java.library.path中没有jzmq

Question

我在一个交易引擎上工作，在运行时，我从engine.log获得日志，如下所示，

2018_01_02_03_28_20_684 INFO  ZMQCommunicatorService REMOTE_EXECUTOR_MARKET_ADMIN-ALL_MARKETS-0-5 - no jzmq in java.library.path, sleeping 2 minutes then try again
2018_01_02_03_28_20_697 INFO  ZMQCommunicatorService ENGINE_MARKET_ADMIN-ALL_MARKETS-0-4 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_30_20_696 INFO  ZMQCommunicatorService REMOTE_EXECUTOR_MARKET_ADMIN-ALL_MARKETS-0-5 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_30_20_710 INFO  ZMQCommunicatorService ENGINE_MARKET_ADMIN-ALL_MARKETS-0-4 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_32_20_697 INFO  ZMQCommunicatorService REMOTE_EXECUTOR_MARKET_ADMIN-ALL_MARKETS-0-5 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_32_20_711 INFO  ZMQCommunicatorService ENGINE_MARKET_ADMIN-ALL_MARKETS-0-4 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_34_20_698 INFO  ZMQCommunicatorService REMOTE_EXECUTOR_MARKET_ADMIN-ALL_MARKETS-0-5 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_34_20_712 INFO  ZMQCommunicatorService ENGINE_MARKET_ADMIN-ALL_MARKETS-0-4 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_36_20_699 INFO  ZMQCommunicatorService REMOTE_EXECUTOR_MARKET_ADMIN-ALL_MARKETS-0-5 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again
2018_01_02_03_36_20_713 INFO  ZMQCommunicatorService ENGINE_MARKET_ADMIN-ALL_MARKETS-0-4 - Could not initialize class org.zeromq.ZMQ, sleeping 2 minutes then try again

我相信第一行说明了主要问题，

No jzmq in java.library.path

我遵循了ZMQ binding for Java的设置手册，

cd /root
wget https://github.com/zeromq/jzmq/archive/v3.1.0.tar.gz -O jzmq-3.1.0.tar.gz
tar zxf jzmq-3.1.0.tar.gz
cd jzmq-3.1.0
./autogen.sh
./configure --prefix=/opt/jzmq-3.1.0
nice make
make install

加载项目后，需要在项目根目录中运行命令，

root@debian:~# export LD_LIBRARY_PATH=/opt/jzmq-3.1.0/lib

root@debian:~# java -Xss256k -cp /opt/jzmq-3.1.0/share/java/zmq.jar:draglet-common/target/lib/*:draglet-balser/target/lib/*:draglet-engine/target/lib/*:draglet-remote/target/lib/*:draglet-mapu/target/lib/*:draglet-shaba/target/lib/*:draglet-meba/target/lib/* -Dlog4j.configurationFile=draglet-common/src/main/resources/log4j2.xml -DisThreadContextMapInheritable=true com.draglet.batch.Batch draglet.yml

当我得到这样的输出时，

Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.

Tue Jan 02 03:59:17 EST 2018 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.

这个问题是否与Intellij终端中提供的警告有关？如何检查jzmq是否在java.library.path中？

Answer 1

好的。所以，让我们一起把手弄脏：

若要在您的机器上查看是否按应有的方式工作，请在适当安装后，或不安装：

最简单的形式原型之一是一个REQ/REP示例，它使用两个部分，一个是“服务器”：

import org.zeromq.ZMQ;
import org.zeromq.ZMQ.Context;
import org.zeromq.ZMQ.Socket;

public class rrserver{
    public static void main (String[] args) {
        Context context = ZMQ.context(1);

        //  Socket to talk to clients
        Socket responder  = context.socket(ZMQ.REP);
        responder.bind("tcp://localhost:5560");

        System.out.println("launch and connect server.");

        while (!Thread.currentThread().isInterrupted()) {
            //  Wait for next request from client
            byte[] request = responder.recv(0);
            String string = new String(request);
            System.out.println("Received request: ["+string+"].");

            //  Do some 'work'
            try {
                Thread.sleep(1);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            //  Send reply back to client
            responder.send("World".getBytes(), 0);
        }

        //  We never get here but clean up anyhow
        responder.close();
        context.term();
    }
}

另一部分，“客户”：

import org.zeromq.ZMQ;
import org.zeromq.ZMQ.Context;
import org.zeromq.ZMQ.Socket;

public class rrclient{

    public static void main(String[] args) {
        Context context = ZMQ.context(1);

        //  Socket to talk to server
        Socket requester = context.socket(ZMQ.REQ);
        requester.connect("tcp://localhost:5560"); // REF ABOVE AND LET START THIS AFTER "server"

        System.out.println("launch and connect client.");

        for (int request_nbr = 0; request_nbr < 10; request_nbr++) {
            requester.send("Hello", 0);
            String reply = requester.recvStr(0);
            System.out.println("Received reply " + request_nbr + " [" + reply + "]");
        }

        //  We never get here but clean up anyhow
        requester.close();
        context.term();
    }
}

如果安装是否正确，这应该会很快显示出来。代码是从ZeroMQ发布的一些琐碎的示例中借来的，以获得灵感。

如果真的想进入分布式计算领域，请不要犹豫地阅读Pieter的一本伟大的书，“代码连接，第1卷”(也可在pdf中获得)。值得付出时间和努力。

Answer 2

在OSX上，我也有类似的问题。我安装了ZMQ using these instructions。

最后一步是使用-Djava.library.path=/usr/local/lib设置库路径。

我发现简单地将路径添加到

~/.bash_profile

例如：

echo "export JAVA_LIBRARY_PATH=$JAVA_LIBRARY_PATH:/usr/local/lib" >> ~/.bash_profile

在重新启动Intellij之后，它能够正确地找到libjzmq。

此外，如果您计划进行任何C/C++开发，那么导出DYLD_LIBRARY_PATH也可能是个好主意。

简单地添加

export DYLD_LIBRARY_PATH="$DYLD_LIBRARY_PATH:/usr/local/lib"

至

~/.bash_profile。