson(person: Person) {
+    console.log(
+        ` - ${person.name}, ${person.age}, ${person.type === 'admin' ? person.role : person.occupation}`
+    );
+}
+
+export function filterPersons(persons: Person[], personType: string, criteria: unknown): unknown[] {
+    return persons
+        .filter((person) => person.type === personType)
+        .filter((person) => {
+            let criteriaKeys = Object.keys(criteria) as (keyof Person)[];
+            return criteriaKeys.every((fieldName) => {
+                return person[fieldName] === criteria[fieldName];
+            });
+        });
+}
+
+// 
+export function getObjectKeys(criteria: ) {
+
+}
+
+export const usersOfAge23 = filterPersons(persons, 'user', { age: 23 });
+export const adminsOfAge23 = filterPersons(persons, 'admin', { age: 23 });
+
+console.log('Users of age 23:');
+usersOfAge23.forEach(logPerson);
+
+console.log();
+
+console.log('Admins of age 23:');
+adminsOfAge23.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/functions.html#function-overloads
diff --git a/week15/3.practice/exercise/tsconfig.json b/week15/3.practice/exercise/tsconfig.json
new file mode 100644
index 0000000..1109fb2
--- /dev/null
+++ b/week15/3.practice/exercise/tsconfig.json
@@ -0,0 +1,8 @@
+{
+  "compilerOptions": {    
+    "target": "ESNext",                                  /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */    
+    "strict": true,
+    "noEmitOnError": true,
+    "lib": ["ESNext", "DOM"]
+  }
+}
diff --git a/week15/3.practice/solution/ex1.ts b/week15/3.practice/solution/ex1.ts
new file mode 100644
index 0000000..c795f1c
--- /dev/null
+++ b/week15/3.practice/solution/ex1.ts
@@ -0,0 +1,59 @@
+/* 원문(en)
+
+Intro:
+
+    We are starting a small community of users. For performance
+    reasons we have decided to store all users right in the code.
+    This way we can provide our developers with more
+    user-interaction opportunities. With user-related data, at least.
+    All the GDPR-related issues will be solved some other day.
+    This would be the base for our future experiments during
+    these exercises.
+
+Exercise:
+
+    Given the data, define the interface "User" and use it accordingly.
+
+*/
+
+
+/*
+    1번
+
+    주어진 데이터에서 'User'라는 이름의 interface를 정의,
+    작성한 인터페이스를 코드 내에서 적절하게 사용하기
+*/
+
+export type User = {
+    name: String,
+    age: Number,
+    occupation: String,
+};
+
+export const users: User[] = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    }
+];
+
+export function logPerson(user: User) {
+    console.log(` - ${user.name}, ${user.age}`);
+}
+
+console.log('Users:');
+users.forEach(logPerson);
+
+
+/* In case if you are stuck:
+
+// https://www.typescriptlang.org/docs/handbook/2/objects.html
+*/
+
+// Q. interface와 type의 차이?
\ No newline at end of file
diff --git a/week15/3.practice/solution/ex2.ts b/week15/3.practice/solution/ex2.ts
new file mode 100644
index 0000000..08fd53a
--- /dev/null
+++ b/week15/3.practice/solution/ex2.ts
@@ -0,0 +1,73 @@
+/* 원문(en)
+
+Intro:
+
+    All 2 users liked the idea of the community. We should go
+    forward and introduce some order. We are in Germany after all.
+    Let's add a couple of admins.
+
+    Initially we only had users in the in-memory database. After
+    introducing Admins, we need to fix the types so that
+    everything works well together.
+
+Exercise:
+
+    Type "Person" is missing, please define it and use
+    it in persons array and logPerson function in order to fix
+    all the TS errors.
+
+*/
+
+/*
+    2번
+
+    현재 코드에는 'Person'이라는 Type이 정의(작성)되어 있지 않음(41번 라인)
+    따라서 해당 타입을 정의 후, person 배열(array)과 logPerson()에 적용하여
+    TS 에러를 해결하기
+*/
+
+interface User {
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    }
+];
+
+export function logPerson(person: Person) {
+    console.log(` - ${person.name}, ${person.age}`);
+}
+
+persons.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/types-from-types.html
\ No newline at end of file
diff --git a/week15/3.practice/solution/ex3.ts b/week15/3.practice/solution/ex3.ts
new file mode 100644
index 0000000..6976878
--- /dev/null
+++ b/week15/3.practice/solution/ex3.ts
@@ -0,0 +1,82 @@
+/* 원문(en)
+
+Intro:
+
+    Since we already have some of the additional
+    information about our users, it's a good idea
+    to output it in a nice way.
+
+Exercise:
+
+    Fix type errors in logPerson function.
+
+    logPerson function should accept both User and Admin
+    and should output relevant information according to
+    the input: occupation for User and role for Admin.
+
+*/
+
+/*
+    3번
+
+    logPerson()의 타입 에러 해결하기
+    logPerson()은 User와 Admin 인터페이스를 
+    모두 인수로 전달받을 수 있어야하고,
+
+    전달받은 인수의 값(input value)에 따라 적절한 값(output value)을 반환해야함
+    ex) User 타입일 경우, occupation 프로퍼티
+    Admin 타입일 경우, role 프로퍼티
+*/
+
+interface User {
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    {
+        name: 'Max Mustermann',
+        age: 25,
+        occupation: 'Chimney sweep'
+    },
+    {
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    }
+];
+
+export function logPerson(person: Person) {
+    let additionalInformation: string;
+    // if (person.role) { // Property 'role' does not exist on type 'Person'. -> person으로 전달받은 인수가 User interface 타입일 경우 role 프로퍼티가 존재하지 않을 수 있음
+    if ('role' in person) { // person의 타입을 좁혀서(Narrowing) role이라는 프로퍼티가 존재할 때만 조건식이 성립하도록 변경하여 해결
+        additionalInformation = person.role;
+    } else {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+persons.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/narrowing.html#the-in-operator-narrowing
\ No newline at end of file
diff --git a/week15/3.practice/solution/ex4.ts b/week15/3.practice/solution/ex4.ts
new file mode 100644
index 0000000..f2f6907
--- /dev/null
+++ b/week15/3.practice/solution/ex4.ts
@@ -0,0 +1,78 @@
+/* 원문(en)
+
+Intro:
+
+    As we introduced "type" to both User and Admin
+    it's now easier to distinguish between them.
+    Once object type checking logic was extracted
+    into separate functions isUser and isAdmin -
+    logPerson function got new type errors.
+
+Exercise:
+
+    Figure out how to help TypeScript understand types in
+    this situation and apply necessary fixes.
+
+*/
+
+/*
+    4번
+
+    문제의 코드에서 TypeScript가 
+    타입을 이해할 수 있도록 코드를 수정해보기
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    { type: 'admin', name: 'Jane Doe', age: 32, role: 'Administrator' },
+    { type: 'user', name: 'Kate Müller', age: 23, occupation: 'Astronaut' },
+    { type: 'admin', name: 'Bruce Willis', age: 64, role: 'World saver' }
+];
+
+export function isAdmin(person: Person): person is Admin // 반환 타입으로 타입 예측자(type predicate)를 적용하여 true/false 뿐만 아니라, 
+                                                        // TS 타입 검사기에게 person 객체가 'Admin'타입임을 알려주게 되고, true를 반환할 때, person 객체가 Admin 타입으로 변환됨
+{
+    return person.type === 'admin';
+}
+
+export function isUser(person: Person): person is User {
+    return person.type === 'user';
+}
+
+export function logPerson(person: Person) {
+    let additionalInformation: string = '';
+    if (isAdmin(person)) { // 
+        additionalInformation = person.role; // Property 'role' does not exist on type 'Person' & 'User' -> role 프로퍼티는 User 인터페이스 타입에 존재하지 않을 수 있음
+    }
+    if (isUser(person)) {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+console.log('Admins:');
+persons.filter(isAdmin).forEach(logPerson);
+
+console.log();
+
+console.log('Users:');
+persons.filter(isUser).forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/narrowing.html#using-type-predicates
diff --git a/week15/3.practice/solution/ex5.ts b/week15/3.practice/solution/ex5.ts
new file mode 100644
index 0000000..71ee139
--- /dev/null
+++ b/week15/3.practice/solution/ex5.ts
@@ -0,0 +1,125 @@
+/* 원문(en)
+
+Intro:
+
+    Filtering requirements have grown. We need to be
+    able to filter any kind of Persons.
+
+Exercise:
+
+    Fix typing for the filterPersons so that it can filter users
+    and return User[] when personType='user' and return Admin[]
+    when personType='admin'. Also filterPersons should accept
+    partial User/Admin type according to the personType.
+    `criteria` argument should behave according to the
+    `personType` argument value. `type` field is not allowed in
+    the `criteria` field.
+
+Higher difficulty bonus exercise:
+
+    Implement a function `getObjectKeys()` which returns more
+    convenient result for any argument given, so that you don't
+    need to cast it.
+
+    let criteriaKeys = Object.keys(criteria) as (keyof User)[];
+    -->
+    let criteriaKeys = getObjectKeys(criteria);
+
+*/
+
+/*
+    6번
+
+    filterPersons()를 수정해서 user를 필터링할 수 있고, personType이 'user'일 때는
+    User[]을, personType이 'admin'일 때는 Admin[]을 반환하도록 구현
+
+    또한 filterPersons()는 인수(파라미터) 'personType'에 따라 부분적으로 User 혹은 Admin 타입을 받을 수 있어야함
+
+    criteria 인수는 personType의 인수에 따라 함수의 동작이 달라져야함
+    제약조건: 'type' 필드는 criteria 필드에 허용될 수 없음
+
+    Higher difficulty bonus exercise:(미번역)
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    {
+        type: 'admin',
+        name: 'Jane Doe',
+        age: 32,
+        role: 'Administrator'
+    },
+    {
+        type: 'user',
+        name: 'Kate Müller',
+        age: 23,
+        occupation: 'Astronaut'
+    },
+    {
+        type: 'admin',
+        name: 'Bruce Willis',
+        age: 64,
+        role: 'World saver'
+    },
+    {
+        type: 'user',
+        name: 'Wilson',
+        age: 23,
+        occupation: 'Ball'
+    },
+    {
+        type: 'admin',
+        name: 'Agent Smith',
+        age: 23,
+        role: 'Administrator'
+    }
+];
+
+export const isAdmin = (person: Person): person is Admin => person.type === 'admin';
+export const isUser = (person: Person): person is User => person.type === 'user';
+
+export function logPerson(person: Person) {
+    let additionalInformation = '';
+    if (isAdmin(person)) {
+        additionalInformation = person.role;
+    }
+    if (isUser(person)) {
+        additionalInformation = person.occupation;
+    }
+    console.log(` - ${person.name}, ${person.age}, ${additionalInformation}`);
+}
+
+// Partial로 해결
+export function filterUsers(persons: Person[], criteria: Partial<User>): User[] {
+    return persons.filter(isUser).filter((user) => {
+        const criteriaKeys = Object.keys(criteria) as (keyof User)[];
+        return criteriaKeys.every((fieldName) => {
+            return user[fieldName] === criteria[fieldName];
+        });
+    });
+}
+
+console.log('Users of age 23:');
+
+filterUsers(
+    persons,
+    {
+        age: 23
+    }
+).forEach(logPerson);
\ No newline at end of file
diff --git a/week15/3.practice/solution/ex6.ts b/week15/3.practice/solution/ex6.ts
new file mode 100644
index 0000000..f8dd6f8
--- /dev/null
+++ b/week15/3.practice/solution/ex6.ts
@@ -0,0 +1,108 @@
+/* 원문(en)
+
+Intro:
+
+    Filtering requirements have grown. We need to be
+    able to filter any kind of Persons.
+
+Exercise:
+
+    Fix typing for the filterPersons so that it can filter users
+    and return User[] when personType='user' and return Admin[]
+    when personType='admin'. Also filterPersons should accept
+    partial User/Admin type according to the personType.
+    `criteria` argument should behave according to the
+    `personType` argument value. `type` field is not allowed in
+    the `criteria` field.
+
+Higher difficulty bonus exercise:
+
+    Implement a function `getObjectKeys()` which returns more
+    convenient result for any argument given, so that you don't
+    need to cast it.
+
+    let criteriaKeys = Object.keys(criteria) as (keyof User)[];
+    -->
+    let criteriaKeys = getObjectKeys(criteria);
+
+*/
+
+/*
+    6번
+
+    filterPersons()를 수정해서 user를 필터링할 수 있고, personType이 'user'일 때는
+    User[]을, personType이 'admin'일 때는 Admin[]을 반환하도록 구현
+
+    또한 filterPersons()는 인수(파라미터) 'personType'에 따라 부분적으로 User 타입을 받거나, Admin 타입을 받을 수도 있어야함(오버로딩 개념 활용)
+
+    criteria 인수는 personType의 인수에 따라 함수의 동작이 달라져야함
+    제약조건: 'type' 필드는 criteria 필드에 허용될 수 없음
+
+    Higher difficulty bonus exercise:(미번역)
+
+*/
+
+interface User {
+    type: 'user';
+    name: string;
+    age: number;
+    occupation: string;
+}
+
+interface Admin {
+    type: 'admin';
+    name: string;
+    age: number;
+    role: string;
+}
+
+export type Person = User | Admin;
+
+export const persons: Person[] = [
+    { type: 'user', name: 'Max Mustermann', age: 25, occupation: 'Chimney sweep' },
+    { type: 'admin', name: 'Jane Doe', age: 32, role: 'Administrator' },
+    { type: 'user', name: 'Kate Müller', age: 23, occupation: 'Astronaut' },
+    { type: 'admin', name: 'Bruce Willis', age: 64, role: 'World saver' },
+    { type: 'user', name: 'Wilson', age: 23, occupation: 'Ball' },
+    { type: 'admin', name: 'Agent Smith', age: 23, role: 'Anti-virus engineer' }
+];
+
+export function logPerson(person: Person) {
+    console.log(
+        ` - ${person.name}, ${person.age}, ${person.type === 'admin' ? person.role : person.occupation}`
+    );
+}
+
+// ex) filterPersons(persons, 'user', { age: 23 }); // admin이 아닌 user 리스트에서 age가 23인 user만 필터링
+export function filterPersons(persons: Person[], personType: string, criteria: object): Person[] {
+    return persons
+        .filter((person) => person.type === personType) // personType('user' or 'admin')으로 user와 admin 중 하나로 필터링
+        .filter((person) => {
+            let criteriaKeys = getObjectKey(criteria);// 인수 criteria의 타입을 object로 하면 이 줄은 해결 가능하나, 아래의 에러 발생
+            return criteriaKeys.every((fieldName) => {
+                return person[fieldName] === criteria[fieldName];
+                // Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'Person'.
+                // No index signature with a parameter of type 'string' was found on type '{}'.
+            });
+        });
+}
+
+// const getObjectKeys = <T>(obj: T) => Object.keys(obj) as (keyof T)[];
+export function getObjectKey<T extends object>(criteria: T) {
+    return Object.keys(criteria) as (keyof T)[]; // as (keyof T)[]을 뒤에 추가하지 않으면 filterPersons()의 최종 return부분에서 하단(Line86~)에 작성된(ELement implicitly~)에러 발생
+                                    // 다른 해결 방법으로는 User, Admin 인터페이스의 필드 부분에 각각 인덱스 시그니처인 [key: string]: string | number;를 추가하여 해결 가능
+}
+
+export const usersOfAge23 = filterPersons(persons, 'user', { age: 23 });
+export const adminsOfAge23 = filterPersons(persons, 'admin', { age: 23 });
+
+console.log('Users of age 23:');
+usersOfAge23.forEach(logPerson);
+
+console.log();
+
+console.log('Admins of age 23:');
+adminsOfAge23.forEach(logPerson);
+
+// In case if you are stuck:
+// https://www.typescriptlang.org/docs/handbook/2/functions.html#function-overloads
diff --git a/week15/sample-spring-app-gradle/.gitattributes b/week15/sample-spring-app-gradle/.gitattributes
new file mode 100644
index 0000000..8af972c
--- /dev/null
+++ b/week15/sample-spring-app-gradle/.gitattributes
@@ -0,0 +1,3 @@
+/gradlew text eol=lf
+*.bat text eol=crlf
+*.jar binary
diff --git a/week15/sample-spring-app-gradle/.gitignore b/week15/sample-spring-app-gradle/.gitignore
new file mode 100644
index 0000000..c2065bc
--- /dev/null
+++ b/week15/sample-spring-app-gradle/.gitignore
@@ -0,0 +1,37 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
diff --git a/week15/sample-spring-app-gradle/Dockerfile b/week15/sample-spring-app-gradle/Dockerfile
new file mode 100644
index 0000000..4e28afa
--- /dev/null
+++ b/week15/sample-spring-app-gradle/Dockerfile
@@ -0,0 +1,7 @@
+FROM openjdk:17-jdk-alpine
+ARG JAR_FILE=/build/libs/*.jar
+COPY ${JAR_FILE} /app.jar
+ENTRYPOINT ["java", "-jar","app.jar"]
+
+#docker tag local-image:tagname new-repo:tagname
+#docker push new-repo:tagname
diff --git a/week15/sample-spring-app-gradle/README.md b/week15/sample-spring-app-gradle/README.md
new file mode 100644
index 0000000..dd47bbc
--- /dev/null
+++ b/week15/sample-spring-app-gradle/README.md
@@ -0,0 +1 @@
+# sample-spring-app-gradle
diff --git a/week15/sample-spring-app-gradle/SD-LEESEUNGJUN-rsa-key.pem b/week15/sample-spring-app-gradle/SD-LEESEUNGJUN-rsa-key.pem
new file mode 100644
index 0000000..01d573a
--- /dev/null
+++ b/week15/sample-spring-app-gradle/SD-LEESEUNGJUN-rsa-key.pem
@@ -0,0 +1,27 @@
+-----BEGIN RSA PRIVATE KEY-----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+-----END RSA PRIVATE KEY-----
\ No newline at end of file
diff --git a/week15/sample-spring-app-gradle/build.gradle b/week15/sample-spring-app-gradle/build.gradle
new file mode 100644
index 0000000..0d86530
--- /dev/null
+++ b/week15/sample-spring-app-gradle/build.gradle
@@ -0,0 +1,28 @@
+plugins {
+	id 'java'
+	id 'org.springframework.boot' version '3.3.4'
+	id 'io.spring.dependency-management' version '1.1.6'
+}
+
+group = 'com.example'
+version = '0.0.1-SNAPSHOT'
+
+java {
+	toolchain {
+		languageVersion = JavaLanguageVersion.of(17)
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}
diff --git a/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.jar b/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..a4b76b9
Binary files /dev/null and b/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.properties b/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..df97d72
--- /dev/null
+++ b/week15/sample-spring-app-gradle/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.10.2-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/week15/sample-spring-app-gradle/gradlew b/week15/sample-spring-app-gradle/gradlew
new file mode 100755
index 0000000..f5feea6
--- /dev/null
+++ b/week15/sample-spring-app-gradle/gradlew
@@ -0,0 +1,252 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s
+' "$PWD" ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/week15/sample-spring-app-gradle/gradlew.bat b/week15/sample-spring-app-gradle/gradlew.bat
new file mode 100644
index 0000000..9d21a21
--- /dev/null
+++ b/week15/sample-spring-app-gradle/gradlew.bat
@@ -0,0 +1,94 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/week15/sample-spring-app-gradle/settings.gradle b/week15/sample-spring-app-gradle/settings.gradle
new file mode 100644
index 0000000..0a383dd
--- /dev/null
+++ b/week15/sample-spring-app-gradle/settings.gradle
@@ -0,0 +1 @@
+rootProject.name = 'demo'
diff --git a/week15/sample-spring-app-gradle/src/main/java/com/example/demo/DemoApplication.java b/week15/sample-spring-app-gradle/src/main/java/com/example/demo/DemoApplication.java
new file mode 100644
index 0000000..64b538a
--- /dev/null
+++ b/week15/sample-spring-app-gradle/src/main/java/com/example/demo/DemoApplication.java
@@ -0,0 +1,13 @@
+package com.example.demo;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class DemoApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(DemoApplication.class, args);
+	}
+
+}
diff --git a/week15/sample-spring-app-gradle/src/main/java/com/example/demo/HelloController.java b/week15/sample-spring-app-gradle/src/main/java/com/example/demo/HelloController.java
new file mode 100644
index 0000000..ee21c29
--- /dev/null
+++ b/week15/sample-spring-app-gradle/src/main/java/com/example/demo/HelloController.java
@@ -0,0 +1,13 @@
+package com.example.demo;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+public class HelloController {
+
+    @GetMapping("/hello")
+    public String getHello() {
+        return "Hello!";
+    }
+}
\ No newline at end of file
diff --git a/week15/sample-spring-app-gradle/src/main/resources/application.properties b/week15/sample-spring-app-gradle/src/main/resources/application.properties
new file mode 100644
index 0000000..2109a44
--- /dev/null
+++ b/week15/sample-spring-app-gradle/src/main/resources/application.properties
@@ -0,0 +1 @@
+spring.application.name=demo
diff --git a/week15/sample-spring-app-gradle/src/test/java/com/example/demo/DemoApplicationTests.java b/week15/sample-spring-app-gradle/src/test/java/com/example/demo/DemoApplicationTests.java
new file mode 100644
index 0000000..2778a6a
--- /dev/null
+++ b/week15/sample-spring-app-gradle/src/test/java/com/example/demo/DemoApplicationTests.java
@@ -0,0 +1,13 @@
+package com.example.demo;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class DemoApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}
diff --git a/week15/sonarqube/sonar-demo/.gitattributes b/week15/sonarqube/sonar-demo/.gitattributes
new file mode 100644
index 0000000..8af972c
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/.gitattributes
@@ -0,0 +1,3 @@
+/gradlew text eol=lf
+*.bat text eol=crlf
+*.jar binary
diff --git a/week15/sonarqube/sonar-demo/.gitignore b/week15/sonarqube/sonar-demo/.gitignore
new file mode 100644
index 0000000..c2065bc
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/.gitignore
@@ -0,0 +1,37 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+bin/
+!**/src/main/**/bin/
+!**/src/test/**/bin/
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+!**/src/main/**/out/
+!**/src/test/**/out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/
diff --git a/week15/sonarqube/sonar-demo/build.gradle b/week15/sonarqube/sonar-demo/build.gradle
new file mode 100644
index 0000000..ac5d109
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/build.gradle
@@ -0,0 +1,29 @@
+plugins {
+	id 'java'
+	id 'org.springframework.boot' version '3.4.4'
+	id 'io.spring.dependency-management' version '1.1.7'
+    id 'org.sonarqube' version '6.0.1.5171'
+}
+
+group = 'dev.sonar'
+version = '0.0.1-SNAPSHOT'
+
+java {
+	toolchain {
+		languageVersion = JavaLanguageVersion.of(17)
+	}
+}
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter'
+	testImplementation 'org.springframework.boot:spring-boot-starter-test'
+	testRuntimeOnly 'org.junit.platform:junit-platform-launcher'
+}
+
+tasks.named('test') {
+	useJUnitPlatform()
+}
diff --git a/week15/sonarqube/sonar-demo/docker-compose.yml b/week15/sonarqube/sonar-demo/docker-compose.yml
new file mode 100644
index 0000000..ba3801d
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/docker-compose.yml
@@ -0,0 +1,36 @@
+services:
+    sonarqube:
+        image: sonarqube:10.6-community # 소나큐브 커뮤니티 버전 이미지를 활용
+        depends_on:
+            - sonar_db # sonar_db라는 이름의 service 식별자에 의존, 해당 의존성을 가진 이미지 기반의 컨테이너가 먼저 실행 되어야 함
+        environment: # DB 연결 설정 정보
+            SONAR_JDBC_URL: jdbc:postgresql://sonar_db:5432/sonar
+            SONAR_JDBC_USERNAME: sonar
+            SONAR_JDBC_PASSWORD: sonar
+        ports:
+            - "9000:9000"
+        volumes: # SQ 서버에서 볼륨을 통해 실행과정에서 발생하는 데이터들을 관리,저장할 디렉토리 경로
+            - sonarqube_conf:/opt/sonarqube/conf
+            - sonarqube_data:/opt/sonarqube/data
+            - sonarqube_extensions:/opt/sonarqube/extensions
+            - sonarqube_logs:/opt/sonarqube/logs
+            - sonarqube_temp:/opt/sonarqube/temp
+
+    sonar_db: # SQ 서버가 활용할 DBMS 설정
+        image: postgres:16
+        environment:
+            POSTGRES_USER: sonar
+            POSTGRES_PASSWORD: sonar
+            POSTGRES_DB: sonar
+        volumes:
+            - sonar_db:/var/lib/postgresql
+            - sonar_db_data:/var/lib/postgresql/data
+
+volumes:
+    sonarqube_conf:
+    sonarqube_data:
+    sonarqube_extensions:
+    sonarqube_logs:
+    sonarqube_temp:
+    sonar_db:
+    sonar_db_data:
diff --git a/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.jar b/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..9bbc975
Binary files /dev/null and b/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.properties b/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..37f853b
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.13-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/week15/sonarqube/sonar-demo/gradlew b/week15/sonarqube/sonar-demo/gradlew
new file mode 100755
index 0000000..faf9300
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/gradlew
@@ -0,0 +1,251 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/week15/sonarqube/sonar-demo/gradlew.bat b/week15/sonarqube/sonar-demo/gradlew.bat
new file mode 100644
index 0000000..9d21a21
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/gradlew.bat
@@ -0,0 +1,94 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/week15/sonarqube/sonar-demo/index.html b/week15/sonarqube/sonar-demo/index.html
new file mode 100644
index 0000000..2abe342
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/index.html
@@ -0,0 +1,81 @@
+<!DOCTYPE html>
+<html lang="ko">
+
+<head>
+    <meta charset="UTF-8">
+    <title>Markdown Render</title>
+
+    <!-- ✨ GitHub 스타일 마크다운 CSS -->
+    <link rel="stylesheet"
+        href="https://cdnjs.cloudflare.com/ajax/libs/github-markdown-css/5.2.0/github-markdown.min.css">
+
+    <!-- ✨ 코드 하이라이팅 스타일 (GitHub 테마) -->
+    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.8.0/styles/github.min.css">
+
+    <!-- highlight.js core -->
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.8.0/highlight.min.js"></script>
+    <!-- TypeScript 하이라이트 지원 -->
+    <script src="https://cdnjs.cloudflare.com/ajax/libs/highlight.js/11.8.0/languages/typescript.min.js"></script>
+
+    <!-- 자동 하이라이트 실행 -->
+    <script>hljs.highlightAll();</script>
+
+    <!-- 기본 여백 & 폰트 스타일 -->
+    <style>
+        body {
+            font-family: 'Segoe UI', sans-serif;
+            display: flex;
+            justify-content: center;
+            background: #f6f8fa;
+            padding: 40px;
+        }
+
+        .markdown-body {
+            max-width: 800px;
+            padding: 40px;
+            background: white;
+            border-radius: 12px;
+            box-shadow: 0 0 10px rgba(0, 0, 0, 0.05);
+        }
+    </style>
+</head>
+
+<body>
+
+    <article class="markdown-body">
+
+        <p>객체 타입에도 유니언과 내로잉을 적용하여 잠재적 에러를 줄이고 코드의 안전성을 높일 수 있습니다.</p>
+
+        <h4>객체 타입에 유니언 적용하기</h4>
+
+        <code>
+type CookieWithCompany = {
+name: string;
+company: string;
+}
+
+type CookieWithTaste = {
+name: string;
+taste: string;
+}
+
+type Cookie = CookieWithCompany | CookieWithTaste;
+
+const firstCookie: Cookie = Math.random() > 0.5
+? { name: 'OREO', company: 'Nabisco' }
+: { name: 'OREO', taste: 'Choco' };
+
+firstCookie.name; // ✅ OK
+firstCookie.company; // ❌ ERROR
+if ('company' in firstCookie) {
+firstCookie.company;
+} else {
+firstCookie.taste;
+}
+        </code>
+
+
+    </article>
+</body>
+
+</html>
\ No newline at end of file
diff --git a/week15/sonarqube/sonar-demo/settings.gradle b/week15/sonarqube/sonar-demo/settings.gradle
new file mode 100644
index 0000000..f2f2bfc
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/settings.gradle
@@ -0,0 +1 @@
+rootProject.name = 'sonar-demo'
diff --git a/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex1.java b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex1.java
new file mode 100644
index 0000000..1bf7c48
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex1.java
@@ -0,0 +1,23 @@
+
+package dev.sonar;
+
+import java.util.logging.Logger;
+
+public class Ex1 {
+
+    Logger logger = Logger.getLogger("Ex1");
+
+    void run() throws InterruptedException {
+        boolean flag = true;
+        int a = 1;
+
+        while (flag) {
+            logger.info("Hello!");
+            Thread.sleep(5000);
+
+            if (a == 1) {
+                flag = false;
+            }
+        }
+    }
+}
diff --git a/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex2.java b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex2.java
new file mode 100644
index 0000000..29aada1
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/Ex2.java
@@ -0,0 +1,4 @@
+package dev.sonar;
+
+public class Ex2 {
+}
diff --git a/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/SonarDemoApplication.java b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/SonarDemoApplication.java
new file mode 100644
index 0000000..ee0561b
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/src/main/java/dev/sonar/SonarDemoApplication.java
@@ -0,0 +1,13 @@
+package dev.sonar;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class SonarDemoApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(SonarDemoApplication.class, args);
+	}
+
+}
diff --git a/week15/sonarqube/sonar-demo/src/main/resources/application.properties b/week15/sonarqube/sonar-demo/src/main/resources/application.properties
new file mode 100644
index 0000000..3c9e52f
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/src/main/resources/application.properties
@@ -0,0 +1 @@
+spring.application.name=sonar-demo
diff --git a/week15/sonarqube/sonar-demo/src/test/java/dev/sonar/SonarDemoApplicationTests.java b/week15/sonarqube/sonar-demo/src/test/java/dev/sonar/SonarDemoApplicationTests.java
new file mode 100644
index 0000000..1b80a7f
--- /dev/null
+++ b/week15/sonarqube/sonar-demo/src/test/java/dev/sonar/SonarDemoApplicationTests.java
@@ -0,0 +1,13 @@
+package dev.sonar;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class SonarDemoApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}