JDK-8144974 : Uncompilable method references to constructors when using generics
  • Type: Bug
  • Component: tools
  • Sub-Component: javac
  • Affected Version: 8u11
  • Priority: P4
  • Status: Closed
  • Resolution: Duplicate
  • OS: windows_8
  • CPU: x86
  • Submitted: 2015-12-05
  • Updated: 2015-12-10
  • Resolved: 2015-12-10
Related Reports
Duplicate :  
JDK-8132372 - NullPointerException in com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer
Relates :  
JDK-8065986 - Compiler fails to NullPointerException when calling super with Object<>()
Description
FULL PRODUCT VERSION :
java version "1.8.0_60"
Java(TM) SE Runtime Environment (build 1.8.0_60-b27)
Java HotSpot(TM) 64-Bit Server VM (build 25.60-b23, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 10.0.10240]

EXTRA RELEVANT SYSTEM CONFIGURATION :
Netbeans 8.0.2

A DESCRIPTION OF THE PROBLEM :
(Appears to be a problem on Netbeans only, eclipse appears unaffected)

Given a method that takes two Suppliers, both of similar but different Generics themselves (e.g. both Suppliers of List, but the List of two distinct types); calling the method using method references to the a constructor of a single class implementing List will result in the compiler failing.

Tested versions:
32-bit: 8u66
64-bit: 8u45, 8u60, 8u66

Tested on Microsoft Windows [Version 6.1.7601], Eclipse Luna 4.4.0, 32-bit 8u45 and 8u66 and was unable to reproduce the error.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Valid compilation.
ACTUAL -
Compilation fails with the following exception

ERROR MESSAGES/STACK TRACES THAT OCCUR :
An exception has occurred in the compiler (1.8.0_11). 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$AbstractAssignAnalyzer.visitIdent(Flow.java:2327)
	at com.sun.tools.javac.tree.JCTree$JCIdent.accept(JCTree.java:2005)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.tree.TreeScanner.visitReference(TreeScanner.java:268)
	at com.sun.tools.javac.tree.JCTree$JCMemberReference.accept(JCTree.java:1967)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scanExpr(Flow.java:1596)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scanExprs(Flow.java:1608)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitApply(Flow.java:2205)
	at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1459)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.tree.TreeScanner.visitExec(TreeScanner.java:175)
	at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1290)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitBlock(Flow.java:1815)
	at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:903)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitMethodDef(Flow.java:1753)
	at com.sun.tools.javac.comp.Flow$AssignAnalyzer.visitMethodDef(Flow.java:2507)
	at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:772)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.visitClassDef(Flow.java:1705)
	at com.sun.tools.javac.comp.Flow$AssignAnalyzer.visitClassDef(Flow.java:2486)
	at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:687)
	at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:49)
	at com.sun.tools.javac.comp.Flow$BaseAnalyzer.scan(Flow.java:389)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.scan(Flow.java:1367)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.analyzeTree(Flow.java:2370)
	at com.sun.tools.javac.comp.Flow$AbstractAssignAnalyzer.analyzeTree(Flow.java:2353)
	at com.sun.tools.javac.comp.Flow.analyzeTree(Flow.java:210)
	at com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1325)
	at com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1299)
	at com.sun.tools.javac.main.JavaCompiler.compile2(JavaCompiler.java:904)
	at com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:863)
	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 sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.apache.tools.ant.taskdefs.compilers.Javac13.execute(Javac13.java:56)
	at org.apache.tools.ant.taskdefs.Javac.compile(Javac.java:1159)
	at org.apache.tools.ant.taskdefs.Javac.execute(Javac.java:935)
	at org.netbeans.modules.java.source.ant.JavacTask.execute(JavacTask.java:145)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:292)
	at sun.reflect.GeneratedMethodAccessor204.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.taskdefs.Sequential.execute(Sequential.java:68)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:292)
	at sun.reflect.GeneratedMethodAccessor204.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.taskdefs.MacroInstance.execute(MacroInstance.java:396)
	at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:292)
	at sun.reflect.GeneratedMethodAccessor204.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:483)
	at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
	at org.apache.tools.ant.Task.perform(Task.java:348)
	at org.apache.tools.ant.Target.execute(Target.java:435)
	at org.apache.tools.ant.Target.performTasks(Target.java:456)
	at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1393)
	at org.apache.tools.ant.Project.executeTarget(Project.java:1364)
	at org.apache.tools.ant.helper.DefaultExecutor.executeTargets(DefaultExecutor.java:41)
	at org.apache.tools.ant.Project.executeTargets(Project.java:1248)
	at org.apache.tools.ant.module.bridge.impl.BridgeImpl.run(BridgeImpl.java:286)
	at org.apache.tools.ant.module.run.TargetExecutor.run(TargetExecutor.java:555)
	at org.netbeans.core.execution.RunClassThread.run(RunClassThread.java:153)

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.List;
import java.util.function.Supplier;

public class SubClass extends SuperClass<Integer, String> {

    public SubClass() {
        super(ArrayList::new, ArrayList::new);
//        super(ArrayList<A>::new, LinkedList<B>::new); // Also fails to compile...
    }

}

class SuperClass<A,B> {
    
    public SuperClass(Supplier<List<A>> supA, Supplier<List<B>> supB) {
        supA.get();
        supB.get();
    }

}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Using the () -> {} notation compiles correctly.
Comments
Duplicate issue of JDK-8132372
09-12-2015