Use ThreadGroups to link tasks to any threads they create

Make sure parallel creates a separate thread group for each
thread it spawns

PR:	7980


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@274035 13f79535-47bb-0310-9956-ffa450edef68

src/main/org/apache/tools/ant/Project.java

@@ -205,6 +205,9 @@ public class Project {
     /** Records the latest task to be executed on a thread (Thread to Task). */
     private Hashtable threadTasks = new Hashtable();
 
+    /** Records the latest task to be executed on a thread Group. */
+    private Hashtable threadGroupTasks = new Hashtable();
+
     /**
      * Called to handle any input requests.
      */
@@ -1271,7 +1274,7 @@ public class Project {
      *        or information (<code>false</code>).
      */
     public void demuxOutput(String line, boolean isError) {
-        Task task = (Task) threadTasks.get(Thread.currentThread());
+        Task task = getThreadTask(Thread.currentThread());
         if (task == null) {
             fireMessageLogged(this, line, isError ? MSG_ERR : MSG_INFO);
         } else {
@@ -1319,7 +1322,7 @@ public class Project {
      */     
     public int demuxInput(byte[] buffer, int offset, int length) 
         throws IOException {
-        Task task = (Task) threadTasks.get(Thread.currentThread());
+        Task task = getThreadTask(Thread.currentThread());
         if (task == null) {
             return defaultInput(buffer, offset, length);
         } else {
@@ -1339,7 +1342,7 @@ public class Project {
      *        or information (<code>false</code>).
      */
     public void demuxFlush(String line, boolean isError) {
-        Task task = (Task) threadTasks.get(Thread.currentThread());
+        Task task = getThreadTask(Thread.currentThread());
         if (task == null) {
             fireMessageLogged(this, line, isError ? MSG_ERR : MSG_INFO);
         } else {
@@ -2113,8 +2116,10 @@ public class Project {
     public synchronized void registerThreadTask(Thread thread, Task task) {
         if (task != null) {
             threadTasks.put(thread, task);
+            threadGroupTasks.put(thread.getThreadGroup(), task);
         } else {
             threadTasks.remove(thread);
+            threadGroupTasks.remove(thread.getThreadGroup());
         }
     }
 
@@ -2126,10 +2131,18 @@ public class Project {
      *         null if no task is registered.
      */
     public Task getThreadTask(Thread thread) {
-        return (Task) threadTasks.get(thread);
+        Task task = (Task) threadTasks.get(thread);
+        if (task == null) {
+            ThreadGroup group = thread.getThreadGroup();
+            while (task == null && group != null) {
+                task = (Task) threadGroupTasks.get(group);
+                group = group.getParent();
+            }
+        }
+        return task;
     }
 
-
+    
     // Should move to a separate public class - and have API to add
     // listeners, etc.
     private static class AntRefTable extends Hashtable {

src/main/org/apache/tools/ant/taskdefs/Parallel.java

@@ -94,12 +94,17 @@ public class Parallel extends Task
      * execute the wait status.
      */
     public void execute() throws BuildException {
-        TaskThread[] threads = new TaskThread[nestedTasks.size()];
+        int numTasks = nestedTasks.size();
+        Thread[] threads = new Thread[numTasks];
+        TaskThread[] taskThreads = new TaskThread[numTasks];
         int threadNumber = 0;
         for (Enumeration e = nestedTasks.elements(); e.hasMoreElements(); 
              threadNumber++) {
             Task nestedTask = (Task) e.nextElement();
-            threads[threadNumber] = new TaskThread(threadNumber, nestedTask);
+            ThreadGroup group = new ThreadGroup("parallel");
+            TaskThread taskThread = new TaskThread(threadNumber, nestedTask);
+            taskThreads[threadNumber] = taskThread;
+            threads[threadNumber] = new Thread(group, taskThread);
         }
 
         // now start all threads        
@@ -122,7 +127,7 @@ public class Parallel extends Task
         Throwable firstException = null;
         Location firstLocation = Location.UNKNOWN_LOCATION;;
         for (int i = 0; i < threads.length; ++i) {
-            Throwable t = threads[i].getException();
+            Throwable t = taskThreads[i].getException();
             if (t != null) {
                 numExceptions++;
                 if (firstException == null) {
@@ -152,7 +157,7 @@ public class Parallel extends Task
     /**
      * thread that execs a task
      */
-    class TaskThread extends Thread {
+    private static class TaskThread implements Runnable {
         private Throwable exception;
         private Task task;
         private int taskNumber;