JDK-8217861 : Compiler throws NPE at com.sun.tools.javac.comp.Check$Validator.visitSelect
  • Type: Bug
  • Component: tools
  • Sub-Component: javac
  • Affected Version: 8u202
  • Priority: P4
  • Status: Closed
  • Resolution: Duplicate
  • OS: generic
  • CPU: x86_64
  • Submitted: 2019-01-24
  • Updated: 2019-01-28
  • Resolved: 2019-01-28
Related Reports
Duplicate :  
JDK-8078473 - javac diamond finder crashes when used to build java.base module
Description
ADDITIONAL SYSTEM INFORMATION :
Hollis-MacBook-Pro:~ hwaite$ sw_vers
ProductName:	Mac OS X
ProductVersion:	10.14.2
BuildVersion:	18C54
Hollis-MacBook-Pro:~ hwaite$ java -version
java version "1.8.0_202-ea"
Java(TM) SE Runtime Environment (build 1.8.0_202-ea-b03)
Java HotSpot(TM) 64-Bit Server VM (build 25.202-b03, mixed mode)

A DESCRIPTION OF THE PROBLEM :
Compilation fails when we aggressively mix partially qualified, nested and/or wildcarded generics.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attempt to compile code.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Code compiles.
ACTUAL -
Hollis-MacBook-Pro:~ hwaite$ javac Foo.java Bar.java
An exception has occurred in the compiler (1.8.0_202-ea). 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.NullPointerException
	at com.sun.tools.javac.comp.Check$Validator.visitSelect(Check.java:1310)
	at com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1897)
	at com.sun.tools.javac.comp.Check$Validator.validateTree(Check.java:1359)
	at com.sun.tools.javac.comp.Check$Validator.visitWildcard(Check.java:1305)
	at com.sun.tools.javac.tree.JCTree$JCWildcard.accept(JCTree.java:2253)
	at com.sun.tools.javac.comp.Check$Validator.validateTree(Check.java:1359)
	at com.sun.tools.javac.comp.Check$Validator.visitTypeApply(Check.java:1280)
	at com.sun.tools.javac.tree.JCTree$JCTypeApply.accept(JCTree.java:2135)
	at com.sun.tools.javac.comp.Check$Validator.validateTree(Check.java:1359)
	at com.sun.tools.javac.comp.Check$Validator.visitTypeApply(Check.java:1280)
	at com.sun.tools.javac.tree.JCTree$JCTypeApply.accept(JCTree.java:2135)
	at com.sun.tools.javac.comp.Check$Validator.validateTree(Check.java:1359)
	at com.sun.tools.javac.comp.Check.validate(Check.java:1230)
	at com.sun.tools.javac.comp.Attr.visitVarDef(Attr.java:1055)
	at com.sun.tools.javac.tree.JCTree$JCVariableDecl.accept(JCTree.java:852)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
	at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:661)
	at com.sun.tools.javac.comp.Attr.visitLambda(Attr.java:2316)
	at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.DeferredAttr.attribSpeculative(DeferredAttr.java:387)
	at com.sun.tools.javac.comp.DeferredAttr$2.complete(DeferredAttr.java:280)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:246)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:233)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.recover(DeferredAttr.java:883)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.typeOf(DeferredAttr.java:872)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredTypeMap.apply(DeferredAttr.java:839)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.apply(DeferredAttr.java:862)
	at com.sun.tools.javac.code.Type.map(Type.java:221)
	at com.sun.tools.javac.code.Type$MethodType.map(Type.java:1189)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredTypeMap.apply(DeferredAttr.java:836)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.apply(DeferredAttr.java:862)
	at com.sun.tools.javac.code.Type$ForAll.map(Type.java:1429)
	at com.sun.tools.javac.comp.Attr.checkMethodIdInternal(Attr.java:3522)
	at com.sun.tools.javac.comp.Attr.checkMethodId(Attr.java:3502)
	at com.sun.tools.javac.comp.Attr.checkId(Attr.java:3489)
	at com.sun.tools.javac.comp.Attr.visitSelect(Attr.java:3371)
	at com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1897)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1825)
	at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitSelect(Attr.java:3250)
	at com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:1897)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1825)
	at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitLambda(Attr.java:2398)
	at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.DeferredAttr.attribSpeculative(DeferredAttr.java:387)
	at com.sun.tools.javac.comp.DeferredAttr$2.complete(DeferredAttr.java:280)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:246)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:233)
	at com.sun.tools.javac.comp.Resolve$MethodResultInfo.check(Resolve.java:1008)
	at com.sun.tools.javac.comp.Resolve$4.checkArg(Resolve.java:835)
	at com.sun.tools.javac.comp.Resolve$AbstractMethodCheck.argumentsAcceptable(Resolve.java:735)
	at com.sun.tools.javac.comp.Resolve$4.argumentsAcceptable(Resolve.java:844)
	at com.sun.tools.javac.comp.Infer.instantiateMethod(Infer.java:162)
	at com.sun.tools.javac.comp.Resolve.rawInstantiate(Resolve.java:567)
	at com.sun.tools.javac.comp.Resolve.selectBest(Resolve.java:1446)
	at com.sun.tools.javac.comp.Resolve.findMethodInScope(Resolve.java:1633)
	at com.sun.tools.javac.comp.Resolve.findMethod(Resolve.java:1704)
	at com.sun.tools.javac.comp.Resolve.findMethod(Resolve.java:1677)
	at com.sun.tools.javac.comp.Resolve.findFun(Resolve.java:1840)
	at com.sun.tools.javac.comp.Resolve$8.doLookup(Resolve.java:2404)
	at com.sun.tools.javac.comp.Resolve$BasicLookupHelper.lookup(Resolve.java:3097)
	at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3348)
	at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3333)
	at com.sun.tools.javac.comp.Resolve.resolveMethod(Resolve.java:2400)
	at com.sun.tools.javac.comp.Attr.visitIdent(Attr.java:3166)
	at com.sun.tools.javac.tree.JCTree$JCIdent.accept(JCTree.java:2011)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1825)
	at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.DeferredAttr.attribSpeculative(DeferredAttr.java:387)
	at com.sun.tools.javac.comp.DeferredAttr$2.complete(DeferredAttr.java:280)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:246)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:233)
	at com.sun.tools.javac.comp.Resolve$MethodResultInfo.check(Resolve.java:1008)
	at com.sun.tools.javac.comp.Resolve$4.checkArg(Resolve.java:835)
	at com.sun.tools.javac.comp.Resolve$AbstractMethodCheck.argumentsAcceptable(Resolve.java:735)
	at com.sun.tools.javac.comp.Resolve$4.argumentsAcceptable(Resolve.java:844)
	at com.sun.tools.javac.comp.Infer.instantiateMethod(Infer.java:162)
	at com.sun.tools.javac.comp.Resolve.rawInstantiate(Resolve.java:567)
	at com.sun.tools.javac.comp.Resolve.selectBest(Resolve.java:1446)
	at com.sun.tools.javac.comp.Resolve.findDiamond(Resolve.java:2660)
	at com.sun.tools.javac.comp.Resolve.access$1000(Resolve.java:80)
	at com.sun.tools.javac.comp.Resolve$12.doLookup(Resolve.java:2595)
	at com.sun.tools.javac.comp.Resolve$BasicLookupHelper.lookup(Resolve.java:3097)
	at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3348)
	at com.sun.tools.javac.comp.Resolve.lookupMethod(Resolve.java:3333)
	at com.sun.tools.javac.comp.Resolve.resolveDiamond(Resolve.java:2591)
	at com.sun.tools.javac.comp.Attr.visitNewClass(Attr.java:2040)
	at com.sun.tools.javac.tree.JCTree$JCNewClass.accept(JCTree.java:1516)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.visitLambda(Attr.java:2398)
	at com.sun.tools.javac.tree.JCTree$JCLambda.accept(JCTree.java:1624)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.DeferredAttr$2.complete(DeferredAttr.java:285)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:246)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredType.check(DeferredAttr.java:233)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.recover(DeferredAttr.java:883)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.typeOf(DeferredAttr.java:872)
	at com.sun.tools.javac.comp.Resolve$ResolveDeferredRecoveryMap.typeOf(Resolve.java:2310)
	at com.sun.tools.javac.comp.DeferredAttr$DeferredTypeMap.apply(DeferredAttr.java:839)
	at com.sun.tools.javac.comp.DeferredAttr$RecoveryDeferredTypeMap.apply(DeferredAttr.java:862)
	at com.sun.tools.javac.code.Type.map(Type.java:221)
	at com.sun.tools.javac.code.Type.map(Type.java:220)
	at com.sun.tools.javac.comp.Attr.checkMethod(Attr.java:3873)
	at com.sun.tools.javac.comp.Attr.checkIdInternal(Attr.java:3616)
	at com.sun.tools.javac.comp.Attr.checkMethodIdInternal(Attr.java:3523)
	at com.sun.tools.javac.comp.Attr.checkMethodId(Attr.java:3502)
	at com.sun.tools.javac.comp.Attr.checkId(Attr.java:3489)
	at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1808)
	at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1465)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:625)
	at com.sun.tools.javac.comp.Attr.visitExec(Attr.java:1593)
	at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1296)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
	at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:661)
	at com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1124)
	at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:909)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
	at com.sun.tools.javac.comp.Attr.visitMethodDef(Attr.java:1013)
	at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:778)
	at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:576)
	at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:645)
	at com.sun.tools.javac.comp.Attr.attribClassBody(Attr.java:4364)
	at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4272)
	at com.sun.tools.javac.comp.Attr.attribClass(Attr.java:4201)
	at com.sun.tools.javac.comp.Attr.attrib(Attr.java:4176)
	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)

---------- BEGIN SOURCE ----------
import java.util.Optional;
import java.util.function.Function;

import javafx.beans.property.SimpleObjectProperty;
import javafx.beans.value.ObservableValue;
import javafx.collections.ObservableList;

public class Foo<T> {
	public Foo(
		ObservableList<? extends T> pArg1,
		ObservableValue<? extends Function<? super T,ObservableValue<?>>> pArg2
	) {
		this(
			pArg1,
			pVal -> new Bar<>(
				map(
					pArg2,
					pFunction -> Optional.ofNullable(pFunction).map(
						pFunc -> pFunc.apply(pVal)
					).orElse(new SimpleObjectProperty())
				)
			)
		);
	}

	public Foo(
		ObservableList<? extends T> pArg1,
		Function<? super T,? extends ObservableValue<?>> pArg2
	) {
	}

    public static <T, U> ObservableValue<U> map(ObservableValue<T> pArg1, Function<T, U> pArg2) {
        return new SimpleObjectProperty<>();
    }
}

import javafx.beans.value.ObservableValue;
import javafx.beans.value.ObservableValueBase;

public class Bar<T> extends ObservableValueBase<T> {
	public Bar(ObservableValue<? extends ObservableValue<? extends T>> pArg1) {}

	@Override public T getValue() {return null;}
	public static void main(String[] pArgs) {}
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Remove wildcards from constructor

FREQUENCY : always
Comments
Closing this as a duplicate of JDK-8078473, which has been fixed in JDK 9.
28-01-2019