小编kou*_*kou的帖子

我正在尝试在Ubuntu 11.10上安装Hadoop.我将JAVA_HOME文件中的变量设置conf/hadoop-env.sh为:

# export JAVA_HOME=/usr/lib/jvm/java-1.6.0-openjdk

然后我执行这些命令(独立操作):

$ mkdir input 
$ cp conf/*.xml input 
$ bin/hadoop jar hadoop-examples-*.jar grep input output 'dfs[a-z.]+' 
$ cat output/*

但执行第三个命令时出现以下错误:

错误:未设置JAVA_HOME

是JAVA_HOME不正确的变量？

我有一个maven Entreprise应用程序项目.我在EJB项目中创建了持久性单元,实体类和EJB会话Bean.我尝试构建项目时出现此错误:

无法在项目上执行目标Blog6-ejb:无法解析项目com.mycompany的依赖项:Blog6-ejb:ejb:1.0-SNAPSHOT:无法解析以下工件:org.eclipse.persistence:eclipselink:jar:2.2. 0,org.eclipse.persistence:javax.persistence:jar:2.0.3,org.eclipse.persistence:org.eclipse.persistence.jpa.modelgen.processor:jar:2.2.0:找不到org.eclipse.persistence :eclipselink:jar:2.2.0在 http://ftp.ing.umu.se/mirror/eclipse/rt/eclipselink/maven.repo缓存在本地存储库中,在eclipselink的更新间隔之前不会重新尝试解析已经过了或强制更新 - > [帮助1]

这是pom.xml中的代码

    <?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>Blog6</artifactId>
<groupId>com.mycompany</groupId>
<version>1.0-SNAPSHOT</version>
</parent>

<groupId>com.mycompany</groupId>
<artifactId>Blog6-ejb</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>ejb</packaging>

<name>Blog6-ejb</name>

<properties>
<endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<netbeans.hint.deploy.server>gfv3ee6</netbeans.hint.deploy.server>
</properties>

<dependencies>
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>eclipselink</artifactId>
<version>2.2.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>javax.persistence</artifactId>
<version>2.0.3</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.eclipse.persistence</groupId>
<artifactId>org.eclipse.persistence.jpa.modelgen.processor</artifactId>
<version>2.2.0</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>6.0</version>
<scope>provided</scope>
</dependency>

<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.2</version>
<scope>test</scope>
</dependency>

</dependencies>

<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
<compilerArguments>
<endorseddirs>${endorsed.dir}</endorseddirs>
</compilerArguments>
</configuration> …