Re: Maven debugging HOWTO
Jochen, thank you for this. I tried with embedder(didn't work), so this will really help me. On 12/23/05, Jochen Wiedmann [EMAIL PROTECTED] wrote: Hi, it took me some time to figure this out, so it seems worth sharing. Jochen -- Often it does seem a pity that Noah and his party did not miss the boat. (Mark Twain) Maven Debugging HOWTO === When looking for bugs in Maven itself or plugins, it saves a real lot of time, if you can run Maven in a debugger. Fortunately, this is a relatively trivial task, if you know what to do. 1.) Invoking Maven from the command line Basically, your debugger should execute the following command line. M2_HOME=/usr/local/maven-2.0.1 # Or whatever you have as Maven home # use set M2_HOME=... on Windows M2_REPO=/home/jochen/.m2/repository # Or whatever you have as Maven repository # use set M2_REPO=... on Windows CW=$M2_REPO/classworlds/classworlds/1.1-alpha-2/classworlds- 1.1-alpha-2.jar # The version number may depend on the Maven version. # Check your mvn script, if you are in doubt. # Use set CW=%M2_REPO%/... on Windows ARGS=-Dclassworlds.conf=$M2_HOME/bin/m2.conf -Dmaven.home=$M2_HOME # Use set ARGS=-Dclassworlds.conf=%M2_HOME%/... on Windows java -cp $CW $ARGS org.codehaus.classworlds.Launcher goals # Use java -cp %CW% ... on Windows 2.) Using an IDE Basically, it should be easy to translate the above command line into your IDE's settings. In what follows, I'll describe the Eclipse IDE as an example. However, there's one imortant Gotcha, which you should be aware of: In the above example, the initial classpath contains the classworlds jar file - and nothing else! Your IDE will typically suggest a larger classpath. For example, if you have a Maven project, it will suggest to put this project and its dependencies on the classpath. But that will most likely fail. The reason is, that the projects dependencies will typically contain multiple instances of the same dependency. For example, with Maven 2.0.1 you will have plexus-utils 1.0.4 as well as plexus-utils-1.0.5. This is no problem, if you are using the class loaders that Maven creates for you. It won't work, if the IDE creates class loaders: For example, depending on the order of dependencies, only version 1.0.4 will be used, even if some classes depend on 1.0.5. In other words: Before starting the IDE's debugger, make sure that the class path contains the boot class loader and the classworlds.jar file, but nothing else. 3.) Example: The Eclipse IDE --- - Make sure, that the Maven 2 Eclipse Plugin is installed. See http://maven.apache.org/eclipse-plugin.html for installing the plugin. - Checkout the following projects from SVN. Maven: http://svn.apache.org/repos/asf/maven/components/tags/maven-2.0.1/ If you need plugin parents, checkout other projects as well, for example Plugins: http://svn.apache.org/repos/asf/maven/plugins/trunk Note, that I did *not* checkout the Maven trunk. That rarely pays. Typically, you'll find differences in the plugin versions which are being used. Unfortunately, tags like Maven 2.0.1 are valid for the Maven core only. There are no such tags for the various plugins. This makes it sometimes rather difficult to have the right plugin sources. (Hint to the Maven developers!) - Use the Maven 2 plugin to enable that these projects are Maven projects. - Initially, invoke the bootstrap script in the Maven root directory. - Select Run/Run... in the menu. A window opens. - Select Java Application and press the New button. - Set the new debugging profiles name, for example Maven. - Enter the Main class: org.codehaus.classworlds.Launcher Do not attempt to use the Search button: It doesn't show main classes in dependencies. - Switch to Arguments. - In Program arguments, enter the goals you want to use, plus properties you want to set. - In VM arguments, enter the -Dclassworlds.conf=... -Dmaven.home=... arguments from 1.) - Select Working directory/Other, and your projects base directory. (Where you would typically invoke mvn from.) - Switch to Classpath - Remove all User Entries. In particular, remove your project, and the Maven projects, if they should be there. - Add the classworlds jar file from 1.) to User Entries. - Switch to Source Path. - You may safely add your own projects, the Maven projects, plugin projects, and whatever you like, here. That's it. Press Run and watch Maven running. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: Maven debugging HOWTO
There's a easiest (I think) way using remote debugging export MAVEN_OPTS=-Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=5005 and in eclipse run - debug - new - remote java application port is the 5005 specified before Then you run mvn and hit debug in eclipse If somebody creates a document and open an issue this can be added to the docs Regards On 12/23/05, Jochen Wiedmann [EMAIL PROTECTED] wrote: Hi, it took me some time to figure this out, so it seems worth sharing. Jochen -- Often it does seem a pity that Noah and his party did not miss the boat. (Mark Twain) Maven Debugging HOWTO === When looking for bugs in Maven itself or plugins, it saves a real lot of time, if you can run Maven in a debugger. Fortunately, this is a relatively trivial task, if you know what to do. 1.) Invoking Maven from the command line Basically, your debugger should execute the following command line. M2_HOME=/usr/local/maven-2.0.1 # Or whatever you have as Maven home # use set M2_HOME=... on Windows M2_REPO=/home/jochen/.m2/repository # Or whatever you have as Maven repository # use set M2_REPO=... on Windows CW=$M2_REPO/classworlds/classworlds/1.1-alpha-2/classworlds- 1.1-alpha-2.jar # The version number may depend on the Maven version. # Check your mvn script, if you are in doubt. # Use set CW=%M2_REPO%/... on Windows ARGS=-Dclassworlds.conf=$M2_HOME/bin/m2.conf -Dmaven.home=$M2_HOME # Use set ARGS=-Dclassworlds.conf=%M2_HOME%/... on Windows java -cp $CW $ARGS org.codehaus.classworlds.Launcher goals # Use java -cp %CW% ... on Windows 2.) Using an IDE Basically, it should be easy to translate the above command line into your IDE's settings. In what follows, I'll describe the Eclipse IDE as an example. However, there's one imortant Gotcha, which you should be aware of: In the above example, the initial classpath contains the classworlds jar file - and nothing else! Your IDE will typically suggest a larger classpath. For example, if you have a Maven project, it will suggest to put this project and its dependencies on the classpath. But that will most likely fail. The reason is, that the projects dependencies will typically contain multiple instances of the same dependency. For example, with Maven 2.0.1 you will have plexus-utils 1.0.4 as well as plexus-utils-1.0.5. This is no problem, if you are using the class loaders that Maven creates for you. It won't work, if the IDE creates class loaders: For example, depending on the order of dependencies, only version 1.0.4 will be used, even if some classes depend on 1.0.5. In other words: Before starting the IDE's debugger, make sure that the class path contains the boot class loader and the classworlds.jar file, but nothing else. 3.) Example: The Eclipse IDE --- - Make sure, that the Maven 2 Eclipse Plugin is installed. See http://maven.apache.org/eclipse-plugin.html for installing the plugin. - Checkout the following projects from SVN. Maven: http://svn.apache.org/repos/asf/maven/components/tags/maven-2.0.1/ If you need plugin parents, checkout other projects as well, for example Plugins: http://svn.apache.org/repos/asf/maven/plugins/trunk Note, that I did *not* checkout the Maven trunk. That rarely pays. Typically, you'll find differences in the plugin versions which are being used. Unfortunately, tags like Maven 2.0.1 are valid for the Maven core only. There are no such tags for the various plugins. This makes it sometimes rather difficult to have the right plugin sources. (Hint to the Maven developers!) - Use the Maven 2 plugin to enable that these projects are Maven projects. - Initially, invoke the bootstrap script in the Maven root directory. - Select Run/Run... in the menu. A window opens. - Select Java Application and press the New button. - Set the new debugging profiles name, for example Maven. - Enter the Main class: org.codehaus.classworlds.Launcher Do not attempt to use the Search button: It doesn't show main classes in dependencies. - Switch to Arguments. - In Program arguments, enter the goals you want to use, plus properties you want to set. - In VM arguments, enter the -Dclassworlds.conf=... -Dmaven.home=... arguments from 1.) - Select Working directory/Other, and your projects base directory. (Where you would typically invoke mvn from.) - Switch to Classpath - Remove all User Entries. In particular, remove your project, and the Maven projects, if they should be there. - Add the classworlds jar file from 1.) to User Entries. - Switch to Source Path. - You may safely add your own projects, the Maven projects, plugin projects, and whatever you like, here. That's it. Press
Maven debugging HOWTO
Hi, it took me some time to figure this out, so it seems worth sharing. Jochen -- Often it does seem a pity that Noah and his party did not miss the boat. (Mark Twain) Maven Debugging HOWTO === When looking for bugs in Maven itself or plugins, it saves a real lot of time, if you can run Maven in a debugger. Fortunately, this is a relatively trivial task, if you know what to do. 1.) Invoking Maven from the command line Basically, your debugger should execute the following command line. M2_HOME=/usr/local/maven-2.0.1 # Or whatever you have as Maven home # use set M2_HOME=... on Windows M2_REPO=/home/jochen/.m2/repository # Or whatever you have as Maven repository # use set M2_REPO=... on Windows CW=$M2_REPO/classworlds/classworlds/1.1-alpha-2/classworlds- 1.1-alpha-2.jar # The version number may depend on the Maven version. # Check your mvn script, if you are in doubt. # Use set CW=%M2_REPO%/... on Windows ARGS=-Dclassworlds.conf=$M2_HOME/bin/m2.conf -Dmaven.home=$M2_HOME # Use set ARGS=-Dclassworlds.conf=%M2_HOME%/... on Windows java -cp $CW $ARGS org.codehaus.classworlds.Launcher goals # Use java -cp %CW% ... on Windows 2.) Using an IDE Basically, it should be easy to translate the above command line into your IDE's settings. In what follows, I'll describe the Eclipse IDE as an example. However, there's one imortant Gotcha, which you should be aware of: In the above example, the initial classpath contains the classworlds jar file - and nothing else! Your IDE will typically suggest a larger classpath. For example, if you have a Maven project, it will suggest to put this project and its dependencies on the classpath. But that will most likely fail. The reason is, that the projects dependencies will typically contain multiple instances of the same dependency. For example, with Maven 2.0.1 you will have plexus-utils 1.0.4 as well as plexus-utils-1.0.5. This is no problem, if you are using the class loaders that Maven creates for you. It won't work, if the IDE creates class loaders: For example, depending on the order of dependencies, only version 1.0.4 will be used, even if some classes depend on 1.0.5. In other words: Before starting the IDE's debugger, make sure that the class path contains the boot class loader and the classworlds.jar file, but nothing else. 3.) Example: The Eclipse IDE --- - Make sure, that the Maven 2 Eclipse Plugin is installed. See http://maven.apache.org/eclipse-plugin.html for installing the plugin. - Checkout the following projects from SVN. Maven: http://svn.apache.org/repos/asf/maven/components/tags/maven-2.0.1/ If you need plugin parents, checkout other projects as well, for example Plugins: http://svn.apache.org/repos/asf/maven/plugins/trunk Note, that I did *not* checkout the Maven trunk. That rarely pays. Typically, you'll find differences in the plugin versions which are being used. Unfortunately, tags like Maven 2.0.1 are valid for the Maven core only. There are no such tags for the various plugins. This makes it sometimes rather difficult to have the right plugin sources. (Hint to the Maven developers!) - Use the Maven 2 plugin to enable that these projects are Maven projects. - Initially, invoke the bootstrap script in the Maven root directory. - Select Run/Run... in the menu. A window opens. - Select Java Application and press the New button. - Set the new debugging profiles name, for example Maven. - Enter the Main class: org.codehaus.classworlds.Launcher Do not attempt to use the Search button: It doesn't show main classes in dependencies. - Switch to Arguments. - In Program arguments, enter the goals you want to use, plus properties you want to set. - In VM arguments, enter the -Dclassworlds.conf=... -Dmaven.home=... arguments from 1.) - Select Working directory/Other, and your projects base directory. (Where you would typically invoke mvn from.) - Switch to Classpath - Remove all User Entries. In particular, remove your project, and the Maven projects, if they should be there. - Add the classworlds jar file from 1.) to User Entries. - Switch to Source Path. - You may safely add your own projects, the Maven projects, plugin projects, and whatever you like, here. That's it. Press Run and watch Maven running. - To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
