public HierarchyResolver(
INameEnvironment nameEnvironment,
Map settings,
HierarchyBuilder builder,
IProblemFactory problemFactory) {
// create a problem handler with the 'exit after all problems' handling policy
this.options = new CompilerOptions(settings);
IErrorHandlingPolicy policy = DefaultErrorHandlingPolicies.exitAfterAllProblems();
ProblemReporter problemReporter = new ProblemReporter(policy, this.options, problemFactory);
LookupEnvironment environment =
new LookupEnvironment(this, this.options, problemReporter, nameEnvironment);
environment.mayTolerateMissingType = true;
setEnvironment(environment, builder);
}
public boolean checkUnsafeCast(
Scope scope,
TypeBinding castType,
TypeBinding expressionType,
TypeBinding match,
boolean isNarrowing) {
if (TypeBinding.equalsEquals(match, castType)) {
if (!isNarrowing
&& TypeBinding.equalsEquals(
match,
this.resolvedType
.leafComponentType()) // do not tag as unnecessary when recursing through upper
// bounds
&& !(expressionType.isParameterizedType()
&& expressionType.isProvablyDistinct(castType))) {
tagAsUnnecessaryCast(scope, castType);
}
return true;
}
if (match != null) {
if (isNarrowing
? match.isProvablyDistinct(expressionType)
: castType.isProvablyDistinct(match)) {
return false;
}
}
switch (castType.kind()) {
case Binding.PARAMETERIZED_TYPE:
if (!castType.isReifiable()) {
if (match == null) { // unrelated types
this.bits |= ASTNode.UnsafeCast;
return true;
}
switch (match.kind()) {
case Binding.PARAMETERIZED_TYPE:
if (isNarrowing) {
// [JLS 5.5] T <: S
if (expressionType.isRawType() || !expressionType.isEquivalentTo(match)) {
this.bits |= ASTNode.UnsafeCast;
return true;
}
// [JLS 5.5] S has no subtype X != T, such that |X| == |T|
// if I2<T,U> extends I1<T>, then cast from I1<T> to I2<T,U> is unchecked
ParameterizedTypeBinding paramCastType = (ParameterizedTypeBinding) castType;
ParameterizedTypeBinding paramMatch = (ParameterizedTypeBinding) match;
// easy case if less parameters on match
TypeBinding[] castArguments = paramCastType.arguments;
int length = castArguments == null ? 0 : castArguments.length;
if (paramMatch.arguments == null || length > paramMatch.arguments.length) {
this.bits |= ASTNode.UnsafeCast;
} else if ((paramCastType.tagBits
& (TagBits.HasDirectWildcard | TagBits.HasTypeVariable))
!= 0) {
// verify alternate cast type, substituting different type arguments
nextAlternateArgument:
for (int i = 0; i < length; i++) {
switch (castArguments[i].kind()) {
case Binding.WILDCARD_TYPE:
case Binding.TYPE_PARAMETER:
break; // check substituting with other
default:
continue nextAlternateArgument; // no alternative possible
}
TypeBinding[] alternateArguments;
// need to clone for each iteration to avoid env paramtype cache interference
System.arraycopy(
paramCastType.arguments,
0,
alternateArguments = new TypeBinding[length],
0,
length);
alternateArguments[i] = scope.getJavaLangObject();
LookupEnvironment environment = scope.environment();
ParameterizedTypeBinding alternateCastType =
environment.createParameterizedType(
(ReferenceBinding) castType.erasure(),
alternateArguments,
castType.enclosingType());
if (TypeBinding.equalsEquals(
alternateCastType.findSuperTypeOriginatingFrom(expressionType), match)) {
this.bits |= ASTNode.UnsafeCast;
break;
}
}
}
return true;
} else {
// [JLS 5.5] T >: S
if (!match.isEquivalentTo(castType)) {
this.bits |= ASTNode.UnsafeCast;
return true;
}
}
break;
case Binding.RAW_TYPE:
this.bits |=
ASTNode.UnsafeCast; // upcast since castType is known to be bound paramType
return true;
default:
if (isNarrowing) {
// match is not parameterized or raw, then any other subtype of match will erase to
// |T|
this.bits |= ASTNode.UnsafeCast;
return true;
}
break;
}
}
break;
case Binding.ARRAY_TYPE:
TypeBinding leafType = castType.leafComponentType();
if (isNarrowing && (!leafType.isReifiable() || leafType.isTypeVariable())) {
this.bits |= ASTNode.UnsafeCast;
return true;
}
break;
case Binding.TYPE_PARAMETER:
this.bits |= ASTNode.UnsafeCast;
return true;
// (disabled) https://bugs.eclipse.org/bugs/show_bug.cgi?id=240807
// case Binding.TYPE :
// if (isNarrowing && match == null && expressionType.isParameterizedType()) {
// this.bits |= ASTNode.UnsafeCast;
// return true;
// }
// break;
}
if (!isNarrowing
&& TypeBinding.equalsEquals(
match,
this.resolvedType
.leafComponentType())) { // do not tag as unnecessary when recursing through upper
// bounds
tagAsUnnecessaryCast(scope, castType);
}
return true;
}