Debugging Grails Apps in Eclipse

This is pretty simple to accomplish. Simply run "grails-debug run-app" instead of "grails run-app".

However, be sure to start the debugger in Eclipse! The app doesn't finish starting up until the debugger is attached. I spent some time wondering what was taking so long before putting that together.

Grails LinkageError for SAXParseException

I ran "grails run-app" for the app that I've been working on and was greeted with the following :

java.lang.LinkageError: loader constraint violation: loader (instance of <bootlo
ader>) previously initiated loading for a different type with name "org/xml/sax/
SAXParseException"
   at java.lang.Class.getDeclaredMethods0(Native Method)
   at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
   at java.lang.Class.getDeclaredMethods(Class.java:1791)
   at java.security.AccessController.doPrivileged(Native Method)
   at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:4
6)
   at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:33)
   at grails.util.PluginBuildSettings.getPluginInfos(PluginBuildSettings.gr
oovy:127)
   at grails.util.PluginBuildSettings.getPluginInfos(PluginBuildSettings.gr
oovy)
   at grails.util.PluginBuildSettings$getPluginInfos.callCurrent(Unknown So
urce)
   at grails.util.PluginBuildSettings.getPluginInfo(PluginBuildSettings.gro
ovy:164)
   at grails.util.PluginBuildSettings$getPluginInfo.callCurrent(Unknown Sou
rce)
   at grails.util.PluginBuildSettings.getPluginInfoForSource(PluginBuildSet
tings.groovy:202)
   at org.codehaus.groovy.transform.ASTTransformationVisitor$3.call(ASTTran
sformationVisitor.java:303)
   at org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(Compil
ationUnit.java:832)
   at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(Compilat
ionUnit.java:519)
   at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(Co
mpilationUnit.java:495)
   at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.j
ava:472)
   at _GrailsEvents_groovy.run(_GrailsEvents_groovy:54)
   at _GrailsEvents_groovy$run.call(Unknown Source)
   at _GrailsClean_groovy$run.call(Unknown Source)
   at _GrailsClean_groovy.run(_GrailsClean_groovy:29)
   at _GrailsClean_groovy$run.call(Unknown Source)
$
   at _GrailsPlugins_groovy.run(_GrailsPlugins_groovy:32)
   at _GrailsPlugins_groovy$run.call(Unknown Source)
   at _GrailsRun_groovy$run.call(Unknown Source)
   at _GrailsRun_groovy.run(_GrailsRun_groovy:31)
   at _GrailsRun_groovy$run.call(Unknown Source)
   at RunApp.run(RunApp.groovy:25)
   at RunApp$run.call(Unknown Source)
   at gant.Gant.prepareTargets(Gant.groovy:606)
Error loading event script from file [PATH_TO_GRAILS\.grails
\1.3.1\projects\PROJECT_NAME\plugins\code-coverage-1.1.8\scripts\_Events.gr
oovy] loader constraint violation: loader (instance of <bootloader>) previously
initiated loading for a different type with name "org/xml/sax/SAXParseException"

Grails had done some sort of update that I didn't pay a lot of attention to. I wondered if this had something to do with the update and will have to find out what went on later.

I found an entry on the Grails Jira dealing with the problem of xerces and Java 6. The suggested solution was to remove xml-apis-1.0.2.b2.jar.

I ran :

find . -name "*xml*"
find . -name "*api*"

from my project directory, my .grails directory and my .ivy directory. I found xml-apis-1.3.04.jar in my .ivy directory.

I ran jarscan against my project directory, .grails directory and .ivy directory and found 0 hits for SAXParseException.

I added :

    inherits("global") {
      excludes "xml-apis"
  }

To my BuildConfig.groovy file just below dependencies. The app ran.

groovy.lang.MissingMethodException: No signature of method: static .list() is applicable for argument types:

I've started using Grails recently. Its really nice. Productive, easy to get up and running, etc.

My first stab at testing a Controller produced :

groovy.lang.MissingMethodException: No signature of method: static dbtestapp.Team.list() is applicable for argument types:
(org.codehaus.groovy.grails.web.taglib.GroovyPageAttributes) values: [[max:10]]
Possible solutions: is(java.lang.Object), wait(), wait(long), print(java.lang.Object), split(groovy.lang.Closure), use([Ljava.lang.Object;)
at dbtestapp.TeamController$_closure2.doCall

A little weird. list() is a dynamic method and should be on the object.

Its a known issue in the Grails Jira. The solution is to stick the test inside the "integration" package.