public void determineExecutionPlan() {
List<TaskInfo> nodeQueue =
CollectionUtils.collect(
new ArrayList<Task>(entryTasks),
new Transformer<TaskInfo, Task>() {
public TaskInfo transform(Task original) {
return graph.getNode(original);
}
});
Set<TaskInfo> visitingNodes = new HashSet<TaskInfo>();
while (!nodeQueue.isEmpty()) {
TaskInfo taskNode = nodeQueue.get(0);
boolean filtered = !filter.isSatisfiedBy(taskNode.getTask());
if (filtered) {
taskNode.setRequired(false);
}
if (!taskNode.getRequired() || executionPlan.containsKey(taskNode.getTask())) {
nodeQueue.remove(0);
continue;
}
if (visitingNodes.add(taskNode)) {
// Have not seen this task before - add its dependencies to the head of the queue and leave
// this
// task in the queue
ArrayList<TaskInfo> dependsOnTasks = new ArrayList<TaskInfo>();
addAllReversed(dependsOnTasks, taskNode.getHardSuccessors());
addAllReversed(dependsOnTasks, taskNode.getSoftSuccessors());
for (TaskInfo dependsOnTask : dependsOnTasks) {
if (visitingNodes.contains(dependsOnTask)) {
throw new CircularReferenceException(
String.format(
"Circular dependency between tasks. Cycle includes [%s, %s].",
taskNode.getTask(), dependsOnTask.getTask()));
}
nodeQueue.add(0, dependsOnTask);
}
} else {
// Have visited this task's dependencies - add it to the end of the plan
nodeQueue.remove(0);
visitingNodes.remove(taskNode);
executionPlan.put(taskNode.getTask(), taskNode);
}
}
}
public TaskInfo getTaskToExecute() {
lock.lock();
try {
while (true) {
TaskInfo nextMatching = null;
boolean allTasksComplete = true;
for (TaskInfo taskInfo : executionPlan.values()) {
allTasksComplete = allTasksComplete && taskInfo.isComplete();
if (taskInfo.isReady()
&& taskInfo.allDependenciesComplete()
&& !runningProjects.contains(taskInfo.getTask().getProject().getPath())) {
nextMatching = taskInfo;
break;
}
}
if (allTasksComplete) {
return null;
}
if (nextMatching == null) {
try {
condition.await();
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
} else {
if (nextMatching.allDependenciesSuccessful()) {
nextMatching.startExecution();
runningProjects.add(nextMatching.getTask().getProject().getPath());
return nextMatching;
} else {
nextMatching.skipExecution();
condition.signalAll();
}
}
}
} finally {
lock.unlock();
}
}
public void taskComplete(TaskInfo taskInfo) {
lock.lock();
try {
if (taskInfo.isFailed()) {
handleFailure(taskInfo);
}
taskInfo.finishExecution();
runningProjects.remove(taskInfo.getTask().getProject().getPath());
condition.signalAll();
} finally {
lock.unlock();
}
}
private void handleFailure(TaskInfo taskInfo) {
Throwable executionFailure = taskInfo.getExecutionFailure();
if (executionFailure != null) {
// Always abort execution for an execution failure (as opposed to a task failure)
abortExecution();
this.failures.add(executionFailure);
return;
}
// Task failure
try {
failureHandler.onTaskFailure(taskInfo.getTask());
this.failures.add(taskInfo.getTaskFailure());
} catch (Exception e) {
// If the failure handler rethrows exception, then execution of other tasks is aborted.
// (--continue will collect failures)
abortExecution();
this.failures.add(e);
}
}