Develop Reference

Using Ant to build dependencies of the current build target

Say I have a library and a binary target, let's call them MyLib and MyBin,
MyBin depends on MyLib.
I'm trying to create an Ant buildfile for MyBin that first builds MyLib and then includes it in the classpath when building MyBin.
I've tried using Ant tasks as in Building other, dependent projects with Ant .
However, it's not working, and from ant -v I think the MyBin build-deps target is not even building MyLib. Seems like it's confusing MyBin and MyLib properties? I'm not sure how to prevent this though.
I'm dumping only MyBin/build.xml below, but the MyLib is almost identical, except it does not have the build-deps target.
<project name="MyBin" default="main" basedir=".">
<property name="projectName" value="MyBin" />
<property name="src.dir" location="src" />
<property name="build.dir" location="bin" />
<property name="dist.dir" location="dist" />
<property name="dist.lib.dir" location="dist/lib" />
<property name="lib.dir" value="lib" />
<target name="build-deps" depends="init">
<!-- MyLib main target does clean -> build -> jar to dist folder -->
<!-- Its build.xml uses many of the same property values as above -->
<ant antfile="../MyLib/build.xml" target="main"/>
</target>
<path id="classpath">
<fileset dir="${basedir}/">
<include name="../MyLib/dist/**/*.jar" />
</fileset>
</path>
<!-- Need classpath to run this -->
<target name="compile" depends="build-deps" description="compile the source ">
<javac includeantruntime="false" srcdir="${src.dir}"
destdir="${build.dir}" classpathref="classpath" />
</target>
<!-- Group all dependencies into a big dependency-all.jar -->
<target name="copy-dependencies">
<mkdir dir="${dist.lib.dir}" />
<jar jarfile="${dist.lib.dir}/dependencies-all.jar">
<zipgroupfileset dir="${lib.dir}">
<include name="**/*.jar" />
</zipgroupfileset>
</jar>
</target>
<!-- jar it, extract above dependency-all.jar and zip it with project files -->
<target name="jar" depends="compile, copy-dependencies"
description="package, output to JAR">
<mkdir dir="${dist.dir}" />
<mkdir dir="${dist.lib.dir}" />
<jar jarfile="${dist.dir}/${projectName}.jar" basedir="${build.dir}">
<manifest>
<attribute name="Main-Class" value="${main-class}" />
</manifest>
<zipfileset src="${dist.lib.dir}/dependencies-all.jar"
excludes="META-INF/*.SF" />
</jar>
</target>
<target name="clean" description="clean up">
<delete dir="${build.dir}" />
<delete dir="${dist.dir}" />
</target>
<!-- Default, run this -->
<target name="main" depends="clean, compile, jar" />
</project>
What I see with ant -v in MyBin is something along the lines of:
build-deps:
Project base dir set to: /MyBin
[ant] calling target(s) [main] in build file /MyLib/build.xml
parsing buildfile /MyLib/build.xml with URI = file:/MyLib/build.xml
Project base dir set to: /MyBin
Override ignored for property "projectName"
Override ignored for property "build.dir"
Override ignored for property "dist.dir"
Override ignored for property "dist.lib.dir"
Override ignored for property "lib.dir"
[pathconvert] Set property classpath.name =
[ant] Entering /MyLib/build.xml...
Build sequence for target(s) `main' is [clean, init, copy-dependencies, jar, main]
Complete build sequence is [clean, init, copy-dependencies, jar, main, ]
clean:
[delete] Deleting directory /MyBin/bin
[delete] Deleting directory /MyBin/bin
init:
[mkdir] Created dir: /MyBin/bin
copy-dependencies:
[ant] Exiting /MyLib/build.xml.

On your specific question:
seems like it's confusing MyBin and MyLib properties? I'm not sure how
to prevent this though.
You are using this to invoke the MyLib build:
<ant antfile="../MyLib/build.xml" target="main" />
A build invoked via the <ant> task this way by default inherits all properties from the caller, including basedir, hence the build is run in the wrong place.
Instead you could use, for example:
<ant dir="../MyLib" />
That will run build.xml in the specified directory, set the basedir property, and call the default target, which should be main if you are using a very similar buildfile for the library as you say. If you don't want to inherit properties from MyBin when executing the MyLib task, specify inheritAll=false in the task.
From the <ant> task docs for the dir attribute:
the directory to use as a basedir for the new Ant project (unless
useNativeBasedir is set to true). Defaults to the current project's
basedir, unless inheritall has been set to false, in which case it
doesn't have a default value. This will override the basedir setting
of the called project. Also serves as the directory to resolve the
antfile and output attribute's values (if any).

java.util.logger.Logging: keeping logger.properties file outside the jar file

In my project I have a properties file which I use to set the level of logging. Now when I export my project as a jar and use it to run the project on a remote machine (linux), I cannot set the level. Is there a way to keep the properties file outside the jar file such that I can set the level and make the jar read that properties file. (preferred using environment variable)

There are several ways to achieve this, for example:
Configure your IDE to export resources outside the JAR: usually I don't consider this option since the specific solution depends by the developer's IDE
Use a generic build tool, for example Ant, and specify in the build.xml file which properties files should be packaged outside the jar
Integrate your project with Maven and customize the package goal in order to copy some specific properties file outside jar
From your question I guess you are exporting the JAR from your IDE, but as I stated above the solution depends by the IDE. For this reason, in order to adopt an IDE independent solution, I would suggest to use Ant. This would allow you to solve this and many similar issues that could arise in the future.
You can get Ant here: just download and unpackage it in any folder, it takes a couple of minutes. Then add a reference to Ant bin directory in your PATH variable (not strictly necessary but suggested) and create a sample build.xml file. Here it is a template example:
<project name="template" default="compile" basedir=".">
<description>Build file template</description>
<property name="project.name" value="myProject"/>
<property name="driver.log" value="log4j-1.2.15.jar"/>
<property name="driver.database" value="ojdbc6.jar"/>
<property name="library.home" value="lib"/>
<property name="env.type" value="dev"/>
<property name="src.version" value="Demo" />
<property name="src.folder" value="root/folder/template"/>
<property name="src.package" value="root.folder.template"/>
<property name="src.home" value="${basedir}/src/${src.folder}"/>
<property name="dist.home" value="${basedir}/dist"/>
<property name="build.home" value="${basedir}/build"/>
<property name="docs.home" value="${basedir}/docs"/>
<!-- Setting the classpath necessary to compile -->
<path id="compile.classpath">
<pathelement location="${library.home}/${driver.log}"/>
<pathelement location="${library.home}/${driver.database}"/>
</path>
<!-- DELETE the class files from the ${build.home} directory tree -->
<target name="clean" description="Clean up the build folder">
<delete dir="${build.home}"/>
<delete dir="${dist.home}"/>
</target>
<!-- CREATE the build directory structure used by compile -->
<target name="init" description="Creates the necessary directories">
<mkdir dir="${dist.home}"/>
<mkdir dir="${build.home}"/>
</target>
<!-- COMPILE the project and copy all necessary resources -->
<!-- Options: <compilerarg value="-Xlint"/> -->
<target name="compile" depends="init" description="Compile the sources">
<javac srcdir="${src.home}" destdir="${build.home}" includeantruntime="false">
<classpath refid="compile.classpath"/>
</javac>
<copy todir="${build.home}/${src.folder}/resources">
<fileset dir="${src.home}/resources">
<include name="messages_list.properties"/>
<include name="messages_list_en.properties"/>
</fileset>
</copy>
<copy file="${src.home}/resources/log4j_${env.type}.properties" tofile="${build.home}/${src.folder}/resources/log4j_${project.name}.properties"/>
<copy file="${src.home}/resources/configuration_${env.type}.properties" tofile="${build.home}/${src.folder}/resources/${project.name}_config.properties"/>
</target>
<!-- Creates the DISTRIBUTABLE JAR package and add 3d part libraries -->
<target name="dist" description="Create the distributable JAR archive">
<jar destfile="${dist.home}/${project.name}.jar">
<fileset dir="${build.home}">
<exclude name="place_holder\"/>
</fileset>
<!-- Setting MANIFEST properties -->
<manifest>
<section name="${ant.project.name} - ver. ${src.version}">
<attribute name="Built_By" value="${user.name}"/>
<attribute name="Created" value="${ts}"/>
</section>
<attribute name="Main-Class" value="package.mine.MainClass"/>
<attribute name="Class-Path" value=". lib/${driver.log} lib/${driver.database}"/>
</manifest>
</jar>
<!-- Adding third part libraries -->
<mkdir dir="${dist.home}/lib"/>
<copy file="${library.home}/${driver.database}" todir="${dist.home}/lib"/>
<copy file="${library.home}/${driver.log}" todir="${dist.home}/lib"/>
</target>
<tstamp><format property="ts" pattern="dd/MM/yyyy HH:mm:ss" /></tstamp>
</project>
Remark: in the template above you should replace the sample JARS (log4j and the OJDBC driver) with the actual JARS needed by your project. Then you can customize the copy task in order to place the properties files where you wish. You can copy those file in any directory you like, as long as such path appears in the application's classpath.

Task dependency order in Ant

I am trying to learn ant and found an example build file in the docs.
<project name="MyProject" default="dist" basedir=".">
<description>
simple example build file
</description>
<!-- set global properties for this build -->
<property name="src" location="src"/>
<property name="build" location="build"/>
<property name="dist" location="dist"/>
<target name="init">
<!-- Create the time stamp -->
<tstamp/>
<!-- Create the build directory structure used by compile -->
<mkdir dir="${build}"/>
</target>
<target name="compile" depends="init"
description="compile the source">
<!-- Compile the java code from ${src} into ${build} -->
<javac srcdir="${src}" destdir="${build}"/>
</target>
<target name="dist" depends="compile"
description="generate the distribution">
<!-- Create the distribution directory -->
<mkdir dir="${dist}/lib"/>
<!-- Put everything in ${build} into the MyProject-${DSTAMP}.jar file -->
<jar jarfile="${dist}/lib/MyProject-${DSTAMP}.jar" basedir="${build}"/>
</target>
<target name="clean"
description="clean up">
<!-- Delete the ${build} and ${dist} directory trees -->
<delete dir="${build}"/>
<delete dir="${dist}"/>
</target>
</project>
I'm assuming the clean step should run before the init step however neither step depends on the other. Should init depend on clean step? If not, how does ant know the proper order?

When this ant build file runs, the clean target will not be executed. It isn't in the dependency chain. You would have to explicitly trigger it form the command line, e.g.
ant -f _buildFile.xml clean
ant -f _buildFile.xml
I've done that within a bash file. This is an example file, though, so it isn't necessarily how your final build system will work.
Maybe doing a dist should do clean first (seems reasonable), but that should be part of the dist dependencies, not the init target. For instance, you might want to compile and not do a clean. So
<target name="dist" depends="clean, compile"...
Or you could add a new target, clean_dist, for instance and add the dependency there. Then you could do a quick distribution build and real distribution build by specifying the target on the command line.

How can I build my jar file so that users who use the library will be able to see the javadoc in Eclipse

I'm working on a small library for our in-company use, and have been heavily documenting it. Now I'm building my jar with the following code:
<project name="commonutils" default="compile" basedir=".">
<property name="src" location="src" />
<property name="build" location="buildDirecotry" />
<target name="compile">
<delete file="${ant.project.name}.jar" />
<mkdir dir="${build}"/>
<javac srcdir="${src}" destdir="${build}" debug="on" target="1.5">
<classpath>
<pathelement location="lib/build/server.zip" />
<pathelement path="${java.class.path}/"/>
</classpath>
</javac>
<jar basedir="${build}" destfile="${ant.project.name}.jar" />
<delete dir="${build}" />
</target>
</project>
Which works fine, it builds my jar file with all the src files in it, but when I include the jar file in another project I no-longer have any of my javadoc comments. Using JDDecompiler I cannot see the comments in the class file, although I'm not sure if its the java compiler that's stripping them or JD.
My question is: How can I build my jar file so that users who use the library will be able to see the javadoc in Eclipse.

If you include the source files in the jar (each class and java file in the same package-directory) it should work.
<target name="jar.noCompile.src">
<jar destfile="${ant.project.name}.jar">
<fileset dir="${build}"/>
<fileset dir="${src}" includes="**/*.java"/>
</jar>
</target>

AFAIK the documentation is an Eclipse feature. You have to configure it manually. In your build generate the documentation (usually into folder 'javadoc') and package it with the JAR. Once someone wants to use your library, he/she has to go into Java Build Path select libraries, add yours, click next to it to open the tree node and then double click on Javadoc location to configure it.

How to include the lib folder in the manifest classpath in Netbeans

A library that my java application uses needs looks for a file (log4j.xml) in the class path. I use netbeans to manage my project, but I can't find a way to include the lib/ folder.
Netbeans automatically creates a MANIFEST.MF file inside the application jar and also creates a folder called lib/ which includes all dependencies. This manifest specifies a Class-Path attribute that overrides any -cp argument provided on the command line. I can select an arbitrary folder in netbeans' library panel, but it creates a sub folder in the manifest's classpath. I'd like all dependencies and the log4j.xml file inside the lib/ folder.
Hopefully it's possible to do this in the IDE. I include a snippet of the auto-generated build-impl.xml file.
<target depends="init,compile,-pre-pre-jar,-pre-jar" if="manifest.available+main.class+mkdist.available" name="-do-jar-with-libraries">
<property location="${build.classes.dir}" name="build.classes.dir.resolved"/>
<pathconvert property="run.classpath.without.build.classes.dir">
<path path="${run.classpath}"/>
<map from="${build.classes.dir.resolved}" to=""/>
</pathconvert>
<pathconvert pathsep=" " property="jar.classpath">
<path path="${run.classpath.without.build.classes.dir}"/>
<chainedmapper>
<flattenmapper/>
<globmapper from="*" to="lib/*"/>
</chainedmapper>
</pathconvert>
<taskdef classname="org.netbeans.modules.java.j2seproject.copylibstask.CopyLibs" classpath="${libs.CopyLibs.classpath}" name="copylibs"/>
<copylibs compress="${jar.compress}" jarfile="${dist.jar}" manifest="${manifest.file}" runtimeclasspath="${run.classpath.without.build.classes.dir}">
<fileset dir="${build.classes.dir}"/>
<manifest>
<attribute name="Main-Class" value="${main.class}"/>
<attribute name="Class-Path" value="${jar.classpath}"/>
</manifest>
</copylibs>
<echo>To run this application from the command line without Ant, try:</echo>
<property location="${dist.jar}" name="dist.jar.resolved"/>
<echo>java -jar "${dist.jar.resolved}"</echo>
</target>
Thanks.

Instead of editing the build-impl.xml file you should add this entry to the build.xml file. When you modify anything in your project pertaining to the building of that project, it will generate a new build-impl.xml file.
Here is an example of what I put in my build.xml file:
<target depends="init" name="-do-clean">
<delete dir="${build.dir}"/>
<delete file="${dist.jar}"/>
<delete dir="${dist.dir}/lib"/>
<delete dir="${dist.dir}/resources"/>
</target>
Since I put this in the build.xml file, it will override the "-do-clean" section of the build-impl.xml file which contains:
<target depends="init" name="-do-clean">
<delete dir="${build.dir}"/>
<delete dir="${dist.dir}" followsymlinks="false" includeemptydirs="true"/>
</target>
Furthermore, since it is in the build.xml it won't be modified by Netbeans.

I found a way to acheive this modifying the build-impl.xml.
I changed:
<attribute name="Class-Path" value="${jar.classpath}"/>
to:
<attribute name="Class-Path" value="${jar.classpath} /lib"/>
The problem is that netbeans will overwrite it since this file is automatically generated.

You can simply turn off project option Build/Packaging/Copy Dependent Library and manualy edit manifest.mf in root folder of your project (which is a template for manifest in jar file).

It seems that your problem is the "globmapper" that stores your log4j.xml file in /lib - you'd want it on the "/" or the jar.