解决 java.lang.NoSuchMethodError: org.apache.hadoop.fs.FSOutputSummer.(Ljava/util/zip/Checksum;II)V

环境： linux部署hdfs2.6.0集群，windows部署开发环境

为了学习mahout，使用网上的HdfsDAO读写远程hdfs时，ls和mkdir测试通过，但上传文件报错：

Exception in thread "main" java.lang.NoSuchMethodError: org.apache.hadoop.fs.FSOutputSummer.<init>(Ljava/util/zip/Checksum;II)V
at org.apache.hadoop.hdfs.DFSOutputStream.<init>(DFSOutputStream.java:1553)
at org.apache.hadoop.hdfs.DFSOutputStream.<init>(DFSOutputStream.java:1582)
at org.apache.hadoop.hdfs.DFSOutputStream.newStreamForCreate(DFSOutputStream.java:1614)
at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1465)
at org.apache.hadoop.hdfs.DFSClient.create(DFSClient.java:1390)
at org.apache.hadoop.hdfs.DistributedFileSystem$6.doCall(DistributedFileSystem.java:394)
at org.apache.hadoop.hdfs.DistributedFileSystem$6.doCall(DistributedFileSystem.java:390)
at org.apache.hadoop.fs.FileSystemLinkResolver.resolve(FileSystemLinkResolver.java:81)
at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:390)
at org.apache.hadoop.hdfs.DistributedFileSystem.create(DistributedFileSystem.java:334)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:909)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:890)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:787)
at org.apache.hadoop.fs.FileSystem.create(FileSystem.java:776)
at org.playground.HadoopDFSFileReadWrite.main(HadoopDFSFileReadWrite.java:37)
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:497)
at com.intellij.rt.execution.application.AppMain.main(AppMain.java:140)

解决方案：

参考了： http://softdevblogs.com/ 上的相关帖子

发现是 原有的pom中依赖的hadoop2.6因为与mahout 0.11.0依赖的2.4.1版而冲突，实际使用了2.4.1与线上服务器不符

排除掉mahout 0.11.0间接依赖的hadoop设置，只用自己直接设置的hadoop版本号

如：

<!--	mahout -->
<dependency>
<groupId>org.apache.mahout</groupId>
<artifactId>mahout-examples</artifactId>
<version>0.11.0</version>
<exclusions>
<exclusion>
<artifactId>jdk.tools</artifactId>
<groupId>jdk.tools</groupId>
</exclusion>
<exclusion>
<artifactId>hadoop-client</artifactId>
<groupId>org.apache.hadoop</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.mahout</groupId>
<artifactId>mahout-math</artifactId>
<version>0.11.0</version>
</dependency>
<dependency>
<groupId>org.apache.mahout</groupId>
<artifactId>mahout-hdfs</artifactId>
<version>0.11.0</version>
<exclusions>
<exclusion>
<artifactId>hadoop-client</artifactId>
<groupId>org.apache.hadoop</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-common</artifactId>
<version>2.6.0</version>
<exclusions>
<exclusion>
<groupId>jdk.tools</groupId>
<artifactId>jdk.tools</artifactId>
</exclusion>
<exclusion>
<artifactId>jasper-compiler</artifactId>
<groupId>tomcat</groupId>
</exclusion>
<exclusion>
<artifactId>jasper-runtime</artifactId>
<groupId>tomcat</groupId>
</exclusion>
<exclusion>
<artifactId>servlet-api</artifactId>
<groupId>javax.servlet</groupId>
</exclusion>
<exclusion>
<artifactId>jsp-api</artifactId>
<groupId>javax.servlet.jsp</groupId>
</exclusion>
</exclusions>
</dependency>

<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
<version>2.6.0</version>
<exclusions>
<exclusion>
<artifactId>jdk.tools</artifactId>
<groupId>jdk.tools</groupId>
</exclusion>
</exclusions>
</dependency>