The Protocol Buffers build is managed using Maven

通过maven编译protocol buffers ,

首先要我们要下载protobuf的源码到本地，下载地址：
http://code.google.com/p/protobuf/downloads/detail?name=protobuf-2.5.0.zip

解压后进入x:\protobuf-2.5.0\java,

我们会看到文件：pom.xml以及README.txt，其中README.txt介绍如何使用maven来编译protobuf源码的过程，原文如下：

1) Install Apache Maven if you don't have it:

     http://maven.apache.org/

2) Build the C++ code, or obtain a binary distribution of protoc.  If
   you install a binary distribution, make sure that it is the same
   version as this package.  If in doubt, run:

     $ protoc --version

   You will need to place the protoc executable in ../src.  (If you
   built it yourself, it should already be there.)

3) Run the tests:

     $ mvn test

   If some tests fail, this library may not work correctly on your
   system.  Continue at your own risk.

4) Install the library into your Maven repository:

     $ mvn install

5) If you do not use Maven to manage your own build, you can build a
   .jar file to use:

     $ mvn package

   The .jar will be placed in the "target" directory.

Installation - 'Lite' Version - With Maven

如果你尚未安装maven环境，你可以到上文中描述的地址先下载maven，下载地址：

http://maven.apache.org/

为满足当前的编译需要，你仅需要配置一个MAVEN_HOME，并指定一个maven.bin的的目录即可，如：

在windows系统环境变量内增加：

1、MAVEN_HOME=x:/apache-maven-3.0.5

2、path=%MAVEN_HOME%/bin;

接下来就可以按照README.txt描述的步骤逐一执行即可得到protobuf-java-2.5.0.jar，该文件会保存在当前目录下的target目录内。