org.trpr.platform.batch.impl.spring.jmx.JMXJobUtils.java Source code

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Here is the source code for org.trpr.platform.batch.impl.spring.jmx.JMXJobUtils.java

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/*
 * Copyright 2012-2015, the original author or authors.
 *
 * Licensed 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,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.trpr.platform.batch.impl.spring.jmx;

import java.lang.management.ManagementFactory;
import java.util.Map;
import java.util.Set;

import javax.management.MBeanServer;
import javax.management.ObjectInstance;
import javax.management.openmbean.CompositeData;
import javax.management.openmbean.TabularDataSupport;

import org.springframework.batch.core.BatchStatus;

/**
 * The <code> JMXJobUtils </code> is a utility class for job related actions exposed via JMX by {@link JobAdministrator}
 * 
 * @author Regunath B
 * @version 1.0, 04/10/2012
 * 
 */
public class JMXJobUtils {

    /** Array of Batch completion status strings - success and failure */
    private static final String[] BATCH_COMPLETION_STATUSES = { BatchStatus.ABANDONED.name(),
            BatchStatus.COMPLETED.name(), BatchStatus.FAILED.name(), BatchStatus.STOPPED.name(), };

    /** The JobAdministrator name part of MBean object name*/
    private static final String JOB_ADMINISTRATOR = "JobAdministrator";

    /** Job method names and param names*/
    private static final String RUN_JOB = "runJob";
    private static final String JOB_METRICS = "getIndividualJobExecutionMetrics";
    private static final String JOB_PARAM_NAME = "jobName";
    private static final String JOB_PARAM_STATUS = "jobStatus";

    /** The JMX objects*/
    private MBeanServer mbeanServer = null;
    private ObjectInstance jobAdministratorInstance = null;

    /**
     * Constructor for this class
     */
    public JMXJobUtils() {
        this.mbeanServer = ManagementFactory.getPlatformMBeanServer();
        Set<ObjectInstance> mbeans = mbeanServer.queryMBeans(null, null);
        for (ObjectInstance mbean : mbeans) {
            if (mbean.getObjectName().toString().indexOf(JOB_ADMINISTRATOR) > -1) {
                this.jobAdministratorInstance = mbean;
                break;
            }
        }
    }

    /**
     * Runs the specified job.
     * @param jobName the valid job name to execute
     * @throws Exception all Runtime and Checked exceptions thrown, if any, when executing the specified job
     */
    public void runJob(String jobName) throws Exception {
        this.mbeanServer.invoke(jobAdministratorInstance.getObjectName(), RUN_JOB, new Object[] { jobName },
                new String[] { String.class.getName() });
    }

    /**
     * Polls the JobAdministrator for last execution status of the specified job. Makes the current thread sleep for the specified duration between consecutive
     * checks
     * @param jobName the job to wait for execution completion
     * @param checkFrequency the sleep time in ms between status checks
     * @throws Exception all Runtime and Checked exceptions thrown, if any, when monitoring the specified job
     * @return the exist status as String
     */
    public String waitForJobExecution(String jobName, long checkFrequency) throws Exception {
        while (true) {
            Thread.sleep(checkFrequency);
            TabularDataSupport batchStats = (TabularDataSupport) this.mbeanServer
                    .invoke(this.jobAdministratorInstance.getObjectName(), JOB_METRICS, null, null);
            Set<Map.Entry<Object, Object>> stats = batchStats.entrySet();
            for (Map.Entry entry : stats) {
                CompositeData data = (CompositeData) entry.getValue();
                if (data.get(JOB_PARAM_NAME).equals(jobName) && data.get(JOB_PARAM_STATUS) != null) {
                    String status = data.get("jobStatus").toString();
                    for (String completedStatus : BATCH_COMPLETION_STATUSES) {
                        if (status.equalsIgnoreCase(completedStatus)) {
                            // job has completed execution, so exit.
                            return status;
                        }
                    }
                }
            }
        }

    }

}