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Java语言在添加带有参数的生成方法时,编译器抛出lang.AssertionError

  •  7
  • bramhaag  · 技术社区  · 7 年前

    我正在使用内部sun API修改现有类( com.sun.tools.javac )使用注释处理器。我能够生成并添加 MethodDecl 到a ClassDecl 使用以下代码:

    JCTree.JCClassDecl classDecl = ...
    JCTree.JCMethodDecl methodDecl = ...
    JCTree[] trees = new JCTree[classDecl.defs.length() + 1];
    trees[classDecl.defs.length()] = methodDecl;
    classDecl.defs = List.from(trees);
    

    在我尝试向方法声明中添加参数之前,这一切都很好。我使用以下代码生成一个新的 :

    Map<String, Class<?>> paramMap = ...
    List<JCVariableDecl> parameters = List.from(paramMap.entrySet().stream()
            .map(e -> treeMaker.VarDef(treeMaker.Modifiers(Flags.PARAMETER), elements.getName(e.getKey()), getType(e.getValue()), null))
            .toArray(JCVariableDecl[]::new));
    ...
    JCMethodDecl methodDecl = treeMaker.MethodDef(modifiers, methodName, returnType, genericParameters, parameters, throwables, methodBody, null);
    

    编译时,我得到以下堆栈跟踪:

    An exception has occurred in the compiler (9). Please file a bug against the Java compiler via the Java bug reporting page (http://bugreport.java.com) after checking the Bug Database (http://bugs.java.com) for duplicates. Include your program and the following diagnostic in your report. Thank you.
    java.lang.AssertionError
        at jdk.compiler/com.sun.tools.javac.util.Assert.error(Assert.java:155)
        at jdk.compiler/com.sun.tools.javac.util.Assert.check(Assert.java:46)
        at jdk.compiler/com.sun.tools.javac.util.Bits.incl(Bits.java:186)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.initParam(Flow.java:1931)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.visitMethodDef(Flow.java:1880)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:866)
        at jdk.compiler/com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:393)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.scan(Flow.java:1451)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.visitClassDef(Flow.java:1822)
        at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:774)
        at jdk.compiler/com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:393)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.scan(Flow.java:1451)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.analyzeTree(Flow.java:2521)
        at jdk.compiler/com.sun.tools.javac.comp.Flow$AssignAnalyzer.analyzeTree(Flow.java:2504)
        at jdk.compiler/com.sun.tools.javac.comp.Flow.analyzeTree(Flow.java:212)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1389)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1363)
        at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:959)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$doCall$0(JavacTaskImpl.java:100)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.handleExceptions(JavacTaskImpl.java:142)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:96)
        at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:90)
        at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:49)
        at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:36)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.delegateAndHandleErrors(NormalizingJavaCompiler.java:99)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:52)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:37)
        at org.gradle.api.internal.tasks.compile.CleaningJavaCompilerSupport.execute(CleaningJavaCompilerSupport.java:35)
        at org.gradle.api.internal.tasks.compile.CleaningJavaCompilerSupport.execute(CleaningJavaCompilerSupport.java:25)
        at org.gradle.api.tasks.compile.JavaCompile.performCompilation(JavaCompile.java:204)
        at org.gradle.api.tasks.compile.JavaCompile.compile(JavaCompile.java:189)
        at org.gradle.api.tasks.compile.JavaCompile.compile(JavaCompile.java:121)
        at jdk.internal.reflect.GeneratedMethodAccessor170.invoke(Unknown Source)
        at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.base/java.lang.reflect.Method.invoke(Method.java:564)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
        at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$IncrementalTaskAction.doExecute(DefaultTaskClassInfoStore.java:179)
        at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$StandardTaskAction.execute(DefaultTaskClassInfoStore.java:135)
        at org.gradle.api.internal.project.taskfactory.DefaultTaskClassInfoStore$StandardTaskAction.execute(DefaultTaskClassInfoStore.java:122)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:121)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:110)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:92)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:70)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:62)
        at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:97)
        at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:87)
        at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.run(DefaultTaskGraphExecuter.java:248)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:241)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:230)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.processTask(DefaultTaskPlanExecutor.java:123)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.access$200(DefaultTaskPlanExecutor.java:79)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:104)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker$1.execute(DefaultTaskPlanExecutor.java:98)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.execute(DefaultTaskExecutionPlan.java:625)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.executeWithTask(DefaultTaskExecutionPlan.java:580)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor$TaskExecutorWorker.run(DefaultTaskPlanExecutor.java:98)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:59)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:128)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
        at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:46)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
        at org.gradle.initialization.DefaultGradleLauncher$ExecuteTasks.run(DefaultGradleLauncher.java:314)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
        at org.gradle.initialization.DefaultGradleLauncher.runTasks(DefaultGradleLauncher.java:204)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:134)
        at org.gradle.initialization.DefaultGradleLauncher.executeTasks(DefaultGradleLauncher.java:109)
        at org.gradle.internal.invocation.GradleBuildController$1.call(GradleBuildController.java:78)
        at org.gradle.internal.invocation.GradleBuildController$1.call(GradleBuildController.java:75)
        at org.gradle.internal.work.DefaultWorkerLeaseService.withLocks(DefaultWorkerLeaseService.java:152)
        at org.gradle.internal.invocation.GradleBuildController.doBuild(GradleBuildController.java:100)
        at org.gradle.internal.invocation.GradleBuildController.run(GradleBuildController.java:75)
        at org.gradle.tooling.internal.provider.runner.BuildModelActionRunner.run(BuildModelActionRunner.java:53)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.tooling.internal.provider.ValidatingBuildActionRunner.run(ValidatingBuildActionRunner.java:32)
        at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner$1.run(RunAsBuildOperationBuildActionRunner.java:43)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:336)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:328)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:199)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:110)
        at org.gradle.launcher.exec.RunAsBuildOperationBuildActionRunner.run(RunAsBuildOperationBuildActionRunner.java:40)
        at org.gradle.tooling.internal.provider.SubscribableBuildActionRunner.run(SubscribableBuildActionRunner.java:51)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:47)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:30)
        at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:39)
        at org.gradle.launcher.exec.BuildTreeScopeBuildActionExecuter.execute(BuildTreeScopeBuildActionExecuter.java:25)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:80)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:53)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:57)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:32)
        at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:36)
        at org.gradle.tooling.internal.provider.GradleThreadBuildActionExecuter.execute(GradleThreadBuildActionExecuter.java:25)
        at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:43)
        at org.gradle.tooling.internal.provider.ParallelismConfigurationBuildActionExecuter.execute(ParallelismConfigurationBuildActionExecuter.java:29)
        at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:64)
        at org.gradle.tooling.internal.provider.StartParamsValidatingActionExecuter.execute(StartParamsValidatingActionExecuter.java:29)
        at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:59)
        at org.gradle.tooling.internal.provider.SessionFailureReportingActionExecuter.execute(SessionFailureReportingActionExecuter.java:44)
        at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:45)
        at org.gradle.tooling.internal.provider.SetupLoggingActionExecuter.execute(SetupLoggingActionExecuter.java:30)
        at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:37)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
        at org.gradle.util.Swapper.swap(Swapper.java:38)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:62)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:82)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
        at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:295)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
        at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
        at java.base/java.lang.Thread.run(Thread.java:844)
    

    当我将参数替换为 List.nil() 这就是为什么我认为问题与参数有关。

    以下代码引发异常:

    public void incl(int x) {
        Assert.check(currentState != BitsState.UNKNOWN);
        Assert.check(x >= 0); // <-- this line
        sizeTo((x >>> wordshift) + 1);
        bits[x >>> wordshift] = bits[x >>> wordshift] |
            (1 << (x & wordmask));
        currentState = BitsState.NORMAL;
    }
    

    visitMethodDef 调用(从 Flow 类别):

    //important part in method visitMethodDef
    for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) {
        JCVariableDecl def = l.head;
        scan(def);
        Assert.check((def.sym.flags() & PARAMETER) != 0, "Method parameter without PARAMETER flag");
        /*  If we are executing the code from Gen, then there can be
         *  synthetic or mandated variables, ignore them.
         */
        initParam(def);
    }
    

    initParam :

    protected void initParam(JCVariableDecl def) {
        inits.incl(def.sym.adr);
        uninits.excl(def.sym.adr);
    }
    

    如果我理解正确,参数 sym.adr 是(<);0.手动创建 Symbol 并设置 adr 字段设置为大于0的值不起作用。

    生成的代码( MethodDecl#toString )有效:

    public static java.lang.String test(java.lang.String arg) {
        System.out.println("Running test method!");
        return new java.lang.String("Hello!");
    }
    

    总之:A java.lang.AssertionError 编译带有参数的生成方法时抛出,我不确定如何修复它。

    6 回复  |  直到 7 年前
        1
  •  4
  •   DarkSeraphim    7 年前

    我通过创建一个MethodSymbol来获得生成的功能参数,并将其与TreeMaker::MethodDef(MethodSymbol,JCTree.JCBlock)一起使用来创建一个新的JCTree。JCMethodDecl,他们迭代参数以将其adr设置为0(这是可以接受的,并且@Piotr Wilkin提到的规范中没有任何内容让我相信这是无效的)。

    // maker is a TreeMaker instance
    // sym is a Symbol.MethodSymbol instance
    // body is a JCTree.JCBlock instance
    JCTree.JCMethodDecl decl = maker.MethodDef(sym, body);
    decl.params.forEach(p -> {
        p.sym.adr = 0;
    });
    

    我认为这之所以有效,是因为javac不会尝试创建新符号(因为已经存在一个符号),并且VarSymbols(JCTree.JCVariableDecl的sym字段)是可变的。此外,搜索javac代码几乎没有试图覆盖这一点。

        2
  •  3
  •   Piotr Wilkin    7 年前

    实际上 Symbol 课堂告诉你 adr 字段用于:

    The variable's address. Used for different purposes during flow analysis, translation and code generation. Flow analysis: If this is a blank final or local variable, its sequence number. Translation: If this is a private field, its access number. Code generation: If this is a local variable, its logical slot number.

    -1 ,基本上是与 null ,所以你得到的是语义上(虽然不是技术上)的 NullPointerException

        3
  •  2
  •   fashare2015    6 年前

    在阅读了javac的源代码之后,我终于找到了解决方案。

    sym.adr -1 ,然后由 newVar() :

    // Flow$AssignAnalyzer
    void newVar(JCVariableDecl varDecl) {
        ...
        sym.adr = nextadr;
    }
    

    但是 由调用 visitVarDef() 只有 tree.sym trackable :

    // Flow$AssignAnalyzer
    public void visitVarDef(JCVariableDecl tree) {
        ...
        boolean track = trackable(tree.sym);
        if (track && tree.sym.owner.kind == MTH) {
            newVar(tree);
        }
        ...
    }
    // Flow$AssignAnalyzer
    protected boolean trackable(VarSymbol sym) {
        return
            sym.pos >= startPos &&
            ((sym.owner.kind == MTH ||
            isFinalUninitializedField(sym)));
    }
    

    sym.pos >= startPos 在生成方法时为true。

    总之,我们应该设定 TreeMaker.pos TreeMaker.MethodDef() 这样地:

    // ensure the current pos is valid
    treeMaker.at(jcClassDecl.pos);
    
    treeMaker.MethodDef(...);
    
        4
  •  1
  •   Komarov Andrey    4 年前

    上述解决方案并没有解决我的问题。

    为了解决这个问题,我们需要使用 ,而不是 树匠。VarDef() . 以下是帮助我的解决方案:

    return treeMaker.MethodDef(
                modifiers,
                elementUtils.getName(methodName),
                treeMaker.Type(new Type.JCVoidType()),
                List.nil(),
                List.of(treeMaker.VarDef(treeMaker.Modifiers(0), paramName, treeMaker.Type(type), null)),
                List.nil(),
                body,
                null
        );
    

    工作解决方案:

    return treeMaker.MethodDef(
                    modifiers,
                    elementUtils.getName(methodName),
                    treeMaker.Type(new Type.JCVoidType()),
                    List.nil(),
                    List.of(treeMaker.Param(paramName, type, null)),
                    List.nil(),
                    body,
                    null
            );
    
        5
  •  1
  •   thelordvampire    4 年前

    我遵循了@fashare2015的理念。这是我的密码

    public static JCTree.JCMethodDecl createSetMethod(JCTree.JCVariableDecl field) {
        JCTree.JCFieldAccess thisX = TreeMaker.Select(TreeMaker.Ident(NameApi.fromString("this")), field.name);
        JCTree.JCAssign assign = TreeMaker.Assign(thisX, TreeMaker.Ident(field.name));
        JCTree.JCExpression methodType = TreeMaker.Type(new Type.JCVoidType());
        JCTree.JCBlock methodBody = TreeMaker.Block(0, List.of(TreeMaker.Exec(assign)));
        Name methodName = NameApi.fromString(StringUtils.generateMethodName("set", field.getName().toString()));
        JCTree.JCVariableDecl param = TreeMaker.VarDef(TreeMaker.Modifiers(Flags.PARAMETER), field.name, field.vartype, null);
        param.pos = field.pos; // <---- This lines I used
        
        return TreeMaker.MethodDef(TreeMaker.Modifiers(Flags.PUBLIC), methodName, methodType,
                List.nil(), List.of(param), List.nil(), methodBody, null);
    }
    

    我使用JDK版本14。

    你可以在这里拉我的演示: link

        6
  •  1
  •   Syscall - leaving SO... Juhzuri    4 年前

    我找到了解决方案

    在执行create getter方法之前,添加以下代码:

    treeMaker.pos = jcVariableDecl.pos; 
    

    例如:

    //add this code ,redefine the position of parameters in the syntax tree:
    
    treeMaker.pos = jcVariableDecl.pos;
    
    treeMaker.MethodDef(treeMaker.Modifiers(Flags.PUBLIC),
            getNewMethodName(jcVariableDecl.getName(), "set"),
            methodType,
            List.nil(),
            parameters,
            List.nil(),
            block,
            null);