org.cyclades.client.message.CompletableMessageProcessor Maven / Gradle / Ivy

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package org.cyclades.client.message;

import org.cyclades.engine.nyxlet.templates.xstroma.message.api.MessageProcessor;

/**
 * Abstract class extending MessageProcessor that allows checking for completion. An example use would be the implementation of a
 * messaging scatter/gather pattern etc.
 */
public abstract class CompletableMessageProcessor implements MessageProcessor {
    
    /**
     * Method to implement that includes logic that will detect if this message aggregation has completed.
     * 
     * @return boolean true if done, false otherwise
     * @throws Exception
     */
    public abstract boolean done () throws Exception;
    
    /**
     * Implementation needs to call this method every time a completion check is necessary
     * 
     * @return done if true, false otherwise
     * @throws Exception
     */
    public boolean checkDone () throws Exception {
        boolean done = done();
        if (done) {
            synchronized (this) {
                notifyAll();
            }
        }
        return done;
    }
    
}