Java ant构建失败，因为找不到类

Question

我正在学习Java蚂蚁。我在eclipse中创建了一个名为hello world的项目。然后我导出了这个项目，并创建了一个ant构建文件。当我运行ant文件失败时，它抱怨:BUILD FAILEDC:Users**workspaceHelloWorldbuild.xml:31: Class not found: javac1.8

指向这一行:

<javac debug="true" debuglevel="${debuglevel}" destdir="bin" includeantruntime="false" source="${source}" target="${target}">

我正在使用eclipse kepler.

这是我的build.xml文件:

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!-- WARNING: Eclipse auto-generated file.
              Any modifications will be overwritten.
              To include a user specific buildfile here, simply create one in the same
              directory with the processing instruction <?eclipse.ant.import?>
              as the first entry and export the buildfile again. -->
<project basedir="." default="build" name="HelloWorld">
    <property environment="env"/>
    <property name="debuglevel" value="source,lines,vars"/>
    <property name="target" value="1.2"/>
    <property name="source" value="1.3"/>
    <path id="HelloWorld.classpath">
        <pathelement location="bin"/>
    </path>
    <target name="init">
        <mkdir dir="bin"/>
        <copy includeemptydirs="false" todir="bin">
            <fileset dir="src">
                <exclude name="**/*.java"/>
            </fileset>
        </copy>
    </target>
    <target name="clean">
        <delete dir="bin"/>
    </target>
    <target depends="clean" name="cleanall"/>
    <target depends="build-subprojects,build-project" name="build"/>
    <target name="build-subprojects"/>
    <target depends="init" name="build-project">
        <echo message="${ant.project.name}: ${ant.file}"/>
        <javac debug="true" debuglevel="${debuglevel}" destdir="bin" includeantruntime="false" source="${source}" target="${target}">
            <src path="src"/>
            <classpath refid="HelloWorld.classpath"/>
        </javac>
    </target>
    <target description="Build all projects which reference this project. Useful to propagate changes." name="build-refprojects"/>
    <target name="HelloWorld">
        <java classname="HelloWorld" failonerror="true" fork="yes">
            <classpath refid="HelloWorld.classpath"/>
        </java>
    </target>
</project>

有人知道为什么会这样吗?

Answer 1

您的Ant版本是否低于1.9.0?如果是这样，它与java 8不兼容。你最好更新当前版本的Ant。

如果你不使用任何java 8语法，只是想用它来编译，你可以传递"-Dbuild.compiler=javac1.7"到javac