Play 1.2.5.4 上的 LocalvariablesNamesEnhancer 异常 - 我该如何调试（或解决它）？

Posted 2023-04-14

【中文标题】Play 1.2.5.4 上的 LocalvariablesNamesEnhancer 异常 - 我该如何调试（或解决它）？

【英文标题】：LocalvariablesNamesEnhancer exception on Play 1.2.5.4 - How can I debug this (or workaround it)?

【发布时间】：2015-07-30 12:59:15

【问题描述】：

我有一个控制器，它接收异步生成 CSV 的请求，这给了我一个异常：

Oops: UnexpectedException
An unexpected error occured caused by exception UnexpectedException: 
While applying class play.classloading.enhancers.LocalvariablesNamesEnhancer on
 controllers.Productions

我已设法将问题缩小到等待行。如果我删除它，我不会得到例外。谁能帮助我如何进一步调试问题或提出解决方法？

生产控制器：

@Check("user")
public static void exportz(int iDisplayStart, int sEcho, String sSearch,
 String searchFields) 
    ObjectType ztype = ObjectType.get(getControllerClass());


    Triple<String,String,String> triplet = parseListJSON(iDisplayStart, sEcho, sSearch, searchFields);
    String where = triplet.getLeft();
    String orderField = triplet.getMiddle();
    String orderDir = triplet.getRight();

    ExportCSV csvGen = new ExportCSV( ztype,  where, orderField,orderDir,sSearch,searchFields);
    response.contentType = "text/csv";
    do 
        Promise<String> csvGeneration =csvGen.now();
        String someCsvData =  await(csvGeneration);
        response.writeChunk(someCsvData);
    while(csvGen.moreData());

例外：

Oops: UnexpectedException
An unexpected error occured caused by exception UnexpectedException: While applying class play.classloading.enhancers.LocalvariablesNamesEnhancer on controllers.Productions
play.exceptions.UnexpectedException: While applying play.CorePlugin@7e6b9547 on controllers.Productions
    at play.plugins.PluginCollection.enhance(PluginCollection.java:556)
    at play.classloading.ApplicationClasses$ApplicationClass.enhance(ApplicationClasses.java:235)
    at play.classloading.ApplicationClassloader.loadApplicationClass(ApplicationClassloader.java:167)
    at play.classloading.ApplicationClassloader.getAllClasses(ApplicationClassloader.java:431)
    at play.Play.preCompile(Play.java:593)
    at play.Play.init(Play.java:299)
    at play.server.Server.main(Server.java:159)
Caused by: play.exceptions.UnexpectedException: While applying class play.classloading.enhancers.LocalvariablesNamesEnhancer on controllers.Productions
    at play.CorePlugin.enhance(CorePlugin.java:302)
    at play.plugins.PluginCollection.enhance(PluginCollection.java:551)
    ... 6 more
Caused by: javassist.CannotCompileException: by javassist.bytecode.BadBytecode: invalid opcode address
    at javassist.CtBehavior.insertAfter(CtBehavior.java:777)
    at play.classloading.enhancers.LocalvariablesNamesEnhancer.enhanceThisClass(LocalvariablesNamesEnhancer.java:269)
    at play.CorePlugin.enhance(CorePlugin.java:297)
    ... 7 more
Caused by: javassist.bytecode.BadBytecode: invalid opcode address
    at javassist.bytecode.CodeIterator.nextOpcode(CodeIterator.java:586)
    at javassist.bytecode.CodeIterator.next(CodeIterator.java:157)
    at javassist.bytecode.stackmap.Liveness.analyze(Liveness.java:237)
    at javassist.bytecode.stackmap.Liveness.computeUsage(Liveness.java:216)
    at javassist.bytecode.stackmap.Liveness.compute(Liveness.java:38)
    at javassist.bytecode.stackmap.TypedBlock.makeBlocks(TypedBlock.java:54)
    at javassist.bytecode.stackmap.MapMaker.make(MapMaker.java:91)
    at javassist.bytecode.MethodInfo.rebuildStackMap(MethodInfo.java:404)
    at javassist.bytecode.MethodInfo.rebuildStackMapIf6(MethodInfo.java:389)
    at javassist.CtBehavior.insertAfter(CtBehavior.java:768)
    ... 9 more

【参考方案1】：

好吧，我解决了将方法更改为新控制器的问题。我认为 LocalvariablesNamesEnhancer 有可能永远无法解决的 PlayFramework 上最古老的错误之一。

【讨论】：

我最终解决了这个问题，方法是将我想添加的代码移动到一个私有方法中并改为调用它。但即使这样也不是 100% 有效。我的实际建议是尽快离开 Play 1.x。