Help setting up a Java build environment - java

I'm at my wit's end. I'm spending more time working on getting my build to work rather than actually developing software. I'm currently working on large-scale Java web application based on Tomcat 6.
Currently the code-base is about 25k LOC (although that's not quite representative because some of that is autogenerated for web services -- but the take away is that it's big) and I've been working exclusively with eclipse to do everything from debugging, to build path management to building. In the past, eclipse has always been more than enough, but I've never worked on a project this large before.
The first problem I had was when I started adding GWT content. It worked ok, but the build process was a bit hacky: I had to manually compile and then copy the js output into the appropriate directory and debugging was a nightmare (I realize some of those problems are just GWT and the way it works...). Now, the issue I'm running into is attempting to work on the project on a Windows machine (I had been working on a Mac, and will continue to work from a Mac from time to time). Eclipse added the Mac OS JVM libraries to the build path which, of course, Windows can't find.
I asked a question about working in two different environments and most of the answers pertained to using a build tool like Ant+Ivy or Maven. I've started investigating Maven and attempting to get my project to use it, but it's just been one headache after another and I haven't even begun to try to actually execute/debug my application in Tomcat through eclipse. The most frustrating part of all of this is it, to me, seems like these build tools are exceptionally complex (and to be fair, incredibly flexible) but, at least initially, make life even more difficult while you try to figure out how to simply compile a Java file.
So all of that to say, does anybody have suggestions for how to simplify this scenario? Dependency management would be nice, but I don't mind hunting down the JARs myself. The biggest thing I need is something that will just get out of my way and let me work on what I'm actually trying to work on, not spend hours debugging my typos in an xml file used by the build system.
Thanks in advance

I agree. You don't need Maven; you don't need Ivy. Start with Ant.
Here's a relatively generic Ant build.xml. Customize it as you wish.
<?xml version="1.0" encoding="UTF-8"?>
<project name="xslt-converter" basedir="." default="package">
<property name="version" value="1.6"/>
<property name="haltonfailure" value="no"/>
<property name="out" value="out"/>
<property name="production.src" value="src"/>
<property name="production.lib" value="lib"/>
<property name="production.resources" value="config"/>
<property name="production.classes" value="${out}/production/${ant.project.name}"/>
<property name="test.src" value="test"/>
<property name="test.lib" value="lib"/>
<property name="test.resources" value="config"/>
<property name="test.classes" value="${out}/test/${ant.project.name}"/>
<property name="exploded" value="out/exploded/${ant.project.name}"/>
<property name="exploded.classes" value="${exploded}/WEB-INF/classes"/>
<property name="exploded.lib" value="${exploded}/WEB-INF/lib"/>
<property name="reports.out" value="${out}/reports"/>
<property name="junit.out" value="${reports.out}/junit"/>
<property name="testng.out" value="${reports.out}/testng"/>
<path id="production.class.path">
<pathelement location="${production.classes}"/>
<pathelement location="${production.resources}"/>
<fileset dir="${production.lib}">
<include name="**/*.jar"/>
<exclude name="**/junit*.jar"/>
<exclude name="**/*test*.jar"/>
</fileset>
</path>
<path id="test.class.path">
<path refid="production.class.path"/>
<pathelement location="${test.classes}"/>
<pathelement location="${test.resources}"/>
<fileset dir="${test.lib}">
<include name="**/junit*.jar"/>
<include name="**/*test*.jar"/>
</fileset>
</path>
<path id="testng.class.path">
<fileset dir="${test.lib}">
<include name="**/testng*.jar"/>
</fileset>
</path>
<available file="${out}" property="outputExists"/>
<target name="clean" description="remove all generated artifacts" if="outputExists">
<delete dir="${out}" includeEmptyDirs="true"/>
<delete dir="${reports.out}" includeEmptyDirs="true"/>
</target>
<target name="create" description="create the output directories" unless="outputExists">
<mkdir dir="${production.classes}"/>
<mkdir dir="${test.classes}"/>
<mkdir dir="${reports.out}"/>
<mkdir dir="${junit.out}"/>
<mkdir dir="${testng.out}"/>
<mkdir dir="${exploded.classes}"/>
<mkdir dir="${exploded.lib}"/>
</target>
<target name="compile" description="compile all .java source files" depends="create">
<!-- Debug output
<property name="production.class.path" refid="production.class.path"/>
<echo message="${production.class.path}"/>
-->
<javac srcdir="src" destdir="${out}/production/${ant.project.name}" debug="on" source="${version}">
<classpath refid="production.class.path"/>
<include name="**/*.java"/>
<exclude name="**/*Test.java"/>
</javac>
<javac srcdir="${test.src}" destdir="${out}/test/${ant.project.name}" debug="on" source="${version}">
<classpath refid="test.class.path"/>
<include name="**/*Test.java"/>
</javac>
</target>
<target name="junit-test" description="run all junit tests" depends="compile">
<!-- Debug output
<property name="test.class.path" refid="test.class.path"/>
<echo message="${test.class.path}"/>
-->
<junit printsummary="yes" haltonfailure="${haltonfailure}">
<classpath refid="test.class.path"/>
<formatter type="xml"/>
<batchtest fork="yes" todir="${junit.out}">
<fileset dir="${test.src}">
<include name="**/*Test.java"/>
</fileset>
</batchtest>
</junit>
<junitreport todir="${junit.out}">
<fileset dir="${junit.out}">
<include name="TEST-*.xml"/>
</fileset>
<report todir="${junit.out}" format="frames"/>
</junitreport>
</target>
<taskdef resource="testngtasks" classpathref="testng.class.path"/>
<target name="testng-test" description="run all testng tests" depends="compile">
<!-- Debug output
<property name="test.class.path" refid="test.class.path"/>
<echo message="${test.class.path}"/>
-->
<testng classpathref="test.class.path" outputDir="${testng.out}" haltOnFailure="${haltonfailure}" verbose="2" parallel="methods" threadcount="50">
<classfileset dir="${out}/test/${ant.project.name}" includes="**/*.class"/>
</testng>
</target>
<target name="exploded" description="create exploded deployment" depends="testng-test">
<copy todir="${exploded.classes}">
<fileset dir="${production.classes}"/>
</copy>
<copy todir="${exploded.lib}">
<fileset dir="${production.lib}"/>
</copy>
</target>
<target name="package" description="create package file" depends="exploded">
<jar destfile="${out}/${ant.project.name}.jar" basedir="${production.classes}" includes="**/*.class"/>
</target>
</project>

while maven may be a bit daunting at first glance, i think it really is a pretty nice tool. yes, it does have it's warts, but all in all i think it's one of the best choices for java. the "thing" you really need to get about maven is that everything is based on convention. if you do everything the conventional maven way, then your maven pom is generally very small and everything "just works". and there is plenty of getting started info out there to show you what the "maven convention" is. (and yes, you usually can do things your own way, but it's usually not worth it unless you are stuck w/ an existing project which would be difficult to re-organize).

There are alternatives to Ant/Ivy or Maven XML that might be worth a gander. They use a real programming language instead of an XML DSL.
http://buildr.apache.org/ (Ruby based)
http://www.gradle.org/index.php (Groovy based)

One simplification you can use when working solely in Eclipse is to let Eclipse take care of the compilation. A given project can have its own simple Ant script, which packages up whatever is need from bin into a jar.

Related

Need to make a ant build file for eclipse project

I have a simple game implemented in eclipse. It consists of about 8 classes.
It is for my school assignment.
In the turn in specification, there is written:
"Send me all source codes, documentation and ant build file, which allows the project to be compiled and generate javadoc documentation".
I really do not understand how ant works. I googled some tutorials, but I cannot understand them either. I tried to generate build.xml file in eclipse, but the teacher said that this doesnt work either.
Could someone give me some simple steps or give me link to some really basic tutorial? Thanks for help.
This is the eclipse generated ant (export project as antbuildfile):
And it is kind of weird, because the class BasicPaint I deleted a long time ago.
<?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="Snakes_and_Adders">
<property environment="env"/>
<property name="debuglevel" value="source,lines,vars"/>
<property name="target" value="1.8"/>
<property name="source" value="1.8"/>
<path id="Snakes_and_Adders.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="Snakes_and_Adders.classpath"/>
</javac>
</target>
<target description="Build all projects which reference this project. Useful to propagate changes." name="build-refprojects"/>
<target name="BasicPaint">
<java classname="snakes_and_adders.BasicPaint" failonerror="true" fork="yes">
<classpath refid="Snakes_and_Adders.classpath"/>
</java>
</target>
<target name="Game">
<java classname="snakes_and_adders.Game" failonerror="true" fork="yes">
<classpath refid="Snakes_and_Adders.classpath"/>
</java>
</target>
<target name="NewGame">
<java classname="snakes_and_adders.NewGame" failonerror="true" fork="yes">
<classpath refid="Snakes_and_Adders.classpath"/>
</java>
</target>
<target name="PaintingExample">
<java classname="snakes_and_adders.PaintingExample" failonerror="true" fork="yes">
<classpath refid="Snakes_and_Adders.classpath"/>
</java>
</target>
Ant is used to perform tasks that are useful to build applications. You have tasks like <javac> <jar> etc.. To compile your classes and put them in a jar file.
I don't see why the build.xml generated file wouldn't work.. But you can take it as an example to understand how ant works. You can also adapt that build.xml file to make it work anywhere.
This tutorial looks well explained at first sight: http://www.javaworld.com/article/2076208/java-app-dev/automate-your-build-process-using-java-and-ant.html
I find that ant can be pretty complex easily, it'll take you time to understand it well but it's really doable.

Ant creating WAR JAVA

Good day!
I have been trying to write ant file for compilation and making the WAR file for a long time.
But still it doesnt work. At this time I have no build errors, but there is a Tomcat "Resource not found" error, where should be my servlet.
Here is my build.xml:
<?xml version="1.0" ?>
<property environment="env"/>
<property name="dir.src" value="src"/>
<property name="dir.dist" value="ant-dist"/>
<property name="dir.lib" value="WebContent/WEB-INF/lib"/>
<property name="dir.build" value="ant-build"/>
<property name="dir.classes" value="${dir.build}/classes"/>
<property name="tomcat-home" value="${env.TOMCAT_HOME}"/>
<property name="java-home" value="${env.JAVA_HOME}"/>
<path id="compile.classpath">
<fileset dir="${dir.lib}" includes="*.jar"/>
<fileset dir="${tomcat-home}" includes="**/*.jar" />
<fileset dir="${java-home}" includes="**/*.jar" />
</path>
<target name="init">
<mkdir dir="${dir.classes}"/>
<mkdir dir="${dir.dist}" />
</target>
<target name="compile" depends="init" >
<javac destdir="${dir.build}" debug="true" srcdir="${dir.src}" includeantruntime="false">
<classpath refid="compile.classpath"/>
</javac>
</target>
<target name="war" depends="compile">
<war destfile="${dir.dist}/SoulVoxServer.war" needxmlfile="false">
<fileset dir="WebContent"/>
<lib dir="${dir.lib}"/>
<classes dir="${dir.classes}"/>
</war>
</target>
<target name="clean">
<delete dir="${dir.dist}" />
<delete dir="${dir.build}" />
</target>
I thought that the problem can depend on web.xml file missing, but i use annotation so it should work anyway, isn't it?
Thank you!
EDIT
I found that my war file doesnt contain any classes. Its structure:
+META-INF
--MANIFEST.MF
+WEB-INF
--classes (It is empty)
--lib (here goes my jar files. Its ok)
-Playlist.jsp
EDIT
I solved that problem and now i see the next:
I have 2 war files:
1) Generated by ant. 13.3 Mb. Doesnt work.
2) Generated by eclipse and has the same files inside (after jar -xvf), but it is only 6.6 Mb size.. Thi one works.
What is that?

Mysterious Ant script

I have problem with my Ant script. I have to run junit test on ant run.
My current script looks like:
<property name="src" location="src"/>
<property name="build" location="build"/>
<property name="doc" location="doc"/>
<property name="dist" location="dest"/>
<property name="lib" location="lib"/>
<property name="app" value="${ant.project.name}.jar"/>
<presetdef name="javac">
<javac includeantruntime="false"/>
</presetdef>
<target name="clean">
<delete dir="${build}"/>
<delete dir="${dist}"/>
</target>
<target name="compile" depends="clean" description="Compile">
<mkdir dir="${build}"/>
<javac srcdir="${src}"
destdir="${build}"
classpath="${lib}/junit-4.10.jar:${lib}/swing-layout-1.0.4.jar:${src}">
</javac>
<copy todir="${build}/checkers">
<fileset dir="${lib}">
<include name="resources/**" />
</fileset>
</copy>
</target>
<target name="run" depends="compile">
<echo>Running the junit tests...</echo>
<junit showoutput="no" fork="no">
<classpath>
<pathelement location="${build}"/>
<pathelement path="${build}:${lib}/junit-4.10.jar"/>
</classpath>
<formatter type="plain" usefile="false" />
<test name="checkers.CheckersTest"/>
</junit>
</target>
On my Linux box test runs fine and everything looks good. But on my Windows, Ant gives my nice:
java.lang.NoClassDefFoundError: junit/framework/TestListener
Ant in debug mode however told me that he loaded TestListener.class from suplied junit-4.10.jar file.
Try this answer http://youtrack.jetbrains.com/issue/TW-4882:
To fix the problem you should either use fork="true" attribute for
junit task (in this case classpath will be created correctly), or
to copy junit.jar to ANT_HOME/lib (to ensure correct class loading).
Here is also bug for this https://bugs.eclipse.org/bugs/show_bug.cgi?id=36198. Last comment says JUnit is available in Ant via the org.eclipse.ant.optional.junit fragment

Ant built does not generate class files

I'm using build.xml to build my src. However it failed to generate class files without any error message. The full script is
<?xml version="1.0"?>
<project name="auxiliary" basedir="." default="dist">
<property name="src.dir" value="../auxiliary-src/com/nextbio/drugbank"/>
<property name="dist.dir" value="dist"/>
<property name="lib.dir" value="../jboss_config/common_app_jars"/>
<property name="temp.dir" value="temp"/>
<property name="foo_dist.dir" value="../foo/dist"/>
<path id="libs-classpath">
<fileset dir="${foo_dist.dir}">
<include name="foo.jar"/>
</fileset>
</path>
<target name="dist" depends="auxiliary-dist" />
<target name="auxiliary-cleanup">
<delete dir="${temp.dir}"/>
<delete dir="${dist.dir}"/>
<echo message="cleaned up. ${temp.dir}, and ${dist.dir} have been deleted."/>
</target>
<target name ="auxiliary-dist">
<delete dir="${temp.dir}"/>
<echo message="delete ${temp.dir}" />
<mkdir dir="${temp.dir}"/>
<javac destdir="${temp.dir}" source="1.6" target="1.6" debug="on" fork="true" memorymaximumsize="1024m">
<src path="${src.dir}"/>
<classpath>
<path refid="libs-classpath"/>
</classpath>
<include name="com/car/**"/> <!-- troubled line -->
</javac>
<!--<copy overwrite="true" todir="${temp.dir}">
<fileset dir="${src.dir}">
<exclude name="**/*.java"/>
<exclude name="**/*.sql"/>
<exclude name="**/*.txt"/>
</fileset>
</copy>
<delete dir="${dist.dir}"/>
<mkdir dir="${dist.dir}"/>
<jar destfile="${dist.dir}/auxiliary.jar" basedir="${temp.dir}"/> -->
</target>
There is no class file in ${temp.dir} after this step, and no error message. I double checked it, and found it is because of the "troubled line". I tried to add some files to the classpath. I don't know why it is wrong.
The source path should point to the root of the package tree. You make it point to a specific package inside the sources : ../auxiliary-src/com/nextbio/drugbank.
And in the javac task, you ask it to compile all the files matching the pattern com/car/**. That means that it will compile the Java source files in ../auxiliary-src/com/nextbio/drugbank/com/car or in a subdirectory. If that's the case, you have very unconventional package names.
I had the same problem.
My project complilated well but the classes there weren't in nowhere and It didn't have any error message.
My problem was the classpath. The eclipse wizard added EclipseLink 2.5.1 jars.
I removed it and the problem is gone.
I suggest make a simple HelloWord and remove all jars
reference from the classpath and try again.
I encountered this "ant, javac, compile" problem related with the classpath to.
No debug or verbose message shown.
This behavior appear because in classpath exists not compatible (superior) version jar packages and that cause no output classes.

Making Java step in Ant script fail the build

Please excuse if the question is dumb, I'm only 2nd day on Ant and Java hacking together some CI solution with next to no knowledge of Ant or Java.
So I wish a build to fail if (my) java program run as a step within the build decides that the build must fail.
I thought of just throwing an unhandled exception in the Java program or using System.exit() to shut down the JVM but they seem quite nasty.
Is there a nice way of ant failing the build if a java step decides it should?
For the <java> task, there is an attribute failonerror. If you set it to yes (or true), the build will fail if the process returned anything else than 0.
The problem is that for returning some value from a java call, this call must System.exit(value). For it to not kill your ant, you also need to provide fork=true to run in a new JVM.
So, the java call could look like this:
<java jar="..."
fork="yes"
failonerror="yes">
</java>
Of course, you could also have your Java program implement the Ant Task API and load/call it as a proper ant task. Then it can itself decide what to do (and will be more configurable, too).
The Ant manual shows a built-in task named Fail which you can configure with specific conditions to make the build fail.
<fail message="Files are missing.">
<condition>
<not>
<resourcecount count="2">
<fileset id="fs" dir="." includes="one.txt,two.txt"/>
</resourcecount>
</not>
</condition>
</fail>
You might want to look into that one.
Ant ought to be straightforward. It does fail a build if a particular step does not succeed. I think the behavior you want is already built-in.
As for your custom step, my advice would be to find a way to do that outside of Ant for now while you get the rest of the CI flow working. Better to make that much progress rather than falling into a hole over one detail.
It might help if you describe what your program is doing. Perhaps there's a better way to accomplish what you need.
UPDATE: I don't think you should head down this path. The tests you run with CC should be unit tests. If you have to package and deploy the application to test, I'd call those integration tests. Run those separately as part of your QA step, not the build.
You're doing the right thing with Selenium; I like your rigor and effort. But I'd recommend running just the unit tests with CC, package and deploy the app to a QA server, then run your Selenium tests as JUnits. They're scripted and fast.
I also wonder about the wisdom of using Selenium to check for widget placements in the UI. That seems brittle to me; best left to a human.
Here's a generic Ant build that I re-use often. Feel free to use it as reference. Keep telling yourself "This ought to be simple." IF it gets too hard, you're doing it wrong.
<?xml version="1.0" encoding="UTF-8"?>
<project name="xslt-converter" basedir="." default="package">
<property name="version" value="1.6"/>
<property name="haltonfailure" value="no"/>
<property name="out" value="out"/>
<property name="production.src" value="src"/>
<property name="production.lib" value="lib"/>
<property name="production.resources" value="config"/>
<property name="production.classes" value="${out}/production/${ant.project.name}"/>
<property name="test.src" value="test"/>
<property name="test.lib" value="lib"/>
<property name="test.resources" value="config"/>
<property name="test.classes" value="${out}/test/${ant.project.name}"/>
<property name="exploded" value="out/exploded/${ant.project.name}"/>
<property name="exploded.classes" value="${exploded}/WEB-INF/classes"/>
<property name="exploded.lib" value="${exploded}/WEB-INF/lib"/>
<property name="reports.out" value="${out}/reports"/>
<property name="junit.out" value="${reports.out}/junit"/>
<property name="testng.out" value="${reports.out}/testng"/>
<path id="production.class.path">
<pathelement location="${production.classes}"/>
<pathelement location="${production.resources}"/>
<fileset dir="${production.lib}">
<include name="**/*.jar"/>
<exclude name="**/junit*.jar"/>
<exclude name="**/*test*.jar"/>
</fileset>
</path>
<path id="test.class.path">
<path refid="production.class.path"/>
<pathelement location="${test.classes}"/>
<pathelement location="${test.resources}"/>
<fileset dir="${test.lib}">
<include name="**/junit*.jar"/>
<include name="**/*test*.jar"/>
</fileset>
</path>
<path id="testng.class.path">
<fileset dir="${test.lib}">
<include name="**/testng*.jar"/>
</fileset>
</path>
<available file="${out}" property="outputExists"/>
<target name="clean" description="remove all generated artifacts" if="outputExists">
<delete dir="${out}" includeEmptyDirs="true"/>
<delete dir="${reports.out}" includeEmptyDirs="true"/>
</target>
<target name="create" description="create the output directories" unless="outputExists">
<mkdir dir="${production.classes}"/>
<mkdir dir="${test.classes}"/>
<mkdir dir="${reports.out}"/>
<mkdir dir="${junit.out}"/>
<mkdir dir="${testng.out}"/>
<mkdir dir="${exploded.classes}"/>
<mkdir dir="${exploded.lib}"/>
</target>
<target name="compile" description="compile all .java source files" depends="create">
<!-- Debug output
<property name="production.class.path" refid="production.class.path"/>
<echo message="${production.class.path}"/>
-->
<javac srcdir="src" destdir="${out}/production/${ant.project.name}" debug="on" source="${version}">
<classpath refid="production.class.path"/>
<include name="**/*.java"/>
<exclude name="**/*Test.java"/>
</javac>
<javac srcdir="${test.src}" destdir="${out}/test/${ant.project.name}" debug="on" source="${version}">
<classpath refid="test.class.path"/>
<include name="**/*Test.java"/>
</javac>
</target>
<target name="junit-test" description="run all junit tests" depends="compile">
<!-- Debug output
<property name="test.class.path" refid="test.class.path"/>
<echo message="${test.class.path}"/>
-->
<junit printsummary="yes" haltonfailure="${haltonfailure}">
<classpath refid="test.class.path"/>
<formatter type="xml"/>
<batchtest fork="yes" todir="${junit.out}">
<fileset dir="${test.src}">
<include name="**/*Test.java"/>
</fileset>
</batchtest>
</junit>
<junitreport todir="${junit.out}">
<fileset dir="${junit.out}">
<include name="TEST-*.xml"/>
</fileset>
<report todir="${junit.out}" format="frames"/>
</junitreport>
</target>
<taskdef resource="testngtasks" classpathref="testng.class.path"/>
<target name="testng-test" description="run all testng tests" depends="compile">
<!-- Debug output
<property name="test.class.path" refid="test.class.path"/>
<echo message="${test.class.path}"/>
-->
<testng classpathref="test.class.path" outputDir="${testng.out}" haltOnFailure="${haltonfailure}" verbose="2" parallel="methods" threadcount="50">
<classfileset dir="${out}/test/${ant.project.name}" includes="**/*.class"/>
</testng>
</target>
<target name="exploded" description="create exploded deployment" depends="testng-test">
<copy todir="${exploded.classes}">
<fileset dir="${production.classes}"/>
</copy>
<copy todir="${exploded.lib}">
<fileset dir="${production.lib}"/>
</copy>
</target>
<target name="package" description="create package file" depends="exploded">
<jar destfile="${out}/${ant.project.name}.jar" basedir="${production.classes}" includes="**/*.class"/>
</target>
</project>

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