Double check lock ThreadPoolManager sigleton, constrain input and output circular blocking queues to 256 elements, fix build.xml for java 8

Author: neocoretechs

src/main/java/build.xml

@@ -26,7 +26,7 @@
 
   <!-- Compiles the java code (including the usage of library for JUnit -->
   <target name="compile" depends="makedir">
-    <javac srcdir="${src.dir}" destdir="${build.dir}" classpath="${lib.dir}/commons-pool-1.6.jar:${lib.dir}/commons-lang-2.6.jar:${lib.dir}/ws-commons-util-1.0.1.jar:${lib.dir}/en_us.jar:${lib.dir}/commons-digester-1.8.1.jar:${lib.dir}/commons-logging-1.1.2.jar:${lib.dir}/commons-io-2.4.jar:${lib.dir}/RosBase.jar:${lib.dir}/commons-net-1.4.1.jar:${lib.dir}/RosMsgs.jar">
+    <javac compiler="modern" srcdir="${src.dir}" destdir="${build.dir}" classpath="${lib.dir}/commons-pool-1.6.jar:${lib.dir}/commons-lang-2.6.jar:${lib.dir}/ws-commons-util-1.0.1.jar:${lib.dir}/en_us.jar:${lib.dir}/commons-digester-1.8.1.jar:${lib.dir}/commons-logging-1.1.2.jar:${lib.dir}/commons-io-2.4.jar:${lib.dir}/RosBase.jar:${lib.dir}/commons-net-1.4.1.jar:${lib.dir}/RosMsgs.jar">
     </javac>
 
   </target>

src/main/java/org/ros/internal/node/server/ThreadPoolManager.java

@@ -13,7 +13,6 @@
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 
-
 /**
  * Class to manage thread resources throughout the application. Singleton
  * Usage pattern is ThreadPoolManager.getInstance().spin([your Runnable])
@@ -27,17 +26,21 @@
  */
 public class ThreadPoolManager {
 	private static final boolean DEBUG = false;
-	  private static final Log log = LogFactory.getLog(ThreadPoolManager.class);
+	private static final Log log = LogFactory.getLog(ThreadPoolManager.class);
 	private static String DEFAULT_THREAD_POOL = "RPCSERVER";
 	private int threadNum = 0;
     private static Map<String, ExecutorService> executor = new HashMap<String, ExecutorService>();// = Executors.newCachedThreadPool(dtf);
 
-	public static ThreadPoolManager threadPoolManager = null;
+	public static volatile ThreadPoolManager threadPoolManager = null;
 	private ThreadPoolManager() { }
 
 	public static ThreadPoolManager getInstance() {
 		if( threadPoolManager == null ) {
-			threadPoolManager = new ThreadPoolManager();
+			synchronized(ThreadPoolManager.class) {
+				if(threadPoolManager == null) {
+					threadPoolManager = new ThreadPoolManager();
+				}
+			}
 			// set up pool for system processes
 			executor.put(DEFAULT_THREAD_POOL, Executors.newCachedThreadPool(getInstance().new LocalThreadFactory(DEFAULT_THREAD_POOL)));
 		}

src/main/java/org/ros/internal/transport/queue/OutgoingMessageQueue.java

@@ -33,7 +33,7 @@ public class OutgoingMessageQueue<T> {
   private static final boolean DEBUG = false;
   private static final Log log = LogFactory.getLog(OutgoingMessageQueue.class);
 
-  private static final int DEQUE_CAPACITY = 8192;
+  private static final int DEQUE_CAPACITY = 256;
 
   private final CircularBlockingDeque<T> deque;
   private final Writer writer;