Question

我在下面尝试代码......

@Grapes([
    @Grab('org.hsqldb:hsqldb:2.0.0'),
    @GrabConfig(systemClassLoader=true, initContextClassLoader=true)
])
import groovy.sql.Sql
println Class.forName('org.hsqldb.jdbc.JDBCDriver').newInstance()

它在groovyConsole中工作，但无法使用Web Start运行。以下是错误消息。

startup failed:
General error during conversion: No suitable ClassLoader found for grab

java.lang.RuntimeException: No suitable ClassLoader found for grab
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:513)
    at org.codehaus.groovy.reflection.CachedConstructor.invoke(CachedConstructor.java:77)
    at org.codehaus.groovy.runtime.callsite.ConstructorSite$ConstructorSiteNoUnwrapNoCoerce.callConstructor(ConstructorSite.java:102)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallConstructor(CallSiteArray.java:54)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:182)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:190)
    at groovy.grape.GrapeIvy.chooseClassLoader(GrapeIvy.groovy:173)
    at groovy.grape.GrapeIvy$chooseClassLoader.callCurrent(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallCurrent(CallSiteArray.java:46)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:133)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callCurrent(AbstractCallSite.java:141)
    at groovy.grape.GrapeIvy.grab(GrapeIvy.groovy:239)
    at groovy.grape.Grape.grab(Grape.java:141)
    at groovy.grape.GrabAnnotationTransformation.visit(GrabAnnotationTransformation.java:282)
    at org.codehaus.groovy.transform.ASTTransformationVisitor$3.call(ASTTransformationVisitor.java:302)
    at org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:839)
    at org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:544)
    at org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:520)
    at org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:497)
    at groovy.lang.GroovyClassLoader.doParseClass(GroovyClassLoader.java:306)
    at groovy.lang.GroovyClassLoader.parseClass(GroovyClassLoader.java:287)
    at groovy.lang.GroovyShell.parseClass(GroovyShell.java:731)
    at groovy.lang.GroovyShell.parse(GroovyShell.java:743)
    at groovy.lang.GroovyShell.parse(GroovyShell.java:698)
    at groovy.lang.GroovyShell.evaluate(GroovyShell.java:648)
    at groovy.lang.GroovyShell.evaluate(GroovyShell.java:636)
    at com.lyhdev.mrcode.ScriptLoader.loadGroovy(Unknown Source)
    at com.lyhdev.mrcode.ScriptLoader$loadGroovy.call(Unknown Source)
    at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:42)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
    at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
    at Script1.run(Script1.groovy:30)
    at groovy.lang.GroovyShell.evaluate(GroovyShell.java:650)
    at groovy.lang.GroovyShell.evaluate(GroovyShell.java:636)
    at com.lyhdev.mrcode.ScriptLoader.loadGroovy(Unknown Source)
    at com.lyhdev.mrcode.ScriptLoader.main(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.sun.javaws.Launcher.executeApplication(Launcher.java:1804)
    at com.sun.javaws.Launcher.executeMainClass(Launcher.java:1750)
    at com.sun.javaws.Launcher.doLaunchApp(Launcher.java:1512)
    at com.sun.javaws.Launcher.run(Launcher.java:130)
    at java.lang.Thread.run(Thread.java:662)

1 error

Answer 1

Dunno是否有帮助，但请看 http://www.randomactsofsentience.com/2012/01/that-darned-no-suitable-classloader.html 如果这有帮助。

Answer 2

所有涉及的类加载器都是如此。例如，我从ant运行groovy时遇到了同样的问题。我似乎因为在ant或web start下运行groovy时系统类加载器不是groovy类加载器或根加载器。请参阅GrapeIvy.groovy中的isValidTargetClassLoader（）。

问题的一个解决方案是确保你有一个groovy RootLoader，在你的脚本中添加所有必要的类路径，然后从你的groovy脚本/类运行你的应用程序。我猜想网络开始会很棘手。

转换期间的常规错误：没有找到适合抓取的ClassLoader

2 个答案: