diff --git a/.travis.yml b/.travis.yml index aac6a7a..34bb406 100644 --- a/.travis.yml +++ b/.travis.yml @@ -3,4 +3,8 @@ language: java sudo: false notifications: - email: false \ No newline at end of file + email: false + +env: + - TEST_DIR=ThreadPool +script: cd $TEST_DIR && ./gradlew clean check \ No newline at end of file diff --git a/ThreadPool/build.gradle b/ThreadPool/build.gradle new file mode 100644 index 0000000..9c74932 --- /dev/null +++ b/ThreadPool/build.gradle @@ -0,0 +1,15 @@ +group 'ru.spbau.dkaznacheev' +version '1.0-SNAPSHOT' + +apply plugin: 'java' + +sourceCompatibility = 1.8 + +repositories { + mavenCentral() +} + +dependencies { + testCompile group: 'junit', name: 'junit', version: '4.12' + compile group: 'org.jetbrains', name: 'annotations', version: '13.0' +} \ No newline at end of file diff --git a/ThreadPool/gradle/wrapper/gradle-wrapper.jar b/ThreadPool/gradle/wrapper/gradle-wrapper.jar new file mode 100644 index 0000000..f90ee89 Binary files /dev/null and b/ThreadPool/gradle/wrapper/gradle-wrapper.jar differ diff --git a/ThreadPool/gradle/wrapper/gradle-wrapper.properties b/ThreadPool/gradle/wrapper/gradle-wrapper.properties new file mode 100644 index 0000000..9b18b37 --- /dev/null +++ b/ThreadPool/gradle/wrapper/gradle-wrapper.properties @@ -0,0 +1,6 @@ +#Fri Mar 09 02:05:00 MSK 2018 +distributionBase=GRADLE_USER_HOME +distributionPath=wrapper/dists +zipStoreBase=GRADLE_USER_HOME +zipStorePath=wrapper/dists +distributionUrl=https\://services.gradle.org/distributions/gradle-3.5-rc-2-all.zip diff --git a/ThreadPool/gradlew b/ThreadPool/gradlew new file mode 100755 index 0000000..4453cce --- /dev/null +++ b/ThreadPool/gradlew @@ -0,0 +1,172 @@ +#!/usr/bin/env sh + +############################################################################## +## +## Gradle start up script for UN*X +## +############################################################################## + +# Attempt to set APP_HOME +# Resolve links: $0 may be a link +PRG="$0" +# Need this for relative symlinks. +while [ -h "$PRG" ] ; do + ls=`ls -ld "$PRG"` + link=`expr "$ls" : '.*-> \(.*\)$'` + if expr "$link" : '/.*' > /dev/null; then + PRG="$link" + else + PRG=`dirname "$PRG"`"/$link" + fi +done +SAVED="`pwd`" +cd "`dirname \"$PRG\"`/" >/dev/null +APP_HOME="`pwd -P`" +cd "$SAVED" >/dev/null + +APP_NAME="Gradle" +APP_BASE_NAME=`basename "$0"` + +# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script. +DEFAULT_JVM_OPTS="" + +# Use the maximum available, or set MAX_FD != -1 to use that value. +MAX_FD="maximum" + +warn ( ) { + echo "$*" +} + +die ( ) { + echo + echo "$*" + echo + exit 1 +} + +# OS specific support (must be 'true' or 'false'). +cygwin=false +msys=false +darwin=false +nonstop=false +case "`uname`" in + CYGWIN* ) + cygwin=true + ;; + Darwin* ) + darwin=true + ;; + MINGW* ) + msys=true + ;; + NONSTOP* ) + nonstop=true + ;; +esac + +CLASSPATH=$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: $JAVA_HOME + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." + fi +else + JAVACMD="java" + which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. + +Please set the JAVA_HOME variable in your environment to match the +location of your Java installation." +fi + +# Increase the maximum file descriptors if we can. +if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then + MAX_FD_LIMIT=`ulimit -H -n` + if [ $? -eq 0 ] ; then + if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then + MAX_FD="$MAX_FD_LIMIT" + fi + ulimit -n $MAX_FD + if [ $? -ne 0 ] ; then + warn "Could not set maximum file descriptor limit: $MAX_FD" + fi + else + warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT" + fi +fi + +# For Darwin, add options to specify how the application appears in the dock +if $darwin; then + GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\"" +fi + +# For Cygwin, switch paths to Windows format before running java +if $cygwin ; then + APP_HOME=`cygpath --path --mixed "$APP_HOME"` + CLASSPATH=`cygpath --path --mixed "$CLASSPATH"` + JAVACMD=`cygpath --unix "$JAVACMD"` + + # We build the pattern for arguments to be converted via cygpath + ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null` + SEP="" + for dir in $ROOTDIRSRAW ; do + ROOTDIRS="$ROOTDIRS$SEP$dir" + SEP="|" + done + OURCYGPATTERN="(^($ROOTDIRS))" + # Add a user-defined pattern to the cygpath arguments + if [ "$GRADLE_CYGPATTERN" != "" ] ; then + OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)" + fi + # Now convert the arguments - kludge to limit ourselves to /bin/sh + i=0 + for arg in "$@" ; do + CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -` + CHECK2=`echo "$arg"|egrep -c "^-"` ### Determine if an option + + if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then ### Added a condition + eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"` + else + eval `echo args$i`="\"$arg\"" + fi + i=$((i+1)) + done + case $i in + (0) set -- ;; + (1) set -- "$args0" ;; + (2) set -- "$args0" "$args1" ;; + (3) set -- "$args0" "$args1" "$args2" ;; + (4) set -- "$args0" "$args1" "$args2" "$args3" ;; + (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;; + (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;; + (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;; + (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;; + (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;; + esac +fi + +# Escape application args +save ( ) { + for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done + echo " " +} +APP_ARGS=$(save "$@") + +# Collect all arguments for the java command, following the shell quoting and substitution rules +eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS" + +# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong +if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then + cd "$(dirname "$0")" +fi + +exec "$JAVACMD" "$@" diff --git a/ThreadPool/gradlew.bat b/ThreadPool/gradlew.bat new file mode 100644 index 0000000..f955316 --- /dev/null +++ b/ThreadPool/gradlew.bat @@ -0,0 +1,84 @@ +@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=. +set APP_BASE_NAME=%~n0 +set APP_HOME=%DIRNAME% + +@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= + +@rem Find java.exe +if defined JAVA_HOME goto findJavaFromJavaHome + +set JAVA_EXE=java.exe +%JAVA_EXE% -version >NUL 2>&1 +if "%ERRORLEVEL%" == "0" goto init + +echo. +echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:findJavaFromJavaHome +set JAVA_HOME=%JAVA_HOME:"=% +set JAVA_EXE=%JAVA_HOME%/bin/java.exe + +if exist "%JAVA_EXE%" goto init + +echo. +echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% +echo. +echo Please set the JAVA_HOME variable in your environment to match the +echo location of your Java installation. + +goto fail + +:init +@rem Get command-line arguments, handling Windows variants + +if not "%OS%" == "Windows_NT" goto win9xME_args + +:win9xME_args +@rem Slurp the command line arguments. +set CMD_LINE_ARGS= +set _SKIP=2 + +:win9xME_args_slurp +if "x%~1" == "x" goto execute + +set CMD_LINE_ARGS=%* + +: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 %CMD_LINE_ARGS% + +:end +@rem End local scope for the variables with windows NT shell +if "%ERRORLEVEL%"=="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! +if not "" == "%GRADLE_EXIT_CONSOLE%" exit 1 +exit /b 1 + +:mainEnd +if "%OS%"=="Windows_NT" endlocal + +:omega diff --git a/ThreadPool/settings.gradle b/ThreadPool/settings.gradle new file mode 100644 index 0000000..667d157 --- /dev/null +++ b/ThreadPool/settings.gradle @@ -0,0 +1,3 @@ +rootProject.name = 'ThreadPool' +rootProject.name = 'ThreadPool' + diff --git a/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFuture.java b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFuture.java new file mode 100644 index 0000000..e556bde --- /dev/null +++ b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFuture.java @@ -0,0 +1,27 @@ +package ru.spbau.dkaznacheev.threadpool; + +import java.util.function.Function; + +public interface LightFuture { + + /** + * Returns whether a computation is completed. + * @return whether a computation is completed + */ + boolean isReady(); + + /** + * Returns the result of the computation, if it is not completed, this method blocks the execution. + * @return result of the computation + * @throws LightFutureException if an exception occurred during a computation + */ + T get() throws LightFutureException; + + /** + * Applies the result of current computation to another and returns another computation's LightFuture. + * @param function the function to compute with this LightFuture's result + * @param type that the function returns + * @return the result of the function + */ + LightFuture thenApply(Function function); +} diff --git a/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFutureException.java b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFutureException.java new file mode 100644 index 0000000..ef84e3f --- /dev/null +++ b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/LightFutureException.java @@ -0,0 +1,7 @@ +package ru.spbau.dkaznacheev.threadpool; + +/** + * An Exception that is thrown when a computation in ThreadPool throws an Exception. + */ +public class LightFutureException extends RuntimeException { +} diff --git a/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPool.java b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPool.java new file mode 100644 index 0000000..4a49870 --- /dev/null +++ b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPool.java @@ -0,0 +1,21 @@ +package ru.spbau.dkaznacheev.threadpool; + +import java.util.function.Supplier; + +/** + * ThreadPool interface. It is capable of adding tasks to it and shutting down all of current workers. + */ +public interface ThreadPool { + /** + * Adds a task to the pool, returning a LightFuture object. + * @param supplier supplier for the computation + * @param type of the result + * @return LightFuture object that will contain the result of computation + */ + LightFuture addTask(Supplier supplier); + + /** + * Shuts down all of its current workers. + */ + void shutdown() throws InterruptedException; +} diff --git a/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolImpl.java b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolImpl.java new file mode 100644 index 0000000..e15c12e --- /dev/null +++ b/ThreadPool/src/main/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolImpl.java @@ -0,0 +1,195 @@ +package ru.spbau.dkaznacheev.threadpool; + +import org.jetbrains.annotations.NotNull; + +import java.util.LinkedList; +import java.util.List; +import java.util.Queue; +import java.util.function.Function; +import java.util.function.Supplier; + +/** + * An implementation of ThreadPool based on queue of jobs that are executed by workers. + */ +public class ThreadPoolImpl implements ThreadPool { + + /** + * A queue of jobs. + */ + private final Queue> queue = new LinkedList<>(); + + /** + * The workers of the pool. + * ThreadPool is created with a fixed number of workers. + */ + private final Thread[] workers; + + public ThreadPoolImpl(int poolSize) { + workers = new Thread[poolSize]; + + for (int i = 0; i < poolSize; i++) { + workers[i] = new Thread(worker); + workers[i].start(); + } + } + + /** + * Worker thread routine for ThreadPool. + */ + private Runnable worker = () -> { + LightFutureImpl future; + try { + while (!Thread.currentThread().isInterrupted()) { + synchronized (queue) { + while (queue.isEmpty()) { + queue.wait(); + } + future = queue.poll(); + } + + synchronized (future) { + future.compute(); + future.notify(); + } + } + } catch (InterruptedException e) { + } + + }; + + /** + * Adds a task to the pool, returning a LightFuture object. + * @param supplier supplier for the computation + * @param type of the result + * @return LightFuture object that will contain the result of computation + */ + @Override + public LightFuture addTask(Supplier supplier) { + LightFutureImpl future = new LightFutureImpl(supplier); + synchronized (queue) { + queue.add(future); + queue.notify(); + } + return future; + } + + /** + * Shuts down all of its current workers. + */ + @Override + public void shutdown() throws InterruptedException { + for (Thread thread: workers) { + thread.interrupt(); + } + synchronized (queue) { + while (!queue.isEmpty()) { + queue.remove().caughtException = true; + } + } + for (Thread thread : workers) { + thread.join(); + } + } + + /** + * An implementation of LightFuture interface for + * @param + */ + private class LightFutureImpl implements LightFuture { + + /** + * The LightFuture's supplier. + */ + private final Supplier supplier; + + /** + * The status of the computation. + */ + private volatile boolean isReady = false; + + private List> thenApplied = new LinkedList<>(); + + /** + * The result of the computation. + */ + private volatile T result; + + /** + * Whether an exception occurred during supplier's execution. + */ + private volatile boolean caughtException = false; + + private LightFutureImpl(@NotNull Supplier supplier) { + this.supplier = supplier; + } + + /** + * Returns whether a computation is completed. + * @return whether a computation is completed + */ + @Override + public boolean isReady() { + return isReady; + } + + /** + * Returns the result of the computation, if it is not completed, this method blocks the execution. + * @return result of the computation + * @throws LightFutureException if an exception occurred during a computation + */ + @Override + public T get() throws LightFutureException { + synchronized (this) { + while (!isReady) { + try { + wait(); + } catch (InterruptedException e) { + throw new LightFutureException(); + } + } + } + if (caughtException) { + throw new LightFutureException(); + } + return result; + } + + /** + * Computes the value and tells everybody that the value is ready. + */ + private void compute() { + try { + result = supplier.get(); + } catch (Throwable e) { + caughtException = true; + } + isReady = true; + synchronized (queue) { + queue.addAll(thenApplied); + notifyAll(); + } + } + + /** + * Applies the result of current computation to another and returns another computation's LightFuture. + * @param function the function to compute with this LightFuture's result + * @param type that the function returns + * @return the result of the function + */ + @Override + public LightFuture thenApply(Function function) { + synchronized (this) { + if (caughtException) { + throw new LightFutureException(); + } + + if (!isReady) { + LightFutureImpl future = new LightFutureImpl<>(() -> function.apply(get())); + thenApplied.add(future); + return future; + } + return addTask(()->function.apply(result)); + } + } + } +} diff --git a/ThreadPool/src/test/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolTest.java b/ThreadPool/src/test/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolTest.java new file mode 100644 index 0000000..48a1648 --- /dev/null +++ b/ThreadPool/src/test/java/ru/spbau/dkaznacheev/threadpool/ThreadPoolTest.java @@ -0,0 +1,127 @@ +package ru.spbau.dkaznacheev.threadpool; + +import org.junit.Test; + +import java.util.ArrayList; +import java.util.HashSet; +import java.util.Set; +import java.util.function.Supplier; + +import static org.junit.Assert.*; + +public class ThreadPoolTest { + @Test + public void threadPoolSimpleTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + LightFuture future = pool.addTask(() -> 4); + assertEquals(4, (int)future.get()); + assertTrue(future.isReady()); + } + + @Test + public void threadPoolManyTaskTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + for (int i = 0; i < 100; i++) { + LightFuture future = pool.addTask(() -> 4); + assertEquals(4, (int) future.get()); + } + } + + @Test + public void threadPoolSimpleLongTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + LightFuture future = pool.addTask(() -> { + try { + Thread.sleep(500); + } catch (InterruptedException e) { + } + return 4; + }); + assertFalse(future.isReady()); + assertEquals(4, (int)future.get()); + assertTrue(future.isReady()); + } + + @Test (expected = LightFutureException.class) + public void threadPoolThrowsTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + LightFuture future = pool.addTask(() -> { + throw new RuntimeException(); + }); + future.get(); + } + + @Test + public void threadPoolThrowsDoesntBreak() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + for (int i = 0; i < 10; i++) { + pool.addTask(() -> { + throw new RuntimeException(); + }); + } + LightFuture future = pool.addTask(() -> 4); + assertEquals(4, (int)future.get()); + } + + @Test + public void threadPoolShutdownTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + pool.addTask(() -> { + return true; + }); + pool.shutdown(); + } + + @Test + public void threadPoolThenApplyTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + LightFuture future1 = pool.addTask(() -> 4); + LightFuture future2 = future1.thenApply((x) -> x * 2); + assertEquals(8, (int)future2.get()); + } + + @Test + public void threadPoolThenApplyLongTest() throws Exception { + ThreadPool pool = new ThreadPoolImpl(4); + LightFuture future1 = pool.addTask(() -> { + try { + Thread.sleep(500); + } catch (InterruptedException e) { + } + return 4; + }); + LightFuture future2 = future1.thenApply((x) -> x * 2); + assertEquals(8, (int)future2.get()); + } + + + + @Test + public void threadPoolHasNThreads() throws Exception { + ThreadPool pool = new ThreadPoolImpl(5); + Set threads = new HashSet<>(); + for (int i = 0; i < 100; i++) { + pool.addTask(() -> { + synchronized (threads) { + threads.add(Thread.currentThread().getName()); + } + while (true) { + + } + }); + } + Thread.sleep(1000); + assertEquals(5, threads.size()); + } + + @Test + public void nonBlockingThenApply() throws Exception { + ThreadPool pool = new ThreadPoolImpl(5); + LightFuture future = pool.addTask(() -> { + while (true) { + + } + }); + future.thenApply((result) -> !result); + } +} \ No newline at end of file