gr.ntua.h2rdf.client.JavaApiCall.java Source code

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Here is the source code for gr.ntua.h2rdf.client.JavaApiCall.java

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/*******************************************************************************
 * Copyright (c) 2012 Nikos Papailiou.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Public License v3.0
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/gpl.html
 * 
 * Contributors:
 *     Nikos Papailiou - initial API and implementation
 ******************************************************************************/
package gr.ntua.h2rdf.client;

import java.io.IOException;
import java.util.Date;

import org.apache.hadoop.hbase.util.Bytes;
import org.apache.zookeeper.CreateMode;
import org.apache.zookeeper.KeeperException;
import org.apache.zookeeper.WatchedEvent;
import org.apache.zookeeper.Watcher;
import org.apache.zookeeper.ZooKeeper;
import org.apache.zookeeper.Watcher.Event;
import org.apache.zookeeper.ZooDefs.Ids;
import org.apache.zookeeper.data.Stat;
import org.openrdf.query.BindingSet;
import org.openrdf.query.QueryResult;

public class JavaApiCall implements Watcher {
    int deleted;

    private boolean dead;
    private ZooKeeper zk;
    private String filename, root;
    private byte[] outfile;
    private H2RDFConf conf;
    static Integer mutex;

    public JavaApiCall(H2RDFConf conf) {
        this.root = "/in";
        this.conf = conf;
        dead = false;
        filename = "";
        try {
            zk = new ZooKeeper(conf.getAddress(), 3000, this);
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public byte[] send(byte[] value) throws Exception {
        outfile = null;
        long startTimeReal = new Date().getTime();
        try {
            String f = zk.create(root + "/element", value, Ids.OPEN_ACL_UNSAFE, CreateMode.PERSISTENT_SEQUENTIAL);
            filename = "/out/" + f.split("/")[2];
            Stat st = zk.exists(filename, this);
            if (st != null) {
                //System.out.println("Finished ");
                try {
                    dead = true;
                    Stat stat = null;
                    outfile = zk.getData(filename, false, stat);
                    //System.out.println(outfile +"dfsdfsd");
                    zk.delete(filename, 0);
                    synchronized (this) {
                        notifyAll();
                    }
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (KeeperException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            //System.out.println(filename);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (KeeperException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        try {
            synchronized (this) {
                while (!dead) {
                    wait();
                }
            }
        } catch (InterruptedException e) {
            long stopTime = new Date().getTime();
            //System.out.println("Real time in ms: "+ (stopTime-startTimeReal));
        }
        long stopTime = new Date().getTime();
        //System.out.println(outfile);
        return outfile;
    }

    public void process(WatchedEvent event) {
        //System.out.println("message");
        String path = event.getPath();
        if (event.getType() == Event.EventType.None) {
            // We are are being told that the state of the
            // connection has changed
        } else {
            if (path.equals(filename) && (event.getType() == Event.EventType.NodeCreated)) {
                // It's all over
                //System.out.println("Finished ");
                try {
                    dead = true;
                    Stat stat = null;
                    outfile = zk.getData(filename, false, stat);
                    //System.out.println(outfile +"dfsdfsd");
                    zk.delete(filename, 0);
                    synchronized (this) {
                        notifyAll();
                    }
                } catch (InterruptedException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                } catch (KeeperException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }

    }

    public void close() {
        try {
            zk.close();
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}