ZeroMQ--使用jzmq进行编程

http://my.oschina.net/cloudcoder/blog/200989

 

一、环境搭建

wget http://download.zeromq.org/zeromq-2.1.7.tar.gz
tar -xzf zeromq-2.1.7.tar.gz
cd zeromq-2.1.7
./configure
make
sudo make install

git clone https://github.com/nathanmarz/jzmq.git
cd jzmq
./autogen.sh
./configure
make
sudo make install

如果没有安装libtool、libuuid-devel则需要先安装，否则安装失败
yum install libtool
yum install libuuid-devel

常见问题：

出现java.lang.UnsatisfiedLinkError: /usr/local/lib/libjzmq.so.0.0.0: libzmq.so.1: cannot open shared object file: No such file or directory异常 
原因是未找到zmq动态链接库。 
解决方法1：export LD_LIBRARY_PATH=/usr/local/lib 
解决方法2：编辑/etc/ld.so.conf文件，增加一行：/usr/local/lib。再执行sudo ldconfig命令 

Exception in thread "main" java.lang.UnsatisfiedLinkError: no jzmq in java.library.path 
未设置native library 
在eclipse设置native library为/usr/local/lib 
或在jvm增加参数 
-Djava.library.path=/usr/local/lib 
或在启动脚本中增加 
java -Djava.library.path=/usr/local/lib

二、使用jzmq进行编程

    1.创建maven项目，pom.xml的内容参见pom.xml

      注意：jzmq的版本不能太高，建议使用2.1.0，目前storm也是使用这个版本的jzmq-2.1.0.jar

      否则报： java.lang.UnsatisfiedLinkError: org.zeromq.ZMQ$Socket.nativeInit()V

    2.编写Publisher.java,Subscriber.java,参见源代码

    Publisher.java  

package com.catt.mqtest.pubsub;


import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.zeromq.ZMQ;
import org.zeromq.ZMQ.Context;
import org.zeromq.ZMQ.Socket;

public class Publisher {

    // 等待10个订阅者
    private static final int SUBSCRIBERS_EXPECTED = 10 ;
    // 定义一个全局的记录器，通过LoggerFactory获取
    private final static Logger log = LoggerFactory.getLogger(Publisher. class );

    public static void main(String[] args) throws InterruptedException{
        Context context = ZMQ.context( 1 );
        Socket publisher = context.socket(ZMQ.PUB);
        publisher.bind( "tcp://*:5557" );
        try {
            // zmq发送速度太快，在订阅者尚未与发布者建立联系时，已经开始了数据发布
            Thread.sleep( 1000 );
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

        publisher.send( "send start......" .getBytes(), 0 );
        for ( int i = 0 ; i < 10 ; i++) {
            publisher.send(( "Hello world " +i).getBytes(), ZMQ.NOBLOCK);
        }
        publisher.send( "send end......" .getBytes(), 0 );

        publisher.close();
        context.term();
    }
}

Subscriber.java

 

package com.catt.mqtest.pubsub;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.zeromq.ZMQ;
import org.zeromq.ZMQ.Context;
import org.zeromq.ZMQ.Socket;

public class Subscriber {

    // 定义一个全局的记录器，通过LoggerFactory获取
    private final static Logger log = LoggerFactory.getLogger(Subscriber. class );

    public static void main(String[] args) {
        Context context = ZMQ.context( 1 );
        Socket subscriber = context.socket(ZMQ.SUB);
        subscriber.connect( "tcp://192.168.230.128:5557" );
        subscriber.subscribe( "" .getBytes());
        int total = 0 ;
        while ( true ) {
            byte [] stringValue = subscriber.recv( 0 );
            String string = new String(stringValue);
            if (string.equals( "send end......" )) {
                break ;
            }
            total++;
            System.out.println( "Received " + total + " updates. :" + string);
        }

        subscriber.close();
        context.term();
    }
}

pom.xml

 

< project xmlns = "http://maven.apache.org/POM/4.0.0" xmlns:xsi = "http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation = "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" >
    < modelVersion >4.0.0</ modelVersion >

    < groupId >com.catt</ groupId >
    < artifactId >mqtest</ artifactId >
    < version >0.0.1-SNAPSHOT</ version >
    < packaging >jar</ packaging >

    < name >mqtest</ name >
    < url >http://maven.apache.org</ url >

    < properties >
        < project.build.sourceEncoding >UTF-8</ project.build.sourceEncoding >
    </ properties >

    < dependencies >
        < dependency >
            < groupId >org.zeromq</ groupId >
            < artifactId >jzmq</ artifactId >
            < version >2.1.0</ version >
        </ dependency >
        < dependency >
            < groupId >ch.qos.logback</ groupId >
            < artifactId >logback-classic</ artifactId >
            < version >1.1.1</ version >
        </ dependency >
        < dependency >
            < groupId >junit</ groupId >
            < artifactId >junit</ artifactId >
            < version >4.10</ version >
            < scope >test</ scope >
        </ dependency >
    </ dependencies >
</ project >