GenericResultWaiter.java

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 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * 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, 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.apache.ofbiz.service;

import java.util.Map;

import org.apache.ofbiz.base.util.Debug;

/**
 * Generic Result Waiter Class
 */
@SuppressWarnings("serial")
public class GenericResultWaiter implements GenericRequester {

    public static final String module = GenericResultWaiter.class.getName();

    /** Status code for a running service */
    public static final int SERVICE_RUNNING = -1;
    /** Status code for a failed service */
    public static final int SERVICE_FAILED = 0;
    /** Status code for a successful service */
    public static final int SERVICE_FINISHED = 1;

    private boolean completed = false;
    private int status = -1;
    private Map<String, Object> result = null;
    private Throwable t = null;

    /**
     * @see org.apache.ofbiz.service.GenericRequester#receiveResult(java.util.Map)
     */
    public synchronized void receiveResult(Map<String, Object> result) {
        this.result = result;
        completed = true;
        status = SERVICE_FINISHED;
        notify();
        if (Debug.verboseOn())
            Debug.logVerbose("Received Result (" + completed + ") -- " + result, module);
    }

    /**
     * @see org.apache.ofbiz.service.GenericRequester#receiveThrowable(java.lang.Throwable)
     */
    public synchronized void receiveThrowable(Throwable t) {
        this.t = t;
        completed = true;
        status = SERVICE_FAILED;
        notify();
    }

    /**
     * Returns the status of the service.
     * @return int Status code
     */
    public synchronized int status() {
        return this.status;
    }

    /**
     * If the service has completed return true
     * @return boolean
     */
    public synchronized boolean isCompleted() {
        return completed;
    }

    /**
     * Returns the exception which was thrown or null if none
     * @return Exception
     */
    public synchronized Throwable getThrowable() {
        if (!isCompleted())
            throw new java.lang.IllegalStateException("Cannot return exception, synchronous call has not completed.");
        return this.t;
    }

    /**
     * Gets the results of the service or null if none
     * @return Map
     */
    public synchronized Map<String, Object> getResult() {
        if (!isCompleted())
            throw new java.lang.IllegalStateException("Cannot return result, asynchronous call has not completed.");
        return result;
    }

    /**
     * Waits for the service to complete
     * @return Map
     */
    public synchronized Map<String, Object> waitForResult() {
        return this.waitForResult(10);
    }

    /**
     * Waits for the service to complete, check the status ever n milliseconds
     * @param milliseconds
     * @return Map
     */
    public synchronized Map<String, Object> waitForResult(long milliseconds) {
        if (Debug.verboseOn()) Debug.logVerbose("Waiting for results...", module);
        while (!isCompleted()) {
            try {
                this.wait(milliseconds);
                if (Debug.verboseOn()) Debug.logVerbose("Waiting...", module);
            } catch (java.lang.InterruptedException e) {
                Debug.logError(e, module);
            }
        }
        return this.getResult();
    }
}