spark2.1源码分析1：Win10下IDEA源码阅读环境的搭建

环境：win10、IDEA2016.3、maven3.3.9、git、scala 2.11.8、java1.8.0_101、sbt0.13.12

下载：

#git bash中执行：
git clone https://github.com/apache/spark.git
git tag
git checkout v2.1.0-rc5
git checkout -b v2.1.0-rc5

导入IDEA，开始调试：
file–open–选中根目录pom.xml，open as project

编译：
等待IDEA index文件完成

打开Maven Project–Profiles–勾选：hadoop-2.6、yarn
点击import changes，再次等待IDEA index文件完成

Maven Project–Generate Sources and Update Folders For All Projects

mvn -T 6 -Pyarn -Phadoop-2.6 -DskipTests clean package
bin/spark-shell

错误：

Exception in thread "main" java.lang.ExceptionInInitializerError
        at org.apache.spark.package$.<init>(package.scala:91)
        at org.apache.spark.package$.<clinit>(package.scala)
        at org.apache.spark.repl.SparkILoop.printWelcome(SparkILoop.scala:81)
        at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply$mcZ$sp(ILoop.scala:921)
        at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply(ILoop.scala:909)
        at scala.tools.nsc.interpreter.ILoop$$anonfun$process$1.apply(ILoop.scala:909)
        at scala.reflect.internal.util.ScalaClassLoader$.savingContextLoader(ScalaClassLoader.scala:97)
        at scala.tools.nsc.interpreter.ILoop.process(ILoop.scala:909)
        at org.apache.spark.repl.Main$.doMain(Main.scala:68)
        at org.apache.spark.repl.Main$.main(Main.scala:51)
        at org.apache.spark.repl.Main.main(Main.scala)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:738)
        at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:187)
        at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:212)
        at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:126)
        at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
Caused by: org.apache.spark.SparkException: Error while locating file spark-version-info.properties
        at org.apache.spark.package$SparkBuildInfo$.liftedTree1$1(package.scala:75)
        at org.apache.spark.package$SparkBuildInfo$.<init>(package.scala:61)
        at org.apache.spark.package$SparkBuildInfo$.<clinit>(package.scala)
        ... 20 more
Caused by: java.lang.NullPointerException
        at java.util.Properties$LineReader.readLine(Properties.java:434)
        at java.util.Properties.load0(Properties.java:353)
        at java.util.Properties.load(Properties.java:341)
        at org.apache.spark.package$SparkBuildInfo$.liftedTree1$1(package.scala:64)

解决方法：
查看spark-core的pom.xml,会发现：

<plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-antrun-plugin</artifactId>
        <executions>
          <execution>
            <phase>generate-resources</phase>
            <configuration>
              <!-- Execute the shell script to generate the spark build information. -->
              <target>
                <exec executable="bash">
                  <arg value="${project.basedir}/../build/spark-build-info"/>
                  <arg value="${project.build.directory}/extra-resources"/>
                  <arg value="${project.version}"/>
                </exec>
              </target>
            </configuration>
            <goals>
              <goal>run</goal>
            </goals>
          </execution>
        </executions>
      </plugin>

此处因为文件路径问题，脚本执行失败，所以没有正常生成spark-version-info.properties文件。手动执行（spark-tags_2.11根据变量自己查找得出），因为没有安装模拟linux的环境，所以这句在git bash中执行：

build/spark-build-info /f/spark2/spark/core/target/extra-resources  spark-tags_2.11

sparkassembly argetscala-2.11jars中找到：spark-core_2.11-2.2.0-SNAPSHOT.jar
查看包内根目录是否有文件：spark-version-info.properties，如果没有添加进去，再尝试bin/spark-shell

加断点运行org.apache.spark.examples.SparkPi，在VM参数中添加-Dspark.master=local[*]，点击执行等待build完成。

错误：

Exception in thread "main" java.lang.NoClassDefFoundError: scala/collection/Seq
    at org.apache.spark.examples.SparkPi.main(SparkPi.scala)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)
Caused by: java.lang.ClassNotFoundException: scala.collection.Seq
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 6 more

Process finished with exit code 1

解决方法：
Menu -> File -> Project Structure -> Modules -> spark-examples_2.11 -> Dependencies 添加依赖 jars -> {spark dir}/spark/assembly/target/scala-2.11/jars/

错误：

Error:(45, 66) not found: type SparkFlumeProtocol

解决方法：

将子项目spark-streaming-flume-sink_2.11的compiled_avro也作为源码目录，等待构建完成。