Merge pull request #32 from itatdcer/feature/onstart-task-event

Added the onStart event for tasks

Author: mnadeem

src/main/java/com/github/dexecutor/core/DefaultExecutionEngine.java

@@ -129,6 +129,7 @@ public ExecutionResult<T, R> call() throws Exception {
 				ExecutionResult<T, R> result = null;
 				try {
 					task.markStart();
+                                        executionListener.onStart(task);
 					r = task.execute();
 					result = ExecutionResult.success(task.getId(), r);
 					state.removeErrored(result);

src/main/java/com/github/dexecutor/core/ExecutionListener.java

@@ -22,4 +22,10 @@ public interface ExecutionListener<T, R> {
 	 * @param exception the exception caught
 	 */
 	void onError(Task<T, R> task, Exception exception);
+        /**
+	 * Called on start node execution
+	 * 
+	 * @param task the starting one
+	 */
+	void onStart(Task<T, R> task);
 }

src/main/java/com/github/dexecutor/core/QuiteExecutionListener.java

@@ -14,4 +14,9 @@ public void onError(Task<T, R> task, Exception exception) {
 
 	}
 
+    @Override
+    public void onStart(Task<T, R> task) {
+
+    }
+
 }

src/test/java/com/github/dexecutor/core/DexecutorListenerTest.java

@@ -63,6 +63,11 @@ public void onSuccess(Task<Integer, Integer> task) {
 				public void onError(Task<Integer, Integer> task, Exception exception) {
 					logger.info("onError : {}", task);			
 				}
+                                
+                                @Override
+				public void onStart(Task<Integer, Integer> task) {
+					logger.info("onStart : {}", task);			
+				}
 			});
 
 			DefaultDexecutor<Integer, Integer> executor = new DefaultDexecutor<Integer, Integer>(config);