我可以通过包含的ANT构建文件运行我的JAR就好了。它运行,并显示输出,以及各种常规的东西。现在,如果我尝试通过命令行java -jar JARFile.jar
运行这个相同的JAR文件,它就会嘶哑。它给出NullPointerException
。好玩,对吧?
违规行代码如下:第3行:
File dir = new File("media/bgs/");
children = dir.list();
int num = (((int) (Math.random()*children.length)));
String choice = children[num];
此代码从jar中的media/bgs
文件和类路径中选择随机背景图像。
提醒:此构建脚本过去已创建可运行的JAR,目前,这些JAR将通过ANT构建文件运行。
思想?
<property name="dir.src" value="src" />
<property name="dir.build" value="build" />
<property name="dir.data" value="data" />
<property name="dir.media" value="media" />
<property name="dir.lib" value="lib" />
<property name="dir.dist" value="dist" />
<property name="name.jar" value="EmpView2.jar" />
<property name="jarpath" value="${dir.dist}/${name.jar}" />
<property file="data/build_info.properties" />
<property name="build.number" value="${build.major.number}.${build.minor.number}.${build.revision.number}" />
<path id="build-classpath">
<pathelement location="${dir.dist}/${name.jar}" />
<fileset dir="${dir.lib}" includes="**/*.jar" />
<fileset dir="${dir.src}" includes="**/*.jar" />
<fileset dir="${dir.data}" includes="**/*" />
<fileset dir="${dir.media}" includes="**/*" />
</path>
<target name="current-number">
<echo>Current build number:${build.number}</echo>
</target>
<target name="dist">
<antcall target="minor">
</antcall>
</target>
<target name="major">
<propertyfile file="data/build_info.properties">
<entry key="build.major.number" type="int" operation="+" value="1" pattern="00" />
<entry key="build.minor.number" type="int" value="0" pattern="00" />
<entry key="build.revision.number" type="int" value="0" pattern="00000" />
</propertyfile>
</target>
<target name="minor">
<propertyfile file="data/build_info.properties">
<entry key="build.minor.number" type="int" operation="+" value="1" pattern="00" />
<entry key="build.revision.number" type="int" value="0" pattern="00000" />
</propertyfile>
</target>
<target name="revision">
<propertyfile file="data/build_info.properties">
<entry key="build.revision.number" type="int" operation="+" value="1" pattern="00000" />
</propertyfile>
</target>
<target name="all">
<propertyfile file="data/build_info.properties">
<entry key="build.major.number" type="int" operation="+" value="1" pattern="00" />
<entry key="build.minor.number" type="int" operation="+" value="1" pattern="00" />
<entry key="build.revision.number" type="int" operation="+" value="1" pattern="00000" />
</propertyfile>
</target>
<target name="clean">
<delete dir="${dir.build}" failonerror="false" />
<delete dir="${dir.dist}" failonerror="false" />
</target>
<target name="prepare">
<mkdir dir="${dir.build}" />
<mkdir dir="${dir.dist}" />
</target>
<target name="compile" depends="prepare">
<depend srcDir="${dir.build}" closure="true" />
<!-- Capture the path as a delimited property using the refid attribute -->
<property name="myclasspath" refid="build-classpath" />
<!-- Emit the property to the ant console -->
<echo message="Classpath = ${myclasspath}" />
<javac srcdir="${dir.src}" destdir="${dir.build}" classpathref="build-classpath" debug="on" includeantruntime="true" />
<unzip dest="${dir.build}">
<fileset dir="${dir.lib}" includes="**/*.zip" />
<fileset dir="${dir.lib}" includes="**/*.jar" />
</unzip>
</target>
<target name="jar" depends="compile">
<manifestclasspath property="lib.list" jarfile="${dir.dist}/${name.jar}">
<classpath refid="build-classpath" />
</manifestclasspath>
<antcall target="revision" />
<jar destfile="${jarpath}" basedir="." includes="${dir.lib}/*" filesetmanifest="mergewithoutmain">
<manifest>
<attribute name="Main-Class" value="com.baesystems.ev2.EmpowerView" />
<attribute name="Class-Path" value="${lib.list}" />
</manifest>
<fileset dir="${dir.build}" includes="**/*" excludes="META-INF/*.SF" />
<fileset dir="." includes="${dir.media}/**/*" />
<fileset dir="." includes="${dir.data}/*" />
</jar>
<chmod file="${dir.dist}/${name.jar}" perm="+x" />
</target>
<target name="run">
<echo message="Attempting to run!" />
<java jar="${jarpath}" fork="true" />
<echo message="JAR launched." />
</target>
<target name="compile-jar-run">
<antcall target="jar" />
<antcall target="run" />
</target>
<target name="clean-compile-jar-run">
<antcall target="clean" />
<antcall target="compile-jar-run" />
</target>