无法找到Javac编译器

我在eclipse中的pom.xml中收到错误消息 .

http://maven.apache.org/maven-v4_0_0.xsd“> 4.0.0 com.hmis chmis war 1.0-SNAPSHOT chmis Maven Webapp http://maven.apache.org

<properties>
    <spring.version>3.0.5.RELEASE</spring.version>
</properties>

<dependencies>

    <!-- Spring 3 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>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>${spring.version}</version>
    </dependency>

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

    <!-- Spring Security -->
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-core</artifactId>
        <version>${spring.version}</version>
    </dependency>

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

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

    <!-- jstl -->
    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>servlet-api</artifactId>
        <version>2.3</version>
    </dependency>

    <!-- MySQL database driver -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.9</version>
    </dependency>



    <!-- My stuff -->
      <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>com.springsource.org.apache.commons.dbcp</artifactId>
        <version>1.2.2.osgi</version>
        <scope>system</scope>
        <systemPath>C:\Documents and Settings\g702881\.m2\repository\org\apache\commons\com.springsource.org.apache.commons.dbcp\1.2.2.osgi\com.springsource.org.apache.commons.dbcp-1.2.2.osgi.jar</systemPath>



    <dependency>
        <groupId>org.codehaus.jackson</groupId>
        <artifactId>jackson-mapper-asl</artifactId>
        <version>1.9.3</version>
    </dependency>

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

    <dependency>
        <groupId>org.apache.commons</groupId>
        <artifactId>com.springsource.org.apache.commons.lang</artifactId>
        <version>2.1.0</version>
        <scope>system</scope>
     <systemPath>C:\Documents and Settings\g702881\.m2\repository\org\apache\commons\com.springsource.org.apache.commons.lang\2.1.0\com.springsource.org.apache.commons.lang-2.1.0.jar</systemPath>


</dependencies>

 <build>
    <finalName>chmis</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.tomcat.maven</groupId>
            <artifactId>tomcat7-maven-plugin</artifactId>
            <version>7</version>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
    </plugins>
</build> 


 <build>
    <finalName>chmis</finalName>
    <plugins>
        <plugin>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
    </plugins>
</build>

这是我的pom.xml . 当我运行该程序时，我得到如下错误 .

[INFO] -------------------------------------------------------------
[ERROR] Unable to locate the Javac Compiler in:
C:\Program Files (x86)\Java\jre6\..\lib\tools.jar
Please ensure you are using JDK 1.4 or above and
not a JRE (the com.sun.tools.javac.Main class is required).
In most cases you can change the location of your Java
installation by setting the JAVA_HOME environment variable.
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.874s
[INFO] Finished at: Tue Jul 29 14:26:12 IST 2014
[INFO] Final Memory: 5M/15M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.3.2:compile     (default-compile) on project chmis: Compilation failure
[ERROR] Unable to locate the Javac Compiler in:
[ERROR] C:\Program Files (x86)\Java\jre6\..\lib\tools.jar
[ERROR] Please ensure you are using JDK 1.4 or above and
[ERROR] not a JRE (the com.sun.tools.javac.Main class is required).
[ERROR] In most cases you can change the location of your Java
[ERROR] installation by setting the JAVA_HOME environment variable.
[ERROR] -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the           following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException