org.apache.flink.runtime.jobgraph.tasks.AbstractInvokable Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
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* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.runtime.jobgraph.tasks;
import org.apache.flink.api.common.ExecutionConfig;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.runtime.execution.Environment;
import org.apache.flink.runtime.operators.BatchTask;
/**
* This is the abstract base class for every task that can be executed by a
* TaskManager. Concrete tasks like the vertices of batch jobs (see
* {@link BatchTask} inherit from this class.
*
* The TaskManager invokes the {@link #invoke()} method when executing a
* task. All operations of the task happen in this method (setting up input
* output stream readers and writers as well as the task's core operation).
*/
public abstract class AbstractInvokable {
/** The environment assigned to this invokable. */
private Environment environment;
/**
* Starts the execution.
*
*
Must be overwritten by the concrete task implementation. This method
* is called by the task manager when the actual execution of the task
* starts.
*
*
All resources should be cleaned up when the method returns. Make sure
* to guard the code with try-finally blocks where necessary.
*
* @throws Exception
* Tasks may forward their exceptions for the TaskManager to handle through failure/recovery.
*/
public abstract void invoke() throws Exception;
/**
* This method is called when a task is canceled either as a result of a user abort or an execution failure. It can
* be overwritten to respond to shut down the user code properly.
*
* @throws Exception
* thrown if any exception occurs during the execution of the user code
*/
public void cancel() throws Exception {
// The default implementation does nothing.
}
/**
* Sets the environment of this task.
*
* @param environment
* the environment of this task
*/
public final void setEnvironment(Environment environment) {
this.environment = environment;
}
/**
* Returns the environment of this task.
*
* @return The environment of this task.
*/
public Environment getEnvironment() {
return this.environment;
}
/**
* Returns the user code class loader of this invokable.
*
* @return user code class loader of this invokable.
*/
public ClassLoader getUserCodeClassLoader() {
return getEnvironment().getUserClassLoader();
}
/**
* Returns the current number of subtasks the respective task is split into.
*
* @return the current number of subtasks the respective task is split into
*/
public int getCurrentNumberOfSubtasks() {
return this.environment.getTaskInfo().getNumberOfParallelSubtasks();
}
/**
* Returns the index of this subtask in the subtask group.
*
* @return the index of this subtask in the subtask group
*/
public int getIndexInSubtaskGroup() {
return this.environment.getTaskInfo().getIndexOfThisSubtask();
}
/**
* Returns the task configuration object which was attached to the original {@link org.apache.flink.runtime.jobgraph.JobVertex}.
*
* @return the task configuration object which was attached to the original {@link org.apache.flink.runtime.jobgraph.JobVertex}
*/
public Configuration getTaskConfiguration() {
return this.environment.getTaskConfiguration();
}
/**
* Returns the job configuration object which was attached to the original {@link org.apache.flink.runtime.jobgraph.JobGraph}.
*
* @return the job configuration object which was attached to the original {@link org.apache.flink.runtime.jobgraph.JobGraph}
*/
public Configuration getJobConfiguration() {
return this.environment.getJobConfiguration();
}
/**
* Returns the global ExecutionConfig.
*/
public ExecutionConfig getExecutionConfig() {
return this.environment.getExecutionConfig();
}
}