2.17.2: 2011-06-17

Class ProcessJobExecutor

  extended by net.sf.basedb.clients.jobagent.executors.ProcessJobExecutor
All Implemented Interfaces:

public class ProcessJobExecutor
extends Object
implements JobExecutor

This is a job executor which starts a new process for each job to be executed. This has the advantage that a misbehaving job can't interfere with other jobs or the job agent. For example, a call to System.exit(int) would only result in the job's process getting killed. Other jobs and the job agent would not be affected. Another advantage is that it makes it possible to apply a security policy to the new process for plugins that are not trusted with full access to the computer. See PluginDefinition.isTrusted().

The disadvantage is the overhead in time and memory of starting a new process.

Configuration parameter Default value Description
agent.executor.process.java Path to the java executable to use. not specified the envoronment variable JAVA_HOME is used if it exists. Otherwise we let the operating system find the java command.
agent.executor.process.options -server Extra command line options to pass to the java executable: java <options> -cp ... className ....

Last modified
$Date: 2010-09-02 14:09:15 +0200 (Thu, 02 Sep 2010) $

Nested Class Summary
static class ProcessJobExecutor.StreamRedirector
          Used for redirecting standard output to a string.
Field Summary
private  String javaBin
private static Logger log
          Log job agent events.
private  String options
private  SignalHandler signalHandler
private  SignalReceiver signalReceiver
Constructor Summary
Method Summary
 void close()
          This method is called at when the agent is stopped or paused.
 void executeJob(SessionControl sc, Agent agent, Job job, JobAgentSettings settings, Job.ExecutionTime usedSlot)
          Execute the specified job.
 void init(Agent agent)
          Initialize the job executor.
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail


private static final Logger log
Log job agent events.


private String javaBin


private String options


private SignalReceiver signalReceiver


private SignalHandler signalHandler
Constructor Detail


public ProcessJobExecutor()
Method Detail


public void init(Agent agent)
Description copied from interface: JobExecutor
Initialize the job executor. This method is called once immediately after the object has been created.

Specified by:
init in interface JobExecutor
agent - The agent


public void executeJob(SessionControl sc,
                       Agent agent,
                       Job job,
                       JobAgentSettings settings,
                       Job.ExecutionTime usedSlot)
Description copied from interface: JobExecutor
Execute the specified job. This method is called in a new thread created specifically for running that job. If the agent is shutting down it will send an interrupt signal to all job threads. It is up to the job executor to decide how to handle this. It may either decide to kill the job or let it continue as if nothing happened.

The job sent to this method has it's status set to Job.Status.PREPARED. The implementation of this method must change the status to either Job.Status.DONE or Job.Status.ERROR. If the status hasn't changed the job agent will set the status to signal an unknown error.

Specified by:
executeJob in interface JobExecutor
sc - A SessionControl where the owner of the job is logged in and the correct active project is set
agent - The agent that sent the request to execute the job
job - The job to execute
settings - The specific settings used for the plugin on this job agent or null if no settings has been specified
usedSlot - The slot that was used to execut the job


public void close()
Description copied from interface: JobExecutor
This method is called at when the agent is stopped or paused. No more execution requests will be sent to the current job executor, but running jobs should NOT be terminated due to this method beeing called.

Specified by:
close in interface JobExecutor

2.17.2: 2011-06-17