diff --git a/RikaHubbardTestCases/Array_Assertions_Test.java b/RikaHubbardTestCases/Array_Assertions_Test.java
new file mode 100644
index 00000000000..d987dae035c
--- /dev/null
+++ b/RikaHubbardTestCases/Array_Assertions_Test.java
@@ -0,0 +1,19 @@
+package org.assertj.examples;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class ArrayAssertionsTest {
+
+    @Test
+    void shouldAssertArrayProperties() {
+        int[] numbers = {1, 2, 3, 4};
+
+        assertThat(numbers)
+            .hasSize(4)
+            .contains(3)
+            .containsExactly(1, 2, 3, 4)
+            .doesNotContain(5);
+    }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/Exception_Assertions_Test.java b/RikaHubbardTestCases/Exception_Assertions_Test.java
new file mode 100644
index 00000000000..76c9c618e0d
--- /dev/null
+++ b/RikaHubbardTestCases/Exception_Assertions_Test.java
@@ -0,0 +1,17 @@
+package org.assertj.examples;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+public class ExceptionAssertionsTest {
+
+    @Test
+    void shouldAssertExceptionThrown() {
+        assertThatThrownBy(() -> {
+            throw new IllegalArgumentException("Invalid argument");
+        })
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessageContaining("Invalid");
+    }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/IntegerAssert_isNegative_Test.java b/RikaHubbardTestCases/IntegerAssert_isNegative_Test.java
new file mode 100644
index 00000000000..c4bfadd1146
--- /dev/null
+++ b/RikaHubbardTestCases/IntegerAssert_isNegative_Test.java
@@ -0,0 +1,16 @@
+package org.assertj.core.api.integer;
+
+import org.junit.jupiter.api.Test;
+import static org.assertj.core.api.BDDAssertions.then;
+
+class IntegerAssert_isNegative_Test extends BaseTest {
+
+  @Test
+  void should_pass_when_integer_is_negative() {
+    // Given
+    int value = -5;
+
+    // When/then
+    then(value).isNegative();
+  }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/IntegerAssert_isPositive_Test.java b/RikaHubbardTestCases/IntegerAssert_isPositive_Test.java
new file mode 100644
index 00000000000..a5de819f094
--- /dev/null
+++ b/RikaHubbardTestCases/IntegerAssert_isPositive_Test.java
@@ -0,0 +1,16 @@
+package org.assertj.core.api.integer;
+
+import org.junit.jupiter.api.Test;
+import static org.assertj.core.api.BDDAssertions.then;
+
+class IntegerAssert_isPositive_Test {
+
+  @Test
+  void should_pass_when_integer_is_positive() {
+    // GIVEN
+    int value = 42;
+
+    // WHEN/THEN
+    then(value).isPositive();
+  }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/ListAssert_contains_Test.java b/RikaHubbardTestCases/ListAssert_contains_Test.java
new file mode 100644
index 00000000000..9efac05a5c2
--- /dev/null
+++ b/RikaHubbardTestCases/ListAssert_contains_Test.java
@@ -0,0 +1,19 @@
+package org.assertj.core.api.list;
+
+import org.junit.jupiter.api.Test;
+import java.util.Arrays;
+import java.util.List;
+import static org.assertj.core.api.BDDAssertions.then;
+
+
+class ListAssert_contains_Test extends BaseTest {
+
+  @Test
+  void should_pass_when_list_contains_element() {
+    // GIVEN
+    List<String> names = Arrays.asList("Alice", "Bob", "Charlie");
+
+    // WHEN/THEN
+    then(names).contains("Bob");
+  }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/ListAssert_doesNotContain_Test.java b/RikaHubbardTestCases/ListAssert_doesNotContain_Test.java
new file mode 100644
index 00000000000..30d6222d4e6
--- /dev/null
+++ b/RikaHubbardTestCases/ListAssert_doesNotContain_Test.java
@@ -0,0 +1,15 @@
+package org.assertj.core.api.list;
+
+import org.junit.jupiter.api.Test;
+import java.util.Arrays;
+import java.util.List;
+import static org.assertj.core.util.AssertionsUtil.expectAssertionError; 
+ 
+Class ListAssert_doesNotContain_Test {
+
+@Test
+void should_pass_when_list_does_not_contain_element() {
+  List<String> names = Arrays.asList("Alice", "Bob", "Charlie");
+  assertThat(names).doesNotContain("David");
+}
+}
diff --git a/RikaHubbardTestCases/MapAssert_containsKeys_Test.java b/RikaHubbardTestCases/MapAssert_containsKeys_Test.java
new file mode 100644
index 00000000000..e441a11275e
--- /dev/null
+++ b/RikaHubbardTestCases/MapAssert_containsKeys_Test.java
@@ -0,0 +1,18 @@
+package org.assertj.core.api.map;
+
+import org.junit.jupiter.api.Test;
+import java.util.Map;
+import static org.assertj.core.api.BDDAssertions.then;
+
+
+class MapAssert_containsKeys_Test {
+
+  @Test
+  void should_pass_when_map_contains_keys() {
+    
+    Map<String, Integer> ageMap = Map.of("Alice", 30, "Bob", 25);
+
+  
+    then(ageMap).containsKeys("Alice", "Bob");
+  }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/MapAssert_hasSize_Test.java b/RikaHubbardTestCases/MapAssert_hasSize_Test.java
new file mode 100644
index 00000000000..29895e50bf6
--- /dev/null
+++ b/RikaHubbardTestCases/MapAssert_hasSize_Test.java
@@ -0,0 +1,18 @@
+package org.assertj.core.api.map;
+
+import org.junit.jupiter.api.Test;
+import java.util.Map;
+import static org.assertj.core.api.BDDAssertions.then;
+
+
+class MapAssert_hasSize_Test extends BaseTest {
+
+  @Test
+  void should_pass_when_map_has_expected_size() {
+    
+    Map<String, Integer> ageMap = Map.of("Alice", 30, "Bob", 25);
+
+    
+    then(ageMap).hasSize(2);
+  }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/Soft_Assert_Test.java b/RikaHubbardTestCases/Soft_Assert_Test.java
new file mode 100644
index 00000000000..2768a464f0a
--- /dev/null
+++ b/RikaHubbardTestCases/Soft_Assert_Test.java
@@ -0,0 +1,18 @@
+package org.assertj.examples;
+
+import org.assertj.core.api.SoftAssertions;
+import org.junit.jupiter.api.Test;
+
+public class SoftAssertionsTest {
+
+    @Test
+    void shouldAssertMultipleConditionsSoftly() {
+        SoftAssertions softly = new SoftAssertions();
+
+        softly.assertThat("Hello").startsWith("H"); // passes
+        softly.assertThat(42).isGreaterThan(50);    // fails
+        softly.assertThat(true).isFalse();          // fails
+
+        softly.assertAll(); // will show all failed assertions
+    }
+}
\ No newline at end of file
diff --git a/RikaHubbardTestCases/StringAssert_isNotEmpty_Test.java b/RikaHubbardTestCases/StringAssert_isNotEmpty_Test.java
new file mode 100644
index 00000000000..3ba1dd7bcae
--- /dev/null
+++ b/RikaHubbardTestCases/StringAssert_isNotEmpty_Test.java
@@ -0,0 +1,11 @@
+import static org.assertj.core.api.BDDAssertions.then;
+import static org.assertj.core.util.AssertionsUtil.expectAssertionError;
+
+Class StringAssert_isNotEmpty_Test  extends BaseTest {
+
+  @Test
+void should_pass_when_string_is_not_empty() {
+  assertThat("AssertJ").isNotEmpty();
+}
+
+}