下面针对Hadoop2.5.0源码讲解源码编译：

编译前的需求：

  • Linux System
  • JDK 1.6+
  • Maven 3.0+
  • Findbugs 1.3.9(if running findbugs)
  • ProtocolBuffer 2.5.0
  • CMake 2.6+(if compiling native code)
  • Zlib devel(if compiling native code)
  • openssl devel(if compiling native hadoop-pipes)
  • Internet connection for first build(to fetch all Maven and Hadoop dependencies)

Maven main modules: hadoop(Main Hadoop Project)

  • hadoop-project(Parent POM for all Hadoop Maven modules)
  • hadoop-project-dist(Parent POM for modules that generate distributions)
  • hadoop-annotations(Generates the Hadoop doclet used to generated the Javadocs)
  • hadoop-assembiles(Maven assembiles used by the different modules)
  • hadoop-common-project(Hadoop Common)
  • hadoop-hdfs-project(Hadoop HDFS)
  • hadoop-mapreduce-project(Hadoop MapReduce)
  • hadoop-tools(Hadoop tools like Streaming, Distcp, etc)
  • hadoop-dist(Hadoop distributions assembler)

Maven build goals:

  • Clean: mvn clean
  • Compile: mvn compile [-Pnative]
  • Run tests: mvn test [-Pnative]
  • Create JAR: mvn package
  • Run findbugs: mvn compile fingbugs:findbugs
  • Run checkstyle: mvn compile checkstyle:checkstyle
  • Install JAR in M2 cache: mvn install
  • Deploy JAR to Maven repo: mvn deploy
  • Run clover: mvn test -Pclover [-DcloverLicenseLocation=${use.name}/.clover.license]
  • Run Rat: mvn apache-rat:check
  • Build javadocs: mvn javadoc:javadoc
  • Build distribution: mvn package [-Pdist][-Pdocs][-Psrc][-Pnative][-Dtar]
  • Change Hadoop version: mvn version:set -DnewVersion=NEWVERSION

Build options:

  • Use -Pnative to compile/bundle native code
  • Use -Pdocs to generate & bundle the documentation in the distribution(using -Pdist)
  • Use -Psrc to create a project source TAR.GZ
  • Use -Dtar to create a TAR with the distribution(using -Pdist)