in our web-app project, we include some jar files. For patching some issues of one of the classes in a jar file, we changed the implemention of this class in a patches source folder.
Since there is a defined class loading order in tomcat (WEB-INF/classes before WEB-INF/lib), the patched version of the class is loaded by tomcat, not the original one in the jar file. So, as soon as we deploy our application, everything works as expected.
Now, we want to run junit tests from ant against this patched class. So we configure the class path to hold both, the original jar and the patched class file. But there seems to be no way to tell the ant's junit task to first load the patched class, not the unpatched version from the jar file.
Is there a way to get around the problem? Is there a way to determine the order in which the classes are loaded by ant's junit task? Is there any other way to test our patched class from ant?
I think an ant classpath works just like the standard Java classpath. The classpath is searched in the order that paths are declared and a class is loaded from the first path where it is found.
Your classpath element for your junit task should be something like:
<classpath>
<pathelement location="${patched.class.folder}"/>
<pathelement location="${original.class.jar}"/>
</classpath>
Related
I could not find a proper answer to the following question : while creating an executable jar from groovy compiled sources, I cannot simply include groovy-all-version.jar in a lib directory (as I would do in java) but I need to extract all the classes from the jar and package them with my own classes as otherwise I get an exception. This actually is the case with all libraries I may want to use.
Not clear ? Let's see an example.
toto.groovy belonging to package titi is compiled in a build directory which looks like this :
build
lib
groovy-all-1.8.4.jar
titi
toto.class
and a MANIFEST.MF that will be included in the jar contains the lines:
Main-Class: titi.toto
Class-Path: lib/groovy-all-1.8.4.jar
Executable jar creation is done with the following ant target in build.xml:
<jar destfile="${build.exe.dir}/${exe.name}"
basedir="${build.dir}"
manifest="${src.conf.dir}/MANIFEST.MF"
/>
Now if I try to execute the jar, I get
$ java -jar target/toto.jar
Exception in thread "main" java.lang.NoClassDefFoundError: groovy/lang/Script
(I've checked that the groovy.lang.Script class exists.)
On the other hand, if I unjar groovy-all-version.jar in build by adding an unjar task before the jar, execution goes fine. OK, it works, but it slows down the compilation process and I'd like to understand...
Any feedback is highly appreciated.
I'm using a #Grab annotation to grab the definition of an Html parser I can give to the XMLSlurper (I think it's the tagsoup parser) and all is good when I run my script from the cmd line. If I invoke the same script from Ant I get an Ivy NoClassDefFound error. I think it may berelated to having Ivy in Antlib. Is there another way to parse Html without customizing the slurper via #Grab?
This:
#Grab(group='org.ccil.cowan.tagsoup', module='tagsoup', version='1.2' )
doc = new XmlSlurper(new org.ccil.cowan.tagsoup.Parser()).parse(confluenceWebPageInputStream)
Works just fine from the command line but when I run it from an Ant build target:
<target name="update-wiki-chart">
<echo message="Will update chart for version ${version}"/>
<java dir="${basedir}" classname="groovy.lang.GroovyShell">
<arg value="ParseWikiPage.groovy"/>
<classpath refid="groovylib"/>
</java>
</target>
where groovyLib is a path ref pointing to the Groovy-1.8.6 jar downloaded from our internal Nexus repo, I get the NoClassDefFound error. I'm thinking this is probably due to having Ivy installed in Antlib causing the class loader to find it in two places. I just thought of something while writing this post. I can probably run java in forked mode or do something to cause it to not see/share Ant's classpath.It's been a few years since I've wrestled w/ Ant and class loader issues. My project is a little delinquent due to the bug and I'm looking for a quick/easy fix.
I just tried running my groovy on the cmd line via the "java" cmd and loading groovy-all jar in the class path and I realized that I get the NoClassDefFound error there as well. It has nothing to do with collisions with Ivy under Antlib. Rather, I am missing Ivy altogether. I had assumed it was included in Groovy-all.jar. I just need a clever way of passing Ivy from AntLib into my java task to get this all up and running.
Sounds like you're missing one or more jars from the classpath. I'd suggest digging around the classpathref you've labelled "groovylib".
A less error prone way to launch groovy from within ANT using the groovy ANT task.
Here's a similar example to your use-case:
Parse HTML using with an Ant Script
My example uses ivy directly to manage all build dependencies. The Grab annotations are still supported but obviously these would only manage the dependencies of the groovy script.
I have multiple JavaFX 2.0 apps (built with the default ant scripts generated by netbeans 7.0) which I want to be wrapped up into a war by a maven pom in the parent directory.
The war-building pom has lots of ant tasks in the compile phase that look like this:
<ant antfile="FXapplication1/build.xml" target="jar"/>
But when I go to run 'mvn compile', I get this error from ant:
"C:\path\to\warbuilder\FXapplication1\nbproject\build-impl.xml:209: Must set src.dir"
The ant script builds fine when explicitly called inside its own directory, so I'm assuming that the problem is that it's looking in the war builder's local directory for its source files, rather than looking for them relative to the build.xml. Is there a way to specify a working path for a given ant task?
Try making the JavaFX apps modules of the warbuilder app, each with their own pom which executes <ant antfile="build.xml" target="jar"/>,
rather than running <ant antfile="FXapplication1/build.xml" target="jar"/> from the parent.
The parent should list the children as modules, they will then be executed as part of the parent build process.
I'm working with ant on linux using the command line. I've got a simple build step with javac. This compiles correctly but it creates a directory structure under build like my namespace.
ie: ./build/com/crosse/samplespace/SampleProgram.class
How can I get this output into one directory (where it's easier to call java on it).
I tried
<target name="output" depends="compile">
<copy todir="${output}">
<fileset dir="${build}" includes="**/*.class"/>
</copy>
</target>
but that repeats the same thing in my output directory. How can I use ant to get everything into a single directory?
Alternatively how could I use an ant step to copy another file into the root of that path (an apache commons configuration file)?
Edit: This is mainly a convenience factor, I get tired of navigating through the same 3 directories to run my program.
What about creating a jar file containing all your files (classes and other resources)?
A jar also has a 'default' class the main method of which gets executed when the user double clicks it or calls it using java -jar <jar-file>.
You can use the Ant jar task.
Beside that, it is important that you keep your directory structure (outside a jar), otherwise the java class loader won't be happy when it has to load these classes. Or did I get your question wrong?
To answer your question, you would use a flatten mapper, as carej points out. The copy task even has a shortcut for it:
<copy todir="${output}" flatten="yes">
<fileset dir="${build}" includes="**/*.class"/>
</copy>
However, I also don't understand what you hope to accomplish with this. The java runtime expects class files to be in a directory structure that mirrors the package structure. Copying the class files to the top-level directory won't work, unless the classes are in the default package (there is no package statement in the .java files).
If you want to avoid having to manually change directories, you can always add a target to your ant build file that calls the java task with the appropriate classpath and other parameters. For example:
<target name="run" depends="compile">
<java classname="com.crosse.samplespace.SampleProgram"
classpath=".:build"/>
</target>
You can accomplish what you want to do by using the flattenmapper but I'm at a loss to understand what possible valid reason you'd have for doing it.
I want to use the FTP task in ant, and I have found the appropriate jar files and got everything working fine. I have put the jar files in a "libs" directory alongside the other files used in the build. The only problem is that the user must run "ant -lib commons-net-ftp-2.0.jar" to make a build; I would really prefer that it were possible to just run "ant" with no arguments.
Reading the ant optional tasks intallation page, I see that there are five ways one can load up extra libraries in ant, and none of them are really what I'm looking for. I do not want to force the user to make any modifications to their system to run this task; it should be possible to just load it from the "libs" directory inside of our product's source folder. So that means setting the global CLASSPATH is also out (which is a bad idea anyways).
The last option, as noted in the documentation, is the preferred approach... loading the jarfiles individually from the build script itself. I have done this in the past with the ant-contrib tasks and JUnit, and would like to do that here, but I don't see how I can accomplish this. The FTP task doesn't support a nested classpath element, and I don't know the XML resource I would need to load this library via a taskdef. How can I load the libraries from within ant?
Edit: In response to the answers and questions which have been posted here so far, I'm using ant 1.7.1. Making an ftp taskdef definitely does not work; that throws the following error:
BUILD FAILED
/my/path/build.xml:13: taskdef class org.apache.tools.ant.taskdefs.optional.net.FTP cannot be found
Perhaps this is because the classname is wrong. How exactly do I find the classname I'm supposed to use if I only have a jarfile? It's not documented anywhere, and I couldn't find anything in the jar itself resembling that path.
The problem you are having is due to the different class-loaders in use. The Commons Net classes must be loaded by the same class-loader that loads the FTP task. Because the FTP task is loaded by Ant on start-up, you need to add the Commons Net to Ant's classpath so that it is loaded by the same class-loader. That's why the documentation gives you 4 different ways to do this.
I agree that none of them are ideal (the CLASSPATH environment variable being the worst). One way around this is to supply a shell script with your project that invokes Ant and passes the apporpriate -lib argument. You then get people to use this rather than invoking Ant directly. In fact, you could deviously name it 'ant' so that it gets run instead of the existing 'ant' on the path (this only works if the current directory is on the path, ahead of other directories).
The fifth option in the documentation is great in theory. They finally fixed the class-loading problems in 1.7.0. Unfortunately, as you mention, nobody retro-fitted the FTP task to take a classpath. You could try submitting an enhancement request, but this won't help in the short term.
There is one other option, which isn't any better than the others. Instead of making sure that the Commons Net classes are loaded by the class-loader that loads the FTP task, you could make sure that the FTP task is loaded by the class-loader that loads the Commons Net classes. To do this you have to remove the ant-commons-lib.jar file from the 'lib' directory of the Ant installation. This means that the FTP task won't get loaded on start-up. This is actually why the optional tasks are broken up into so many separate JARs - so that they can be individually removed. Put this JAR file alongside the Commons Net JAR file so that it can be loaded at the same time. Then you can do something like this (I tried this and it works):
<taskdef name="ftp"
classname="org.apache.tools.ant.taskdefs.optional.net.FTP">
<classpath>
<pathelement location="${basedir}/lib/ant-commons-net.jar"/>
<pathelement location="${basedir}/lib/commons-net-2.0.jar"/>
</classpath>
</taskdef>
<ftp server="yourserver.com"
userid="anonymous"
password="blah">
<fileset dir="somedirectory"/>
</ftp>
But this is probably a worse option than just using the -lib switch (with or without a wrapper script). The only other thing I can think of is to try to find a third-party FTP task to use instead of the default one.
I have a solution:
you can download a new "classloader" task from http://enitsys.sourceforge.net/ant-classloadertask/ and load it whith:
<taskdef resource="net/jtools/classloadertask/antlib.xml"
classpath="XXX/ant-classloadertask.jar"/>
Naw can do things like loading classes with the same classloader that ant use for his task:
<classloader loader="system" classpath="XXX/commons-net-2.0.jar"/>
or "loader="project""
Then you definde your task:
<taskdef name="ftp" classname="org.apache.tools.ant.taskdefs.optional.net.FTP"/>
and go :-)
So I succeeded in doing this for the ant-salesforce.jar that you get when trying to do salesforce work (fun...)
Check to see if the jar has an xml file in it that looks something like this:
<antlib>
<typedef name="compileAndTest" classname="com.salesforce.ant.CompileAndTest"/>
....
</antlib>
Then in ant give it a taskdev that reads that file from inside the given jar, like this:
<taskdef resource="com/salesforce/antlib.xml" classpath="lib/ant-salesforce.jar" />
Hope that helps some.
Ah, man, this is just so nasty. I run ant from eclipse. I don't want to reconfigure ant in eclipse for new workspaces, so here's what I decided to do, to decouple running the task and configuring ant. I extracted the ftp task to a separate build file. Next I added a native call to the command line to start a completely new ant process with the required libraries on the path:
<target name="deploy-ftp">
<exec command="ant">
<arg line="-buildfile ftp.xml deploy-ftp -lib lib/ant"/>
</exec>
</target>
Now the master build file can be run without any special arguments and no modifications are required to the ant installation. It's nasty though, since the ftp task runs in a completely clean environment. None of the properties and paths from the master build file are available. Luckily I had all of these in a separate property file anyway, so I only needed a single import.
I would like to add a big thanks to Dan Dyer. Without your extensive explanation of what's going on behind the scenes, I wouldn't have found this solution.
Will this work assuming libs is directly under you project's base directory
<taskdef name="ftp" classname="org.apache.tools.ant.taskdefs.optional.net.FTP">
<classpath>
<pathelement location="${basedir}\libs\commons-net-1.4.0.jar"/>
</classpath>
</taskdef>
Your users all have ant installed on their machines but you can't / don't want to make them add the FTP jar? Can you bundle ant with your project make tasks that call YOUR ant bundle, with the jars placed so it'll work as follows?
<taskdef name="ftp" classname="org.apache.tools.ant.taskdefs.optional.net.FTP">
<classpath>
<pathelement location="\lib\commons-net-1.4.0.jar"/>
</classpath>
</taskdef>
<target name="testFtp">
<ftp server="blah" userid="foo" password="bar">
<fileset file="test.file" />
</ftp>
</target>