JDK-8073698 : NullPointerException Trying to Compile Code
  • Type: Bug
  • Component: tools
  • Sub-Component: javac
  • Affected Version: 8u31
  • Priority: P4
  • Status: Closed
  • Resolution: Duplicate
  • OS: windows_7
  • CPU: x86_64
  • Submitted: 2015-02-20
  • Updated: 2015-02-24
  • Resolved: 2015-02-24
Related Reports
Duplicate :  
JDK-8041713 - Type inference of non-existent method references crashes the compiler
Description
FULL PRODUCT VERSION :
java version "1.8.0_31"
Java(TM) SE Runtime Environment (build 1.8.0_31-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.31-b07, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

EXTRA RELEVANT SYSTEM CONFIGURATION :
None that I am aware of.

A DESCRIPTION OF THE PROBLEM :
When trying to compile a class using lambda expressions, the javac throws a null pointer exception with detailed stack trace.

ADDITIONAL REGRESSION INFORMATION: 
It has not worked on prior releases of java 8.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
javac JavacError.java

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I would expect class to compile
ACTUAL -
Null pointer exception

ERROR MESSAGES/STACK TRACES THAT OCCUR :
An exception has occurred in the compiler (1.8.0_31). Please file a bug at the Java Developer Connection (http://java.sun.com/webapps/bugreport)  after checking the Bug Parade for duplicates. Include your program and the following diagnostic in your report.  Thank you.
java.lang.NullPointerException
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitIdent(Flow.java:2380)
        at com.sun.tools.javac.tree.JCTree$JCIdent.accept(JCTree.java:2011)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
        at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:398)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1376)
        at com.sun.tools.javac.tree.TreeScanner.visitReference(TreeScanner.java:268)
        at com.sun.tools.javac.tree.JCTree$JCMemberReference.accept(JCTree.java:1973)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
        at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:398)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1376)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scanExpr(Flow.java:1627)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scanExprs(Flow.java:1639)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitApply(Flow.java:2236)
        at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
        at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:398)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1376)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.analyzeTree(Flow.java:2423)
        at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.analyzeTree(Flow.java:2406)
        at com.sun.tools.javac.comp.Flow.analyzeLambdaThrownTypes(Flow.java:250)
        at com.sun.tools.javac.comp.Attr.visitLambda(Attr.java:2423)
        at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.DeferredAttr$2.complete(DeferredAttr.java:284)
        at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:245)
        at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:232)
        at com.sun.tools.javac.comp.Resolve$MethodResultInfo.check(Resolve.java:993)
        at com.sun.tools.javac.comp.Resolve$4.checkArg(Resolve.java:826)
        at com.sun.tools.javac.comp.Resolve$AbstractMethodCheck.argumentsAcceptable(Resolve.java:731)
        at com.sun.tools.javac.comp.Resolve$4.argumentsAcceptable(Resolve.java:835)
        at com.sun.tools.javac.comp.Infer.instantiateMethod(Infer.java:162)
        at com.sun.tools.javac.comp.Resolve.rawInstantiate(Resolve.java:564)
        at com.sun.tools.javac.comp.Resolve.checkMethod(Resolve.java:601)
        at com.sun.tools.javac.comp.Attr.checkMethod(Attr.java:3809)
        at com.sun.tools.javac.comp.Attr.checkIdInternal(Attr.java:3615)
        at com.sun.tools.javac.comp.Attr.checkMethodIdInternal(Attr.java:3522)
        at com.sun.tools.javac.comp.Attr.checkMethodId(Attr.java:3501)
        at com.sun.tools.javac.comp.Attr.checkId(Attr.java:3488)
        at com.sun.tools.javac.comp.Attr.visitSelect(Attr.java:3370)
        at com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1897)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1843)
        at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:656)
        at com.sun.tools.javac.comp.Attr.visitExec(Attr.java:1611)
        at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1296)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:692)
        at com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1142)
        at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:909)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1035)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
        at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:607)
        at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:676)
        at com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4342)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4252)
        at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4181)
        at com.sun.tools.javac.comp.Attr.attrib(Attr.java:4156)
        at com.sun.tools.javac.main.JavaCompiler.attribute(JavaCompiler.java:1248)
        at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:901)
        at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:860)
        at com.sun.tools.javac.main.Main.compile(Main.java:523)
        at com.sun.tools.javac.main.Main.compile(Main.java:381)
        at com.sun.tools.javac.main.Main.compile(Main.java:370)
        at com.sun.tools.javac.main.Main.compile(Main.java:361)
        at com.sun.tools.javac.Main.compile(Main.java:56)
        at com.sun.tools.javac.Main.main(Main.java:42)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
/******************************************************************************
 * 
 * Filename:     JavacError.java
 * Description:
 * 
 * (c) COPYRIGHT Queen City Software, Inc. 2014 All Rights Reserved
 * No part of this copyrighted work may be reproduced, modified, or distributed
 * in any form or by any means without the prior written permission of Queen
 * City Software, Inc.
 * 
 * $Id$
 * Notes:
 * 
 *****************************************************************************/
package com.qcsoftware.products.fulfillmentmgr;

import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Consumer;

/**
 * The {@code JavacError} class.
 */
public class JavacError
{
  public static void main(String[] args)
  {
    AtomicInteger status = new AtomicInteger(0);
    String response = "";

    /*
     * This way causes exception in javac
     */
    new DbResource()
      .transaction(DbResource.actions(
                     dbr -> System.out.println("hello world")),
                   res -> handleException(res,
                                          response,
                                          status),
                   DbResource::commitAndClose);
    
    /*
     * This way works in javac
     */
//    ConsumerThrower<DbResource, RuntimeException> catcher = 
//      res -> handleException(res,
//                             response,
//                             status);    
//    new DbResource()
//      .transaction(DbResource.actions(
//                     dbr -> System.out.println("hello world")),
//                   catcher,
//                   DbResource::commitAndClose);
  }

  private static ConsumerThrower<DbResource, RuntimeException> handleException(DbResource res,
                                                                               String response,
                                                                               AtomicInteger status)
  {
    throw new UnsupportedOperationException("Not supported yet.");
  }
  
  private static class DbResource
  {
    @SafeVarargs
    public static final ConsumerThrower<DbResource, ?>[] actions(
        ConsumerThrower<DbResource, ?>... action)
    {
      return action;
    }    
    
    public static void commitAndClose(DbResource dbr)
    {
      throw new UnsupportedOperationException("Not supported yet.");
    }
    
    public final <T extends Throwable> void transaction(
        ConsumerThrower<DbResource, ?>[] action,
        ConsumerThrower<DbResource, T> catcher,
        Consumer<DbResource> finalizer
        ) throws T
    {
      throw new UnsupportedOperationException("Not supported yet.");
    }    
  }
  
  @FunctionalInterface
  public static interface ConsumerThrower<A, T extends Throwable>
  {
    public void accept(A arg) throws T;
  }
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
/******************************************************************************
 * 
 * Filename:     JavacError.java
 * Description:
 * 
 * (c) COPYRIGHT Queen City Software, Inc. 2014 All Rights Reserved
 * No part of this copyrighted work may be reproduced, modified, or distributed
 * in any form or by any means without the prior written permission of Queen
 * City Software, Inc.
 * 
 * $Id$
 * Notes:
 * 
 *****************************************************************************/
package com.qcsoftware.products.fulfillmentmgr;

import java.util.concurrent.atomic.AtomicInteger;
import java.util.function.Consumer;

/**
 * The {@code JavacError} class.
 */
public class JavacError
{
  public static void main(String[] args)
  {
    AtomicInteger status = new AtomicInteger(0);
    String response = "";

    /*
     * This way causes exception in javac
     */
//    new DbResource()
//      .transaction(DbResource.actions(
//                     dbr -> System.out.println("hello world")),
//                   res -> handleException(res,
//                                          response,
//                                          status),
//                   DbResource::commitAndClose);
    
    /*
     * This way works in javac
     */
    ConsumerThrower<DbResource, RuntimeException> catcher = 
      res -> handleException(res,
                             response,
                             status);    
    new DbResource()
      .transaction(DbResource.actions(
                     dbr -> System.out.println("hello world")),
                   catcher,
                   DbResource::commitAndClose);
  }

  private static ConsumerThrower<DbResource, RuntimeException> handleException(DbResource res,
                                                                               String response,
                                                                               AtomicInteger status)
  {
    throw new UnsupportedOperationException("Not supported yet.");
  }
  
  private static class DbResource
  {
    @SafeVarargs
    public static final ConsumerThrower<DbResource, ?>[] actions(
        ConsumerThrower<DbResource, ?>... action)
    {
      return action;
    }    
    
    public static void commitAndClose(DbResource dbr)
    {
      throw new UnsupportedOperationException("Not supported yet.");
    }
    
    public final <T extends Throwable> void transaction(
        ConsumerThrower<DbResource, ?>[] action,
        ConsumerThrower<DbResource, T> catcher,
        Consumer<DbResource> finalizer
        ) throws T
    {
      throw new UnsupportedOperationException("Not supported yet.");
    }    
  }
  
  @FunctionalInterface
  public static interface ConsumerThrower<A, T extends Throwable>
  {
    public void accept(A arg) throws T;
  }
}
Comments
This is a duplicate of JDK-8041713 which has a fix for JDK 9 b17. Though the issue is reproducible in JDK 8u31. When tested, it seems resolved in JDK 8u40 ea b23 and JDK 9 ea b49.
24-02-2015