java程序运行的扩展
1.带有参数的应用程序运行
Ant在<java>任务中提供了<arg>元素,<arg>有四种属性value,file,line,path
public class Hello {
public static void main(String[] args) {
System.out.println("Hello " + args[0]);
File file = new File(args[1]);
String[] filename = file.list();
for(int i = 0; i < filename.length; i++) {
System.out.println(filename[i]);
}
}
}
build.xml
<?xml version="1.0"?>
<project name="project" default="run">
<property name="run.classpath" value="bin"></property>
<target name="compile">
<javac destdir="bin" srcdir="src"></javac>
</target>
<target name="run" depends="compile">
<java classname="org.ant.chapter1.Hello">
<classpath path="${run.classpath}"></classpath>
<arg value="Ant"/>
<arg file="D:\rag"/>
</java>
</target>
</project>
Buildfile: D:\MyEclipse\workspace\sad\build.xml
compile:
run:
[java] Hello Ant
[java] hello.dat
BUILD SUCCESSFUL
Total time: 734 milliseconds
2.控制新的JVM
一般的<java>任务都运行在当前的JVM中,单一些特定的情况下将Ant运行在新的JVM下面,这时只需要将<java>中的一个属性fork设置为true就可以了.
我们知道,java命令提供了许多的运行参数,用于指定JVM的属性,同样在Ant也提供相应的属性,看例子:
<?xml version="1.0"?>
<project name="project" default="run">
<property name="run.classpath" value="bin"></property>
<property name="Search.JVM.extra.args" value="-Xincgc"></property>
<target name="compile">
<javac destdir="bin" srcdir="src"></javac>
</target>
<target name="run" depends="compile">
<java classname="org.ant.chapter1.Hello" fork="true"
maxmemory="64m">
<classpath path="${run.classpath}"></classpath>
<jvmarg line="${Search.JVM.extra.args}"/>
<arg value="Ant"/>
<arg file="D:\rag"/>
</java>
</target>
</project>
3.运行jar文件,使用failonerror处理错误
<java>同样提供了运行jar文件的属性
MANIFEST.MF
Mainfest-Version: 1.0
Created-By: myth
Sealed: false
Main-Class: org.ant.chapter1.Hello
build.xml
<?xml version="1.0"?>
<project name="project" default="run">
<property name="run.classpath" value="bin"></property>
<property name="Search.JVM.extra.args" value="-Xincgc"></property>
<target name="compile">
<javac destdir="bin" srcdir="src"></javac>
</target>
<target name="jar" depends="compile">
<jar destfile="test.jar" update="true"
manifest="MANIFEST.MF">
<fileset dir="bin">
<include name="**/*.class"/>
</fileset>
</jar>
</target>
<target name="run" depends="jar">
<java fork="true" maxmemory="64m" jar="test.jar">
<classpath path="${run.classpath}"></classpath>
<jvmarg line="${Search.JVM.extra.args}"/>
<arg value="Ant"/>
<arg file="D:\rag"/>
</java>
</target>
</project>
Buildfile: D:\MyEclipse\workspace\sad\build.xml
compile:
jar:
[jar] Updating jar: D:\MyEclipse\workspace\sad\test.jar
run:
[java] Hello Ant
[java] hello.dat
BUILD SUCCESSFUL
Total time: 875 milliseconds
在某些情况下,我们不希望由于一些不重要的任务构建失败,而导致整个构建的失败,所以Ant提供了一个共同的属性-failonerror,多数任务的默认值为failonerror="true",既当此任务构建失败时,失败信息会传递给控制台,并导致build failed,failonerror只支持在新的JVM里运行.
<target name="run" depends="jar">
<java fork="true" maxmemory="64m" jar="test.jar"
failonerror="false" >
<classpath path="${run.classpath}"></classpath>
<jvmarg line="${Search.JVM.extra.args}"/>
<arg value="Ant"/>
<arg file="D:\rag"/>
</java>
</target>
Buildfile: D:\MyEclipse\workspace\sad\build.xml
compile:
jar:
run:
[java] java.lang.NullPointerException
[java] at org.ant.chapter1.Hello.main(Hello.java:27)
[java] Hello Ant
[java] Exception in thread "main"
[java] Java Result: 1
BUILD SUCCESSFUL
Total time: 984 milliseconds
可以看出虽然run构建失败,但是Ant还是执行了,原来的jar文件,并且BUILD SUCCESSFUL!!
使用Ant运行tomcat
Ant使用<exec>任务运行本地程序,先看一个例子:
<?xml version="1.0"?>
<project name="project" default="run">
<target name="run">
<exec executable="cmd">
<arg value="/C a.bat"/>
</exec>
</target>
</project>
a.bat
@echo off
echo Hello >> a.txt
运行完后,会在根目录生成a.txt文件,里面内容为Hello
下面我们来运行tomcat
<?xml version="1.0"?>
<project name="project" default="tomcat-start">
<property name="tomcat.dir" value="c:/Tomcat5"></property>
<target name="tomcat-start">
<exec dir="${tomcat.dir}/bin" executable="cmd">
<env key="CATALINA_HOME" path="${tomcat.dir}"/>
<arg value="/C startup.bat"/>
</exec>
</target>
<target name="tomcat-stop">
<exec dir="${tomcat.dir}/bin" executable="cmd">
<env key="CATALINA_HOME" path="${tomcat.dir}"/>
<arg value="/c shutdown.bat"/>
</exec>
</target>
</project>
成功!!