hadoop-2.6.0-src源码导入Eclipse

一.导入

先修改源码 参考 二.改错里面的第3条

1.cd到 hadoop-2.6.0-src/hadoop-maven-plugins

mvn install

2.在cd到hadoop-2.6.0-src 目录下

mvn eclipse:eclipse -DskipTests

3. 在Eclipse中：File-Import-Existing Projects into Workspace 选择hadoop-2.6.0-src目录导入

二.改错

1./hadoop-common/src/test/java/org/apache/hadoop/io/serializer/avro/TestAvroSerialization.java显示找不到AvroRecord类

去http://grepcode.com/file/repo1.maven.org/maven2/org.apache.hadoop/hadoop-common/2.5.0/org/apache/hadoop/io/serializer/avro/AvroRecord.java/ 下载2.5.0或者更高版本的。放到相应位置

2.org.apache.hadoop.ipc 下面没有protobuf文件夹，也缺少相应的java文件，在org.apache.hadoop.ipc下面建立protobuf文件夹，把/hadoop-common/target/generated-sources/java/org/apache/hadoop/ipc/protobuf 里面的响应java文件移到该文件夹下-不要复制，复制会出现重复定义的错误。

3.hadoop-streaming里面的build path有问题，显示home/haodoop/桌面/hadoop-2.6.0-src/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/conf(missing)

我已经把所有源码文件已经导入到Eclipse 的工作目录workspace了，但是它指向的是桌面的源-我之前在 步骤一.导入 时用mvn install ；mvn eclipse:eclipse时的目录，根据网上说 右键hadoop-streaming项目-properties->左边Java Build Path->Source->选定错误项remove掉引用，当时好了，下次打开Eclipse还是有相同的问题。。我对java ，Eclipse不熟，下面是我的解决办法

解决：选中hadoop-streaming项目，在hadoop-stream目录下新建文件夹config，把hadoop-2.6.0-src/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/conf 中的文件拷贝到新建的config下，右键-properties->左边Java Build Path->Source->选定错误项 ，右边有edit

hadoop-streaming目录下的pom.xml文件，找到 ：

<directory>${basedir}/../../hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/conf</directory>
 修改为：
<directory>${basedir}/config</directory> 

然后重新按照 一.导入中的步骤重新mvn intall，mvn eclipse:eclipse，再在Eclipse中删除掉有错的hadoop-streaming项目，然后再导入刚刚mvn生成的hadoop-streaming项目，发现 右键-properties->左边Java Build Path->Source 里面少了conf 出错的项，只有两项了，不放心就又用add Folder新建了一项

Error#1. hadoop-streaming里面的build path有问题，显示/root/workspace/hadoop-2.2.0-src/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/conf(missing)

解决办法，remove掉引用就好。

Error#2. hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSClientFailover.java中报sun.net.spi.nameservice.NameService错误，这是一个需要import的包，存在于openjdk中，在Oracle Jdk中没找到，需要下载一个。NameService是一个接口，在网上找一个NameService放到该包中就好。http://grepcode.com/file/repository.grepcode.com/java/root/jdk/openjdk/7u40-b43/sun/net/spi/nameservice/NameService.java#NameService

Error#3. /hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/tools/offlineEditsViewer/XmlEditsVisitor.java里面显示 
import com.sun.org.apache.xml.internal.serialize.OutputFormat; 
import com.sun.org.apache.xml.internal.serialize.XMLSerializer; 
失败，这是由于Eclipse的强检查原则，打开Java -> Compiler -> Errors/Warnings and under "Deprecated and restricted API" change the setting of "Forbidden reference (access rules)" 将error级别调整到warning级别就好。

Error#4. /hadoop-common/src/test/java/org/apache/hadoop/io/serializer/avro/TestAvroSerialization.java显示没有AvroRecord类，在网上搜索到AvroRecord类放入到同级包中就行了。  http://grepcode.com/file/repo1.maven.org/maven2/org.apache.hadoop/hadoop-common/2.2.0/org/apache/hadoop/io/serializer/avro/AvroRecord.java#AvroRecord

Error#5. org.apache.hadoop.ipc.protobuf包是空的，需要在/hadoop-common/target/generated-sources/java中找到profobuf拷贝到/hadoop-common/src/test/java中就好了. 同时包里面还缺少了以下三个引用，在GrepCode上找一下，把hadoop-common2.2.0的相应文件下下来导入。

org.apache.hadoop.ipc.protobuf.TestProtos.EchoRequestProto;
org.apache.hadoop.ipc.protobuf.TestProtos.EchoResponseProto;
org.apache.hadoop.ipc.protobuf.TestRpcServiceProtos.TestProtobufRpcProto;