NetCrusher is TCP/UDP proxy framework for Java and a command line tool that could be placed in the middle between any client and server and allows to check both sides for failover.
- emulates network failures
- emulates frozen connection
- supports both TCP and UDP
- supports multiple dynamic connections through the same proxy tunnel
- allows to check the state of connections
- allows to filter/dump data
- supports throttling (delay and/or throughput control)
- garbage-less buffering
- high performance (16.6 Gbits on loopback interface of my laptop)
- supports IP4/IP6
NetCrusher is build on top of Java 8 NIO and has no external dependencies except SLF4J.
Read documentation.
Download latest dist.tar.gz to get the command line tool.
NioReactor reactor = new NioReactor(); TcpCrusher crusher = TcpCrusherBuilder.builder() .withReactor(reactor) .withBindAddress("localhost", 10080) .withConnectAddress("google.com", 80) .buildAndOpen(); // ... some actions // emulate reconnect crusher.reopen(); // ... check the client connection is reestablished successfully // closing crusher.close(); reactor.close();
NioReactor reactor = new NioReactor(); DatagramCrusher crusher = DatagramCrusherBuilder.builder() .withReactor(reactor) .withBindAddress("localhost", 10188) .withConnectAddress("time-nw.nist.gov", 37) .buildAndOpen(); // ... some actions // check data is sent Assert.assertTrue(crusher.getInner().getReadDatagramMeter().getTotal() > 0); // closing crusher.close(); reactor.close();
Checks additional samples in the project root folder:
For manual QA the command-line wrapper is available both for TCP and Datagram mode
$ ./run-tcp-crusher.sh 127.0.0.1:12345 google.com:80
# Version: 0.8
# Print `HELP` for the list of the commands
# enter the command in the next line
CLOSE
[20:19:20.586] INFO TcpCrusher </127.0.0.1:12345>-<google.com/64.233.161.101:80> is closed
[20:19:20.586] INFO Crusher is closed
# enter the command in the next line
OPEN
[20:19:21.655] INFO TcpCrusher </127.0.0.1:12345>-<google.com/64.233.161.101:80> is open
[20:19:21.655] INFO Crusher is open
More about the command line mode in wiki.
<dependency> <groupId>com.github.netcrusherorg</groupId> <artifactId>netcrusher-core</artifactId> <version>0.10</version> </dependency>
See wiki page
Apache License Version 2.0, http://www.apache.org/licenses/LICENSE-2.0.html
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