无法找到javac编译器 [英] Unable to find a javac compiler
问题描述
我试图打包使用Ant我的web应用程序，WAR文件。
I am trying to package my web application into war file using Ant.
当我建，我收到以下错误：
When I build, I am getting the following error:
C:\Documents and Settings\Administrator\workspace\Assignment7\build.xml:67: Unable to find a javac compiler;
com.sun.tools.javac.Main is not on the classpath.
Perhaps JAVA_HOME does not point to the JDK.
It is currently set to "C:\Program Files\Java\jre6"
以下是我的build.xml
The following is my build.xml
<?xml version="1.0" encoding="UTF-8"?>
<project name="Generate War" default="install" basedir=".">
<property name="build.dir" value="build"/>
<property name="dir.name" value="Assignment7"/>
<property name="package.name" value="${dir.name}.war"/>
<property name="content" value="webContent"/>
<property name="web-inf" value="${content}\WEB-INF"/>
<property name="meta-inf" value="${content}\META-INF"/>
<property name="jsp.dir.name" value="${content}"/>
<property name="lib" value="${web-inf}\lib"/>
<property name="src" value="src"/>
<property name="dest.dir" value="target"/>
<!-- Setting path to the server webapp folder -->
<property name="webapp.dir" value="C:\Program Files\Apache Software Foundation\Tomcat 6.0\webapps"/>
<!-- Using temp folder for convinence -->
<property name="temp.dir" value="temp"/>
<property name="temp.dir.web-inf" value="${temp.dir}\WEB-INF"/>
<property name="temp.dir.meta-inf" value="${temp.dir}\META-INF"/>
<property name="temp.dir.lib" value="${temp.dir.web-inf}\lib"/>
<property name="temp.dir.classes" value="${temp.dir.web-inf}\classes"/>
<!--<property name="temp.dir.classes.dir" value="${temp.dir.classes}\**"/>-->
<property name="package.file" value="${dest.dir}\${package.name}"/>
<path id="build.class.path">
<fileset dir="${lib}">
<include name="**/*.jar"/>
</fileset>
</path>
<path id="build.class.path1">
<fileset dir="C:\program files\java\jre6\lib">
<include name="**/*.jar"/>
</fileset>
</path>
<target name="clean">
<delete>
<fileset dir="${dest.dir}" includes="**/*"/>
</delete>
<delete dir="${temp.dir}"/>
<delete dir="${temp.dir.classes}"/>
<delete dir="${temp.dir.web-inf}"/>
<delete dir="${temp.dir.meta-inf}"/>
</target>
<target name="prepare" depends="clean">
<mkdir dir="${dest.dir}"/>
<mkdir dir="${temp.dir}"/>
<mkdir dir="${temp.dir.web-inf}"/>
<mkdir dir="${temp.dir.lib}"/>
<mkdir dir="${temp.dir.classes}"/>
<mkdir dir="${temp.dir.meta-inf}"/>
</target>
<target name="compile" depends="prepare">
<echo>==="complie"===</echo>
<javac srcdir="${src}" destdir="${temp.dir.classes}" debug="on">
<classpath refid="build.class.path"></classpath>
</javac>
<!--<copydir src="${build.dir}\classes" dest="${temp.dir.classes}"/>-->
</target>
<target name="package" depends="compile">
<echo>"PACKAGING THE FILES"</echo>
<copy file="${meta-inf}\MANIFEST.MF" tofile="${temp.dir.meta-inf}\MANIFEST.MF" overwrite="true"/>
<copy file="${web-inf}\web.xml" tofile="${temp.dir.web-inf}\web.xml" overwrite="true"/>
<copy file="${web-inf}\tiles.xml" tofile="${temp.dir.web-inf}\tiles.xml" overwrite="true"/>
<copy todir="${temp.dir.classes}">
<fileset dir="${src}">
<include name="**/*.xml"/>
</fileset>
</copy>
<war destfile="${package.file}" webxml="${temp.dir.web-inf}\web.xml" basedir="${temp.dir}">
<fileset dir="${jsp.dir.name}"/>
<lib dir="${lib}"></lib>
<classes dir="${temp.dir.classes}"></classes>
</war>
</target>
<target name="jsps">
<copy todir="${webapp.dir}\${dir.name}">
<fileset dir="${content}">
<include name="**/*.jsp"/>
<include name="**/*.html"/>
<include name="**/*.css"/>
<include name="**/*.gif"/>
<include name="**/*.jpg"/>
<include name="**/*.png"/>
<include name="**/*.js"/>
</fileset>
</copy>
</target>
<target name="install" depends="package">
<copy file="${package.file}" todir="${webapp.dir}" overwrite="true"/>
</target>
</project>
我怎么能编译没有主类的类文件？
How can I compile a class file that does not have a main class?
我如何设置类路径？
有关参考，我使用Eclipse。
For reference, I am using Eclipse.
推荐答案
您所有蚂蚁的东西会工作，除了javac任务，需要的tools.jar中，位于从JDK / lib目录罚款，JRE是不是足够这种情况下。因此从蚂蚁提示：无法找到javac编译器; ......
All your ant stuff will work fine except the javac task which needs the tools.jar, located in the /lib directory from the JDK, JRE is not sufficient in that case. Therefore the hint from ant : "Unable to find a javac compiler;..."
在使用Eclipse工作的默认设置指向JRE安装。结果
所以，启动Eclipse的第一次应该是你后的第一个步骤之一：结果窗口＆GT; preferences＆GT;已安装的JRE 和JRE更改设置为JDK。结果
或者使用：结果窗口＆GT; preferences＆GT;蚂蚁＆GT;运行＆GT;类路径＆GT;全球条目结果，并从你的JDK / lib文件夹中添加的tools.jar
When working with Eclipse the default setting points to your JRE installation.
So, one of your first steps after starting Eclipse for the first time should be :
Window > Preferences > Installed JREs and change the settings from JRE to JDK.
Alternatively use :
Window > Preferences > Ant > Runtime > Classpath > Global Entries
and add the tools.jar from your JDK/lib folder
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