The jeromq3-x from zeromq

jeromq3-x's Introduction

#JeroMQ

Pure Java implementation of libzmq (http://zeromq.org)

Features

based on libzmq 3.2.2
ZMTP/2.0 (http://rfc.zeromq.org/spec:15)
tcp:// protocol and inproc:// is compatible with zeromq
ipc:// protocol works only between jeromq (uses tcp://127.0.0.1:port internally)
not too bad performance compared to zeromq
2M messages (100B) per sec
Performance
exactly same develope experience with zeromq and jzmq

Not supported Features

ipc:// protocol with zeromq. Java doesn't support UNIX domain socket.
pgm:// protocol. Cannot find a pgm Java implementation

Extended Features

build your own StreamEngine's Decoder/Encoder
TestProxyTcp
Proxy

Contribution Process

This project uses the C4 process for all code changes. "Everyone, without distinction or discrimination, SHALL have an equal right to become a Contributor under the terms of this contract."

Usage

Add it to your Maven project's pom.xml:

<dependency>
  <groupId>org.zeromq</groupId>
  <artifactId>jeromq</artifactId>
  <version>0.3.3</version>
</dependency>

<!-- for the latest SNAPSHOT -->
<dependency>
  <groupId>org.zeromq</groupId>
  <artifactId>jeromq</artifactId>
  <version>0.3.4-SNAPSHOT</version>
</dependency>

<!-- If you can't find the latest snapshot -->
<repositories>
  <repository>
    <id>sonatype-nexus-snapshots</id>
    <url>https://oss.sonatype.org/content/repositories/snapshots</url>
    <releases>
      <enabled>false</enabled>
    </releases>
    <snapshots>
      <enabled>true</enabled>
    </snapshots>
   </repository>
</repositories>

If your are using the Ant

ant [target]

Also please refer the Wiki

jeromq3-x's People

Contributors

Stargazers

Watchers

jeromq3-x's Issues

Lockup when closing ZContext

Using jeromq 3.2.2 there appears to be an issue when closing ZContext. There's a pretty easy workaround but it would be nice if this worked in the way I expect as that would support Java 1.7 "try-with-resource" constructs. Or maybe my understanding of how this is meant to work is incorrect?

I would like to write code like this:

// Initialise ZMQ
try (ZContext z_context = new ZContext()) {

    // Create a response socket
  try (Socket z_responder = z_context.createSocket(ZMQ.ZMQ_REP)) {

      z_responder.bind("tcp://*:5555");
      try {
        // Normally we'd do stuff here....
      }
      finally {
        z_responder.disconnect("tcp://*:5555");
      }

  }
}  // Issue - lock up in implicit close of context here

But this locks up when the context is closed.

The lockup appears to be casued by a NullPointerException in Ctx.destroy_socket().

Exception in thread "reaper-1" java.lang.NullPointerException
    at zmq.Ctx.destroy_socket(Ctx.java:333)
    at zmq.ZObject.destroy_socket(ZObject.java:144)
    at zmq.SocketBase.check_destroy(SocketBase.java:964)
    at zmq.SocketBase.start_reaping(SocketBase.java:779)
    at zmq.Reaper.process_reap(Reaper.java:133)
    at zmq.ZObject.process_command(ZObject.java:114)
    at zmq.Reaper.in_event(Reaper.java:90)
    at zmq.Poller.run(Poller.java:237)
    at java.lang.Thread.run(Unknown Source)

This is the work around - by not closing the socket.

// Initialise ZMQ
try (ZContext z_context = new ZContext()) {

    // Create a response socket
  @SuppressWarnings("resource") // Have to suppress this warning about not closing
  Socket z_responder = z_context.createSocket(ZMQ.ZMQ_REP);

  try {
      z_responder.bind("tcp://*:5555");

      try {
        // Normally we'd do stuff here....
      }
      finally {
        z_responder.disconnect("tcp://*:5555");
      }

  }
  finally {
      // Don't close the socket here else the context will lock 
      // z_responder.close();
  }
}

Recommend Projects