我正在尝试通过 Spring MVC 应用程序启动 hadoop MapReduce 作业。

MVC 应用程序使用 Apache Tomcat 7.0.62 运行良好。

此外，hadoop 应用程序与 spring-data-hadoop 配合得很好。

当我尝试合并这些项目时，MapReduce 作业初始化崩溃并出现以下错误。

15/05/31 16:10:18 WARN support.ClassPathXmlApplicationContext:      Exception encountered during context initialization - cancelling refresh attempt
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'wordCountJob': Invocation of init method failed; nested exception is java.lang.UnsupportedOperationException: Not implemented by the DistributedFileSystem FileSystem implementation
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1568)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:540)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:229)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
at at.pixsearch.hadoop.Main.go(Main.java:19)
at at.pixsearch.mvc.HelloController.hadoopTest(HelloController.java:22)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:215)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:781)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:721)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:617)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:723)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:620)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.UnsupportedOperationException: Not implemented by the DistributedFileSystem FileSystem implementation
at org.apache.hadoop.fs.FileSystem.getScheme(FileSystem.java:216)
at org.apache.hadoop.fs.FileSystem.loadFileSystems(FileSystem.java:2564)
at org.apache.hadoop.fs.FileSystem.getFileSystemClass(FileSystem.java:2574)
at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2591)
at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:91)
at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2630)
at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2612)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:370)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:169)
at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:354)
at org.apache.hadoop.fs.Path.getFileSystem(Path.java:296)
at org.apache.hadoop.mapreduce.lib.input.FileInputFormat.addInputPath(FileInputFormat.java:372)
at org.springframework.data.hadoop.mapreduce.JobFactoryBean.afterPropertiesSet(JobFactoryBean.java:208)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1627)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1564)

Controller 在“/hadoop”映射中启 Action 业

@Controller
@RequestMapping("/")
public class HelloController {
    @RequestMapping(method = RequestMethod.GET)
    public String printWelcome(ModelMap model) {
        model.addAttribute("message", "Hello world!");
        return "hello";
    }

    @RequestMapping(value = "/hadoop", method= RequestMethod.GET)
    public void hadoopTest() {
       Main.go();
    }
}

主类

public class Main {
    static final Logger logger = LoggerFactory.getLogger(Main.class);    

    public static void go() {
        ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");

    }

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:hdp="http://www.springframework.org/schema/hadoop"
   xmlns:context="http://www.springframework.org/schema/context"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/hadoop 
    http://www.springframework.org/schema/hadoop/spring-hadoop.xsd 
    http://www.springframework.org/schema/context 
    http://www.springframework.org/schema/context/spring-context.xsd">

   <context:property-placeholder location="classpath:application.properties" />

   <hdp:configuration>
          fs.default.name=${hd.fs}
          mapreduce.framework.name=${mr.fw}
          xsrn.resourcemanager.address=${hd.rm}
   </hdp:configuration>

   <hdp:job id="wordCountJob"
            input-path="${input.path}"
            output-path="${output.path}"
            jar-by-class="at.pixsearch.hadoop.Main"
            mapper="at.pixsearch.hadoop.mapper.WordMapper"
            reducer="at.pixsearch.hadoop.reducer.WordReducer"/>

   <hdp:job-runner id="wordCountJobRunner" job-ref="wordCountJob" run-at-startup="true"/>
</beans>

mvc-dispatcher-servlet.xml

<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:mvc="http://www.springframework.org/schema/mvc"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

<context:component-scan base-package="at.pixsearch.mvc"/>

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/pages/"/>
    <property name="suffix" value=".jsp"/>
</bean>

<mvc:annotation-driven/>
<mvc:resources mapping="/resources/**" location="/resources/" />

</beans>

和我的 pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0"   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0   http://maven.apache.org/maven-v4_0_0.xsd">

<modelVersion>4.0.0</modelVersion>
<groupId>com.springapp</groupId>
<artifactId>pixsearch</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>pixsearch</name>

<properties>
    <spring.version>4.1.1.RELEASE</spring.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.5</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet.jsp</groupId>
        <artifactId>jsp-api</artifactId>
        <version>2.1</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-hadoop</artifactId>
        <version>2.1.2.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.apache.hadoop</groupId>
        <artifactId>hadoop-core</artifactId>
        <version>1.0.3</version>
    </dependency>
</dependencies>

<build>
    <finalName>pixsearch</finalName>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
        <plugin>
            <artifactId>maven-surefire-plugin</artifactId>
            <configuration>
                <includes>
                    <include>**/*Tests.java</include>
                </includes>
            </configuration>
        </plugin>
    </plugins>
</build>
</project>

项目结构如下:

-src
    -main
        -java
            -at.pixsearch
                -hadoop
                    -Mapper
                    -Reducer
                    Main.java
                -mvc
                    -HelloController.java
        -resources
            applicationContext.xml
            application.properties
        -webapp
            -resources
                -js
                -css
                -public
                -.....
            -WEB-INF
                -pages
                -mvc-dispatcher-servlet.xml
                -web.xml

我很感激任何帮助或提示:)

最佳答案

我通过 java 而不是 .xml 配置 hadoop 解决了这个问题

所以

@RequestMapping(value="/hadoop" , method = RequestMethod.GET)
public String hadoop(ModelMap model) throws URISyntaxException, IOException {
    String result = null;

    Configuration conf = new Configuration();
    FileSystem fs = FileSystem.get( new URI("hdfs://myhost:9000"), conf);

    Path file = new Path("/user/michael/input/input1.txt");
    FSDataInputStream getIt = fs.open(file);
    BufferedReader d = new BufferedReader(new InputStreamReader(getIt));

    String s = "";
    while ((s = d.readLine()) != null) {
        result += s;
    }
    d.close();
    fs.close();

    model.addAttribute("result", result);
    return "hello";
}

在 Controller 中可以访问 hdfs。

关于java - Spring MVC 和 Apache Hadoop 启动 MapReduce Job，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/30558785/