HOW TO COMPILE JAVA FILES PROGAMMATICALLY

[Durand Grimmett]

Does anyone have any sample code that will take some java files and compile them programmatically.....that is without using the command prompt?....Any help will be greatly appreciated.

[Tom Blough]

Have a look at this recent
thread

Cheers,

[Durand Grimmett]

The thread that you pointed me to does contain some useful info....but do you have any other examples or sample code that you can refer me too.
I actually just looking for a simple method that I can use, that takes some .java files and compiles them to .class files

Thanks in advance for your help

[Jeff Bosch]

The simplest way that I know of would be to write a batch file that invokes the compiler. You could then schedule the batch file to run at intervals if you wanted. Ant would handle this too, I believe.

[Durand Grimmett]

Question...is it possible to invoke an ant task within a java program? If so how?

next....does anyone have an example of an ant task that compiles java files..........or compiles and jars java files?

[Joe Ess]

Ant tasks are classes. You can invoke them the same way you invoke any other Java class. I think Jeff's way off with the ant suggestion. The thread Tom pointed you has a link to this article which demonstrates how to directly invoke the java compiler. With source code and all.

[sergio mendez-rueda]

Hi Durand,

next....does anyone have an example of an ant task that compiles java files..........or compiles and jars java files?

i think, this simple ant file (build.xml) is the one you are looking for:
<?xml version="1.0"?>
<project name="Java development" default="usage" basedir=".">
<!-- simple ant file
Sun Jun 12 17:40:55 2005
@author s. mendez
-->

<!-- =================================================================== -->
<!-- the name of the wep application -->
<!-- =================================================================== -->

<property name="app.name" value="JavaRanchExemple"/>

<!-- =================================================================== -->
<!-- properties reflecting the directory structur and properties of the -->
<!-- web-app development -->
<!-- =================================================================== -->

<property file="${basedir}/build.properties"/>
<property name="java.src" location="${basedir}/src"/>
<property name="java.src.meta" location="${java.src}/META-INF"/>
<property name="java.src.meta.tags" location="${java.src.meta}/tags"/>
<property name="java.classes" location="${basedir}/classes"/>
<property name="jar.name" value="${app.name}.jar"/>
<property name="dist.dir" location="${basedir}/dist"/>

<!-- =================================================================== -->
<!-- claspath of the wep application -->
<!-- =================================================================== -->
<!--
<path id="build.classpath">
<fileset dir="${tomcat.home}/common/lib/">
<include name="servlet-api.jar"/>
<include name="jsp-api.jar"/>
</fileset>
<fileset dir="${tomcat.home}/common/endorsed/">
<include name="*.jar"/>
</fileset>
<fileset dir="${lib}">
<include name="*.jar"/>
</fileset>
</path>
-->

<!-- =================================================================== -->
<!-- Create the file and directory structure of the web app -->
<!-- =================================================================== -->

<target name="init">
<echo>+ ===================================================== +</echo>
<echo>+ Creating file and directory structure of the app +</echo>
<echo>+ ===================================================== +</echo>
<mkdir dir="${java.src}"/>
<mkdir dir="${java.src.meta}"/>
<mkdir dir="${java.src.meta.tags}"/>
<mkdir dir="${java.classes}"/>
<mkdir dir="${dist.dir}"/>
</target>

<!-- =================================================================== -->
<!-- usage of this file -->
<!-- =================================================================== -->

<target name="usage">
<echo message=""/>
<echo message="your are running the app '${app.name}'"/>
<echo message="-------------------------------------------"/>
<echo message=""/>
<echo message="Available targets are:"/>
<echo message=""/>
<echo message="usage --> this."/>
<echo message="init --> Create the file and directory structure of the app"/>
<echo message="compile --> Compile main source tree java files"/>
<echo message="jarFile --> Build the Jar file"/>
<echo message=""/>
</target>

<!-- =================================================================== -->
<!-- Compiles the source code -->
<!-- =================================================================== -->

<target name="compile" depends="init"
description="Compile main source tree java files">
<echo>+ ===================================================== +</echo>
<echo>+ Compiling java files +</echo>
<echo>+ ===================================================== +</echo>
<javac srcdir="${java.src}" destdir="${java.classes}"> </javac>
</target>

<!-- =================================================================== -->
<!-- Building the Jar file -->
<!-- =================================================================== -->

<target name="jarFile" depends="compile" description="build the jar file">
<echo>+ ===================================================== +</echo>
<echo>+ Building jar files +</echo>
<echo>+ ===================================================== +</echo>
<delete>
<fileset dir="${dist.dir}" includes="${jar.name}" />
</delete>

<jar basedir="${java.classes}" excludes="**" jarfile="${dist.dir}/${jar.name}">
<fileset dir="${java.classes}">
<include name="**/*.class" />
<exclude name="**/web/**/*" />
<exclude name="**/test/**/*" />
</fileset>
<metainf dir="${java.src}/META-INF" includes="*.xml"/>
<metainf dir="${java.src}/META-INF" includes="*.tld"
excludes="application.xml" />
<metainf dir="${java.src}/META-INF/tags" includes="*.tag"/>
</jar>
</target>
</project>

enjoy ant
ser