org.apache.flink.runtime.operators.util.TaskConfig Java Examples

@Test
public void testOnlyOutputFormat() {
	InputOutputFormatContainer formatContainer = new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader());

	OperatorID operatorID = new OperatorID();
	formatContainer.addOutputFormat(operatorID, new DiscardingOutputFormat<>());

	Configuration parameters = new Configuration();
	parameters.setString("parameter1", "bcd234");
	formatContainer.addParameters(operatorID, parameters);

	TaskConfig taskConfig = new TaskConfig(new Configuration());
	formatContainer.write(taskConfig);

	InputOutputFormatContainer loadedFormatContainer = new InputOutputFormatContainer(taskConfig, getClass().getClassLoader());

	Map<OperatorID, UserCodeWrapper<? extends OutputFormat<?>>> outputFormats = loadedFormatContainer.getOutputFormats();
	assertEquals(1, outputFormats.size());
	assertEquals(0, loadedFormatContainer.getInputFormats().size());

	assertTrue(outputFormats.get(operatorID).getUserCodeObject() instanceof DiscardingOutputFormat);

	Configuration loadedParameters = loadedFormatContainer.getParameters(operatorID);
	assertEquals(1, loadedParameters.keySet().size());
	assertEquals("bcd234", loadedParameters.getString("parameter1", null));
}
 

public void registerFileInputTask(
	AbstractInvokable inTask,
	Class<? extends DelimitedInputFormat<Record>> stubClass,
	String inPath,
	String delimiter)	{

	DelimitedInputFormat<Record> format;
	try {
		format = stubClass.newInstance();
	}
	catch (Throwable t) {
		throw new RuntimeException("Could not instantiate test input format.", t);
	}

	format.setFilePath(inPath);
	format.setDelimiter(delimiter);

	OperatorID operatorID = new OperatorID();
	new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader())
		.addInputFormat(operatorID, format)
		.write(new TaskConfig(this.mockEnv.getTaskConfiguration()));

	this.inputSplitProvider.addInputSplits(inPath, 5);
}
 

private JobVertex createDataSinkVertex(SinkPlanNode node) throws CompilerException {
	final InputOutputFormatVertex vertex = new InputOutputFormatVertex(node.getNodeName());
	final TaskConfig config = new TaskConfig(vertex.getConfiguration());

	final OperatorID operatorID = new OperatorID();

	vertex.setResources(node.getMinResources(), node.getPreferredResources());
	vertex.setInvokableClass(DataSinkTask.class);
	vertex.setFormatDescription(operatorID, getDescriptionForUserCode(node.getProgramOperator().getUserCodeWrapper()));

	// set user code
	new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader())
		.addOutputFormat(operatorID, (UserCodeWrapper<? extends OutputFormat<?>>) node.getProgramOperator().getUserCodeWrapper())
		.addParameters(operatorID, node.getProgramOperator().getParameters())
		.write(config);

	return vertex;
}
 

@Override
protected void initOutputs() throws Exception {
	// initialize the regular outputs first (the ones into the step function).
	super.initOutputs();

	// at this time, the outputs to the step function are created
	// add the outputs for the final solution
	List<RecordWriter<?>> finalOutputWriters = new ArrayList<RecordWriter<?>>();
	final TaskConfig finalOutConfig = this.config.getIterationHeadFinalOutputConfig();
	final ClassLoader userCodeClassLoader = getUserCodeClassLoader();
	this.finalOutputCollector = BatchTask.getOutputCollector(this, finalOutConfig,
			userCodeClassLoader, finalOutputWriters, config.getNumOutputs(), finalOutConfig.getNumOutputs());

	// sanity check the setup
	final int writersIntoStepFunction = this.eventualOutputs.size();
	final int writersIntoFinalResult = finalOutputWriters.size();
	final int syncGateIndex = this.config.getIterationHeadIndexOfSyncOutput();

	if (writersIntoStepFunction + writersIntoFinalResult != syncGateIndex) {
		throw new Exception("Error: Inconsistent head task setup - wrong mapping of output gates.");
	}
	// now, we can instantiate the sync gate
	this.toSync = new RecordWriter<IOReadableWritable>(getEnvironment().getWriter(syncGateIndex));
	this.toSyncPartitionId = getEnvironment().getWriter(syncGateIndex).getPartitionId();
}
 

@Test
public void testOnlyInputFormat() {
	InputOutputFormatContainer formatContainer = new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader());

	OperatorID operatorID = new OperatorID();
	formatContainer.addInputFormat(operatorID, new TestInputFormat("test input format"));
	formatContainer.addParameters(operatorID, "parameter1", "abc123");

	TaskConfig taskConfig = new TaskConfig(new Configuration());
	formatContainer.write(taskConfig);

	InputOutputFormatContainer loadedFormatContainer = new InputOutputFormatContainer(taskConfig, getClass().getClassLoader());

	Map<OperatorID, UserCodeWrapper<? extends InputFormat<?, ?>>> inputFormats = loadedFormatContainer.getInputFormats();
	assertEquals(1, inputFormats.size());
	assertEquals(0, loadedFormatContainer.getOutputFormats().size());

	TestInputFormat inputFormat = (TestInputFormat) inputFormats.get(operatorID).getUserCodeObject();
	assertEquals("test input format", inputFormat.getName());

	Configuration parameters = loadedFormatContainer.getParameters(operatorID);
	assertEquals(1, parameters.keySet().size());
	assertEquals("abc123", parameters.getString("parameter1", null));
}
 

public void registerFileInputTask(
	AbstractInvokable inTask,
	Class<? extends DelimitedInputFormat<Record>> stubClass,
	String inPath,
	String delimiter)	{

	DelimitedInputFormat<Record> format;
	try {
		format = stubClass.newInstance();
	}
	catch (Throwable t) {
		throw new RuntimeException("Could not instantiate test input format.", t);
	}

	format.setFilePath(inPath);
	format.setDelimiter(delimiter);

	OperatorID operatorID = new OperatorID();
	new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader())
		.addInputFormat(operatorID, format)
		.write(new TaskConfig(this.mockEnv.getTaskConfiguration()));

	this.inputSplitProvider.addInputSplits(inPath, 5);
}
 

@Override
public void prepare() throws Exception {
	final TaskConfig config = this.taskContext.getTaskConfig();
	if (config.getDriverStrategy() != DriverStrategy.CO_GROUP_RAW) {
		throw new Exception("Unrecognized driver strategy for CoGoup Python driver: " + config.getDriverStrategy().name());
	}

	final MutableObjectIterator<IT1> in1 = this.taskContext.getInput(0);
	final MutableObjectIterator<IT2> in2 = this.taskContext.getInput(1);

	IT1 reuse1 = this.taskContext.<IT1>getInputSerializer(0).getSerializer().createInstance();
	IT2 reuse2 = this.taskContext.<IT2>getInputSerializer(1).getSerializer().createInstance();

	this.coGroupIterator1 = new SimpleIterable<IT1>(reuse1, in1);
	this.coGroupIterator2 = new SimpleIterable<IT2>(reuse2, in2);

	if (LOG.isDebugEnabled()) {
		LOG.debug(this.taskContext.formatLogString("CoGroup task iterator ready."));
	}
}
 

@Override
public void prepare() throws Exception {
	TaskConfig config = this.taskContext.getTaskConfig();
	if (config.getDriverStrategy() != DriverStrategy.SORTED_REDUCE) {
		throw new Exception("Unrecognized driver strategy for Reduce driver: " + config.getDriverStrategy().name());
	}
	this.serializer = this.taskContext.<T>getInputSerializer(0).getSerializer();
	this.comparator = this.taskContext.getDriverComparator(0);
	this.input = this.taskContext.getInput(0);

	ExecutionConfig executionConfig = taskContext.getExecutionConfig();
	this.objectReuseEnabled = executionConfig.isObjectReuseEnabled();

	if (LOG.isDebugEnabled()) {
		LOG.debug("ReduceDriver object reuse: " + (this.objectReuseEnabled ? "ENABLED" : "DISABLED") + ".");
	}
}
 

protected DriverTestBase(ExecutionConfig executionConfig, long memory, int maxNumSorters, long perSortMemory) {
	if (memory < 0 || maxNumSorters < 0 || perSortMemory < 0) {
		throw new IllegalArgumentException();
	}
	
	final long totalMem = Math.max(memory, 0) + (Math.max(maxNumSorters, 0) * perSortMemory);
	
	this.perSortMem = perSortMemory;
	this.perSortFractionMem = (double)perSortMemory/totalMem;
	this.ioManager = new IOManagerAsync();
	this.memManager = totalMem > 0 ? new MemoryManager(totalMem,1) : null;

	this.inputs = new ArrayList<MutableObjectIterator<Record>>();
	this.comparators = new ArrayList<TypeComparator<Record>>();
	this.sorters = new ArrayList<UnilateralSortMerger<Record>>();
	
	this.owner = new DummyInvokable();
	this.taskConfig = new TaskConfig(new Configuration());
	this.executionConfig = executionConfig;
	this.taskManageInfo = new TestingTaskManagerRuntimeInfo();
}
 

@Override
public void prepare() throws Exception {
	final TaskConfig config = this.taskContext.getTaskConfig();
	if (config.getDriverStrategy() != DriverStrategy.ALL_REDUCE) {
		throw new Exception("Unrecognized driver strategy for AllReduce driver: " + config.getDriverStrategy().name());
	}
	
	TypeSerializerFactory<T> serializerFactory = this.taskContext.getInputSerializer(0);
	this.serializer = serializerFactory.getSerializer();
	this.input = this.taskContext.getInput(0);

	ExecutionConfig executionConfig = taskContext.getExecutionConfig();
	this.objectReuseEnabled = executionConfig.isObjectReuseEnabled();

	if (LOG.isDebugEnabled()) {
		LOG.debug("AllReduceDriver object reuse: " + (this.objectReuseEnabled ? "ENABLED" : "DISABLED") + ".");
	}
}
 

@Override
protected void initOutputs() throws Exception {
	// initialize the regular outputs first (the ones into the step function).
	super.initOutputs();

	// at this time, the outputs to the step function are created
	// add the outputs for the final solution
	List<RecordWriter<?>> finalOutputWriters = new ArrayList<RecordWriter<?>>();
	final TaskConfig finalOutConfig = this.config.getIterationHeadFinalOutputConfig();
	final ClassLoader userCodeClassLoader = getUserCodeClassLoader();
	this.finalOutputCollector = BatchTask.getOutputCollector(this, finalOutConfig,
			userCodeClassLoader, finalOutputWriters, config.getNumOutputs(), finalOutConfig.getNumOutputs());

	// sanity check the setup
	final int writersIntoStepFunction = this.eventualOutputs.size();
	final int writersIntoFinalResult = finalOutputWriters.size();
	final int syncGateIndex = this.config.getIterationHeadIndexOfSyncOutput();

	if (writersIntoStepFunction + writersIntoFinalResult != syncGateIndex) {
		throw new Exception("Error: Inconsistent head task setup - wrong mapping of output gates.");
	}
	// now, we can instantiate the sync gate
	this.toSync = new RecordWriterBuilder<>().build(getEnvironment().getWriter(syncGateIndex));
	this.toSyncPartitionId = getEnvironment().getWriter(syncGateIndex).getPartitionId();
}
 

@Test
public void testOnlyInputFormat() {
	InputOutputFormatContainer formatContainer = new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader());

	OperatorID operatorID = new OperatorID();
	formatContainer.addInputFormat(operatorID, new TestInputFormat("test input format"));
	formatContainer.addParameters(operatorID, "parameter1", "abc123");

	TaskConfig taskConfig = new TaskConfig(new Configuration());
	formatContainer.write(taskConfig);

	InputOutputFormatContainer loadedFormatContainer = new InputOutputFormatContainer(taskConfig, getClass().getClassLoader());

	Map<OperatorID, UserCodeWrapper<? extends InputFormat<?, ?>>> inputFormats = loadedFormatContainer.getInputFormats();
	assertEquals(1, inputFormats.size());
	assertEquals(0, loadedFormatContainer.getOutputFormats().size());

	TestInputFormat inputFormat = (TestInputFormat) inputFormats.get(operatorID).getUserCodeObject();
	assertEquals("test input format", inputFormat.getName());

	Configuration parameters = loadedFormatContainer.getParameters(operatorID);
	assertEquals(1, parameters.keySet().size());
	assertEquals("abc123", parameters.getString("parameter1", null));
}
 

protected BinaryOperatorTestBase(ExecutionConfig executionConfig, long memory, int maxNumSorters, long perSortMemory) {
	if (memory < 0 || maxNumSorters < 0 || perSortMemory < 0) {
		throw new IllegalArgumentException();
	}
	
	final long totalMem = Math.max(memory, 0) + (Math.max(maxNumSorters, 0) * perSortMemory);
	
	this.perSortMem = perSortMemory;
	this.perSortFractionMem = (double) perSortMemory / totalMem;
	this.ioManager = new IOManagerAsync();
	this.memManager = totalMem > 0 ? new MemoryManager(totalMem, 1) : null;
	
	this.inputs = new ArrayList<>();
	this.comparators = new ArrayList<>();
	this.sorters = new ArrayList<>();
	
	this.owner = new DummyInvokable();
	this.taskConfig = new TaskConfig(new Configuration());
	this.executionConfig = executionConfig;
	this.taskManageInfo = new TestingTaskManagerRuntimeInfo();
}
 

private JobVertex createDataSourceVertex(SourcePlanNode node) throws CompilerException {
	final InputOutputFormatVertex vertex = new InputOutputFormatVertex(node.getNodeName());
	final TaskConfig config = new TaskConfig(vertex.getConfiguration());

	final OperatorID operatorID = new OperatorID();

	vertex.setResources(node.getMinResources(), node.getPreferredResources());
	vertex.setInvokableClass(DataSourceTask.class);
	vertex.setFormatDescription(operatorID, getDescriptionForUserCode(node.getProgramOperator().getUserCodeWrapper()));

	// set user code
	new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader())
		.addInputFormat(operatorID, (UserCodeWrapper<? extends InputFormat<?, ?>>) node.getProgramOperator().getUserCodeWrapper())
		.addParameters(operatorID, node.getProgramOperator().getParameters())
		.write(config);

	config.setOutputSerializer(node.getSerializer());
	return vertex;
}
 

@Override
public void prepare() throws Exception {
	final TaskConfig config = this.taskContext.getTaskConfig();
	if (config.getDriverStrategy() != DriverStrategy.ALL_REDUCE) {
		throw new Exception("Unrecognized driver strategy for AllReduce driver: " + config.getDriverStrategy().name());
	}
	
	TypeSerializerFactory<T> serializerFactory = this.taskContext.getInputSerializer(0);
	this.serializer = serializerFactory.getSerializer();
	this.input = this.taskContext.getInput(0);

	ExecutionConfig executionConfig = taskContext.getExecutionConfig();
	this.objectReuseEnabled = executionConfig.isObjectReuseEnabled();

	if (LOG.isDebugEnabled()) {
		LOG.debug("AllReduceDriver object reuse: " + (this.objectReuseEnabled ? "ENABLED" : "DISABLED") + ".");
	}
}
 

@Test
public void testOnlyOutputFormat() {
	InputOutputFormatContainer formatContainer = new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader());

	OperatorID operatorID = new OperatorID();
	formatContainer.addOutputFormat(operatorID, new DiscardingOutputFormat<>());

	Configuration parameters = new Configuration();
	parameters.setString("parameter1", "bcd234");
	formatContainer.addParameters(operatorID, parameters);

	TaskConfig taskConfig = new TaskConfig(new Configuration());
	formatContainer.write(taskConfig);

	InputOutputFormatContainer loadedFormatContainer = new InputOutputFormatContainer(taskConfig, getClass().getClassLoader());

	Map<OperatorID, UserCodeWrapper<? extends OutputFormat<?>>> outputFormats = loadedFormatContainer.getOutputFormats();
	assertEquals(1, outputFormats.size());
	assertEquals(0, loadedFormatContainer.getInputFormats().size());

	assertTrue(outputFormats.get(operatorID).getUserCodeObject() instanceof DiscardingOutputFormat);

	Configuration loadedParameters = loadedFormatContainer.getParameters(operatorID);
	assertEquals(1, loadedParameters.keySet().size());
	assertEquals("bcd234", loadedParameters.getString("parameter1", null));
}
 

/**
 * Instantiates a user code class from is definition in the task configuration.
 * The class is instantiated without arguments using the null-ary constructor. Instantiation
 * will fail if this constructor does not exist or is not public.
 * 
 * @param <T> The generic type of the user code class.
 * @param config The task configuration containing the class description.
 * @param cl The class loader to be used to load the class.
 * @param superClass The super class that the user code class extends or implements, for type checking.
 * 
 * @return An instance of the user code class.
 */
public static <T> T instantiateUserCode(TaskConfig config, ClassLoader cl, Class<? super T> superClass) {
	try {
		T stub = config.<T>getStubWrapper(cl).getUserCodeObject(superClass, cl);
		// check if the class is a subclass, if the check is required
		if (superClass != null && !superClass.isAssignableFrom(stub.getClass())) {
			throw new RuntimeException("The class '" + stub.getClass().getName() + "' is not a subclass of '" + 
					superClass.getName() + "' as is required.");
		}
		return stub;
	}
	catch (ClassCastException ccex) {
		throw new RuntimeException("The UDF class is not a proper subclass of " + superClass.getName(), ccex);
	}
}
 

private void assignLocalStrategyResources(Channel c, TaskConfig config, int inputNum) {
	if (c.getRelativeMemoryLocalStrategy() > 0) {
		config.setRelativeMemoryInput(inputNum, c.getRelativeMemoryLocalStrategy());
		config.setFilehandlesInput(inputNum, this.defaultMaxFan);
		config.setSpillingThresholdInput(inputNum, this.defaultSortSpillingThreshold);
		config.setUseLargeRecordHandler(this.useLargeRecordHandler);
	}
}
 

@Test
public void testInputFormat() {
	try {
		final InputOutputFormatVertex vertex = new InputOutputFormatVertex("Name");

		OperatorID operatorID = new OperatorID();
		Configuration parameters = new Configuration();
		parameters.setString("test_key", "test_value");
		new InputOutputFormatContainer(Thread.currentThread().getContextClassLoader())
			.addInputFormat(operatorID, new TestInputFormat(parameters))
			.addParameters(operatorID, "test_key", "test_value")
			.write(new TaskConfig(vertex.getConfiguration()));

		final ClassLoader cl = new TestClassLoader();

		vertex.initializeOnMaster(cl);
		InputSplit[] splits = vertex.getInputSplitSource().createInputSplits(77);

		assertNotNull(splits);
		assertEquals(1, splits.length);
		assertEquals(TestSplit.class, splits[0].getClass());
	}
	catch (Exception e) {
		e.printStackTrace();
		fail(e.getMessage());
	}
}
 

public void registerTask(
		@SuppressWarnings("rawtypes") Class<? extends Driver> driver,
		Class<? extends RichFunction> stubClass) {

	final TaskConfig config = new TaskConfig(this.mockEnv.getTaskConfiguration());
	config.setDriver(driver);
	config.setStubWrapper(new UserCodeClassWrapper<>(stubClass));
}
 

private JobVertex createDualInputVertex(DualInputPlanNode node) throws CompilerException {
	final String taskName = node.getNodeName();
	final DriverStrategy ds = node.getDriverStrategy();
	final JobVertex vertex = new JobVertex(taskName);
	final TaskConfig config = new TaskConfig(vertex.getConfiguration());
	vertex.setResources(node.getMinResources(), node.getPreferredResources());
	vertex.setInvokableClass( (this.currentIteration != null && node.isOnDynamicPath()) ? IterationIntermediateTask.class : BatchTask.class);
	
	// set user code
	config.setStubWrapper(node.getProgramOperator().getUserCodeWrapper());
	config.setStubParameters(node.getProgramOperator().getParameters());
	
	// set the driver strategy
	config.setDriver(ds.getDriverClass());
	config.setDriverStrategy(ds);
	if (node.getComparator1() != null) {
		config.setDriverComparator(node.getComparator1(), 0);
	}
	if (node.getComparator2() != null) {
		config.setDriverComparator(node.getComparator2(), 1);
	}
	if (node.getPairComparator() != null) {
		config.setDriverPairComparator(node.getPairComparator());
	}
	
	// assign memory, file-handles, etc.
	assignDriverResources(node, config);
	return vertex;
}
 

private void assignDriverResources(PlanNode node, TaskConfig config) {
	final double relativeMem = node.getRelativeMemoryPerSubTask();
	if (relativeMem > 0) {
		config.setRelativeMemoryDriver(relativeMem);
		config.setFilehandlesDriver(this.defaultMaxFan);
		config.setSpillingThresholdDriver(this.defaultSortSpillingThreshold);
	}
}
 

private void assignLocalStrategyResources(Channel c, TaskConfig config, int inputNum) {
	if (c.getRelativeMemoryLocalStrategy() > 0) {
		config.setRelativeMemoryInput(inputNum, c.getRelativeMemoryLocalStrategy());
		config.setFilehandlesInput(inputNum, this.defaultMaxFan);
		config.setSpillingThresholdInput(inputNum, this.defaultSortSpillingThreshold);
		config.setUseLargeRecordHandler(this.useLargeRecordHandler);
	}
}
 

private InputOutputFormatContainer initInputOutputformatContainer(ClassLoader classLoader) throws Exception {
	try {
		return new InputOutputFormatContainer(new TaskConfig(getConfiguration()), classLoader);
	} catch (Throwable t) {
		throw new Exception("Loading the input/output formats failed: "
			+ String.join(",", formatDescriptions.values()), t);
	}
}
 

public void registerTask(
		@SuppressWarnings("rawtypes") Class<? extends Driver> driver,
		Class<? extends RichFunction> stubClass) {

	final TaskConfig config = new TaskConfig(this.mockEnv.getTaskConfiguration());
	config.setDriver(driver);
	config.setStubWrapper(new UserCodeClassWrapper<>(stubClass));
}
 

public void setHeadTask(JobVertex headTask, TaskConfig headConfig) {
	this.headTask = headTask;
	this.headFinalResultConfig = new TaskConfig(new Configuration());
	
	// check if we already had a configuration, for example if the solution set was 
	if (this.headConfig != null) {
		headConfig.getConfiguration().addAll(this.headConfig.getConfiguration());
	}
	
	this.headConfig = headConfig;
}
 

public void registerFileOutputTask(FileOutputFormat<Record> outputFormat, String outPath) {
	TaskConfig dsConfig = new TaskConfig(this.mockEnv.getTaskConfiguration());

	outputFormat.setOutputFilePath(new Path(outPath));
	outputFormat.setWriteMode(WriteMode.OVERWRITE);

	dsConfig.setStubWrapper(new UserCodeObjectWrapper<>(outputFormat));
}
 

public void registerTask(
		@SuppressWarnings("rawtypes") Class<? extends Driver> driver,
		Class<? extends RichFunction> stubClass) {

	final TaskConfig config = new TaskConfig(this.mockEnv.getTaskConfiguration());
	config.setDriver(driver);
	config.setStubWrapper(new UserCodeClassWrapper<>(stubClass));
}
 

/**
 * Initializes the OutputFormat implementation and configuration.
 * 
 * @throws RuntimeException
 *         Throws if instance of OutputFormat implementation can not be
 *         obtained.
 */
private void initOutputFormat() {
	ClassLoader userCodeClassLoader = getUserCodeClassLoader();
	// obtain task configuration (including stub parameters)
	Configuration taskConf = getTaskConfiguration();
	this.config = new TaskConfig(taskConf);

	final Pair<OperatorID, OutputFormat<IT>> operatorIDAndOutputFormat;
	InputOutputFormatContainer formatContainer = new InputOutputFormatContainer(config, userCodeClassLoader);
	try {
		operatorIDAndOutputFormat = formatContainer.getUniqueOutputFormat();
		this.format = operatorIDAndOutputFormat.getValue();

		// check if the class is a subclass, if the check is required
		if (!OutputFormat.class.isAssignableFrom(this.format.getClass())) {
			throw new RuntimeException("The class '" + this.format.getClass().getName() + "' is not a subclass of '" + 
					OutputFormat.class.getName() + "' as is required.");
		}
	}
	catch (ClassCastException ccex) {
		throw new RuntimeException("The stub class is not a proper subclass of " + OutputFormat.class.getName(), ccex);
	}

	Thread thread = Thread.currentThread();
	ClassLoader original = thread.getContextClassLoader();
	// configure the stub. catch exceptions here extra, to report them as originating from the user code 
	try {
		thread.setContextClassLoader(userCodeClassLoader);
		this.format.configure(formatContainer.getParameters(operatorIDAndOutputFormat.getKey()));
	}
	catch (Throwable t) {
		throw new RuntimeException("The user defined 'configure()' method in the Output Format caused an error: " 
			+ t.getMessage(), t);
	}
	finally {
		thread.setContextClassLoader(original);
	}
}
 

private JobVertex createDualInputVertex(DualInputPlanNode node) throws CompilerException {
	final String taskName = node.getNodeName();
	final DriverStrategy ds = node.getDriverStrategy();
	final JobVertex vertex = new JobVertex(taskName);
	final TaskConfig config = new TaskConfig(vertex.getConfiguration());
	vertex.setResources(node.getMinResources(), node.getPreferredResources());
	vertex.setInvokableClass( (this.currentIteration != null && node.isOnDynamicPath()) ? IterationIntermediateTask.class : BatchTask.class);
	
	// set user code
	config.setStubWrapper(node.getProgramOperator().getUserCodeWrapper());
	config.setStubParameters(node.getProgramOperator().getParameters());
	
	// set the driver strategy
	config.setDriver(ds.getDriverClass());
	config.setDriverStrategy(ds);
	if (node.getComparator1() != null) {
		config.setDriverComparator(node.getComparator1(), 0);
	}
	if (node.getComparator2() != null) {
		config.setDriverComparator(node.getComparator2(), 1);
	}
	if (node.getPairComparator() != null) {
		config.setDriverPairComparator(node.getPairComparator());
	}
	
	// assign memory, file-handles, etc.
	assignDriverResources(node, config);
	return vertex;
}