Initial commit

.idea/.gitignore

+# Default ignored files
+/shelf/
+/workspace.xml

.idea/compiler.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <annotationProcessing>
+      <profile name="Maven default annotation processors profile" enabled="true">
+        <sourceOutputDir name="target/generated-sources/annotations" />
+        <sourceTestOutputDir name="target/generated-test-sources/test-annotations" />
+        <outputRelativeToContentRoot value="true" />
+        <module name="ThreadPoolImplementaion" />
+      </profile>
+    </annotationProcessing>
+  </component>
+</project>
\ No newline at end of file

.idea/encodings.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="Encoding">
+    <file url="file://$PROJECT_DIR$/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/src/main/resources" charset="UTF-8" />
+  </component>
+</project>
\ No newline at end of file

.idea/jarRepositories.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="RemoteRepositoriesConfiguration">
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Central Repository" />
+      <option name="url" value="https://repo.maven.apache.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="central" />
+      <option name="name" value="Maven Central repository" />
+      <option name="url" value="https://repo1.maven.org/maven2" />
+    </remote-repository>
+    <remote-repository>
+      <option name="id" value="jboss.community" />
+      <option name="name" value="JBoss Community repository" />
+      <option name="url" value="https://repository.jboss.org/nexus/content/repositories/public/" />
+    </remote-repository>
+  </component>
+</project>
\ No newline at end of file

.idea/misc.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ExternalStorageConfigurationManager" enabled="true" />
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_19" default="true" project-jdk-name="19" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>
\ No newline at end of file

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.example</groupId>
+    <artifactId>ThreadPoolImplementaion</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>19</maven.compiler.source>
+        <maven.compiler.target>19</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+</project>
\ No newline at end of file

src/main/java/Main.java

+public class Main
+{
+    public static void main(String[] args) throws Exception {
+
+        ThreadPool threadPool = new ThreadPool(3, 10);
+
+        for(int i=0; i<10; i++) {
+
+            int taskNo = i;
+            threadPool.execute( () -> {
+                String message =
+                        Thread.currentThread().getName()
+                                + ": Task " + taskNo ;
+                System.out.println(message);
+            });
+        }
+
+        threadPool.Wait_Xms_UntillAllTasksFinished(1000);
+        threadPool.Stop();
+
+    }
+}

src/main/java/MyBlockingQueue.java

+import java.util.LinkedList;
+import java.util.Queue;
+
+public class MyBlockingQueue <T>
+{
+    private Queue<T> queue;
+    private int Q_Size;
+
+    public MyBlockingQueue(int q_Size)
+    {
+        queue = new LinkedList<>();
+        this.Q_Size = q_Size;
+    }
+
+    public synchronized void Enqueue(T element) throws InterruptedException
+    {
+        while(queue.size() == Q_Size)
+        {
+            wait();
+        }
+        queue.offer(element);
+        notify();
+    }
+
+    public synchronized T dequeue() throws InterruptedException
+    {
+        while(queue.isEmpty())
+        {
+            wait();
+        }
+        T element = queue.poll();
+        notify();
+        return element;
+    }
+
+    public synchronized int Size()
+    {
+        return queue.size();
+    }
+}

src/main/java/PoolThreadRunnable.java

+public class PoolThreadRunnable implements Runnable
+{
+    Thread thread = null;
+    MyBlockingQueue<Runnable> taskqueue = null;
+    boolean isStopped = false;
+
+    public PoolThreadRunnable(MyBlockingQueue queue)
+    {
+        taskqueue = queue;
+    }
+    @Override
+    public void run()
+    {
+        this.thread = Thread.currentThread();
+
+        while (!isStopped)
+        {
+            try
+            {
+                Runnable task = taskqueue.dequeue();
+                task.run();
+            }
+            catch (InterruptedException e)
+            {
+                //do nothing,,, cause task might be null
+            }
+        }
+    }
+
+    public synchronized void Stop()
+    {
+        isStopped = true;
+        this.thread.interrupt();
+    }
+
+    public synchronized boolean isStopped()
+    {
+        return isStopped;
+    }
+}

src/main/java/ThreadPool.java

+import java.util.ArrayList;
+import java.util.List;
+
+public class ThreadPool
+{
+    MyBlockingQueue<Runnable> taskqueue = null;
+    List<PoolThreadRunnable> threads = new ArrayList<PoolThreadRunnable>();
+    boolean isStopped = false;
+
+    public ThreadPool(int n_threads, int q_size)
+    {
+        this.taskqueue = new MyBlockingQueue<>(q_size);
+
+        for(int i = 0; i<n_threads; i++)
+        {
+            PoolThreadRunnable thread = new PoolThreadRunnable(taskqueue);
+            threads.add(thread);
+        }
+
+        for (PoolThreadRunnable thread: threads)
+        {
+            new Thread(thread).start();
+        }
+    }
+
+    public synchronized void execute(Runnable task) throws Exception
+    {
+        if(isStopped)
+                throw new IllegalStateException("thread is stopped");
+
+        taskqueue.Enqueue(task);
+    }
+
+    public synchronized void Stop()
+    {
+        isStopped = true;
+
+        for(PoolThreadRunnable thread: threads)
+        {
+            thread.Stop();
+        }
+    }
+
+    public synchronized void Wait_Xms_UntillAllTasksFinished(int duration_ms)
+    {
+        if(taskqueue.Size() > 0)
+        {
+            try
+            {
+                Thread.sleep(duration_ms);
+            }
+            catch (InterruptedException e)
+            {
+                System.out.println(e.getStackTrace());
+            }
+        }
+    }
+
+
+
+}