/**
* Casting an enclosing instance will considered as useful if removing it would actually bind to a
* different type
*/
public static void checkNeedForEnclosingInstanceCast(
BlockScope scope,
Expression enclosingInstance,
TypeBinding enclosingInstanceType,
TypeBinding memberType) {
if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
== ProblemSeverities.Ignore) return;
TypeBinding castedExpressionType = ((CastExpression) enclosingInstance).expression.resolvedType;
if (castedExpressionType == null) return; // cannot do better
// obvious identity cast
if (TypeBinding.equalsEquals(castedExpressionType, enclosingInstanceType)) {
scope.problemReporter().unnecessaryCast((CastExpression) enclosingInstance);
} else if (castedExpressionType == TypeBinding.NULL) {
return; // tolerate null enclosing instance cast
} else {
TypeBinding alternateEnclosingInstanceType = castedExpressionType;
if (castedExpressionType.isBaseType() || castedExpressionType.isArrayType())
return; // error case
if (TypeBinding.equalsEquals(
memberType,
scope.getMemberType(
memberType.sourceName(), (ReferenceBinding) alternateEnclosingInstanceType))) {
scope.problemReporter().unnecessaryCast((CastExpression) enclosingInstance);
}
}
}
/**
* Cast expressions will considered as useful if removing them all would actually bind to a
* different method (no fine grain analysis on per casted argument basis, simply separate widening
* cast from narrowing ones)
*/
public static void checkNeedForArgumentCasts(
BlockScope scope,
Expression receiver,
TypeBinding receiverType,
MethodBinding binding,
Expression[] arguments,
TypeBinding[] argumentTypes,
final InvocationSite invocationSite) {
if (scope.compilerOptions().getSeverity(CompilerOptions.UnnecessaryTypeCheck)
== ProblemSeverities.Ignore) return;
int length = argumentTypes.length;
// iterate over arguments, and retrieve original argument types (before cast)
TypeBinding[] rawArgumentTypes = argumentTypes;
for (int i = 0; i < length; i++) {
Expression argument = arguments[i];
if (argument instanceof CastExpression) {
// narrowing conversion on base type may change value, thus necessary
if ((argument.bits & ASTNode.UnnecessaryCast) == 0 && argument.resolvedType.isBaseType()) {
continue;
}
TypeBinding castedExpressionType = ((CastExpression) argument).expression.resolvedType;
if (castedExpressionType == null) return; // cannot do better
// obvious identity cast
if (TypeBinding.equalsEquals(castedExpressionType, argumentTypes[i])) {
scope.problemReporter().unnecessaryCast((CastExpression) argument);
} else if (castedExpressionType == TypeBinding.NULL) {
continue; // tolerate null argument cast
} else if ((argument.implicitConversion & TypeIds.BOXING) != 0) {
continue; // boxing has a side effect: (int) char is not boxed as simple char
} else {
if (rawArgumentTypes == argumentTypes) {
System.arraycopy(
rawArgumentTypes, 0, rawArgumentTypes = new TypeBinding[length], 0, length);
}
// retain original argument type
rawArgumentTypes[i] = castedExpressionType;
}
}
}
// perform alternate lookup with original types
if (rawArgumentTypes != argumentTypes) {
checkAlternateBinding(
scope,
receiver,
receiverType,
binding,
arguments,
argumentTypes,
rawArgumentTypes,
invocationSite);
}
}
/*
* Creates the super class handle of the given type.
* Returns null if the type has no super class.
* Adds the simple name to the hierarchy missing types if the class is not found and returns null.
*/
private IType findSuperClass(IGenericType type, ReferenceBinding typeBinding) {
ReferenceBinding superBinding = typeBinding.superclass();
if (superBinding != null) {
superBinding = (ReferenceBinding) superBinding.erasure();
if (typeBinding.isHierarchyInconsistent()) {
if (superBinding.problemId() == ProblemReasons.NotFound) {
this.hasMissingSuperClass = true;
this.builder.hierarchy.missingTypes.add(
new String(superBinding.sourceName)); // note: this could be Map$Entry
return null;
} else if ((superBinding.id == TypeIds.T_JavaLangObject)) {
char[] superclassName;
char separator;
if (type instanceof IBinaryType) {
superclassName = ((IBinaryType) type).getSuperclassName();
separator = '/';
} else if (type instanceof ISourceType) {
superclassName = ((ISourceType) type).getSuperclassName();
separator = '.';
} else if (type instanceof HierarchyType) {
superclassName = ((HierarchyType) type).superclassName;
separator = '.';
} else {
return null;
}
if (superclassName
!= null) { // check whether subclass of Object due to broken hierarchy (as opposed to
// explicitly extending it)
int lastSeparator = CharOperation.lastIndexOf(separator, superclassName);
char[] simpleName =
lastSeparator == -1
? superclassName
: CharOperation.subarray(
superclassName, lastSeparator + 1, superclassName.length);
if (!CharOperation.equals(simpleName, TypeConstants.OBJECT)) {
this.hasMissingSuperClass = true;
this.builder.hierarchy.missingTypes.add(new String(simpleName));
return null;
}
}
}
}
for (int t = this.typeIndex; t >= 0; t--) {
if (TypeBinding.equalsEquals(this.typeBindings[t], superBinding)) {
return this.builder.getHandle(this.typeModels[t], superBinding);
}
}
}
return null;
}
private boolean subTypeOfType(ReferenceBinding subType, ReferenceBinding typeBinding) {
if (typeBinding == null || subType == null) return false;
if (TypeBinding.equalsEquals(subType, typeBinding)) return true;
ReferenceBinding superclass = subType.superclass();
if (superclass != null) superclass = (ReferenceBinding) superclass.erasure();
// if (superclass != null && superclass.id == TypeIds.T_JavaLangObject &&
// subType.isHierarchyInconsistent()) return false;
if (subTypeOfType(superclass, typeBinding)) return true;
ReferenceBinding[] superInterfaces = subType.superInterfaces();
if (superInterfaces != null) {
for (int i = 0, length = superInterfaces.length; i < length; i++) {
ReferenceBinding superInterface = (ReferenceBinding) superInterfaces[i].erasure();
if (subTypeOfType(superInterface, typeBinding)) return true;
}
}
return false;
}
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;
}
/*
* Returns the handles of the super interfaces of the given type.
* Adds the simple name to the hierarchy missing types if an interface is not found (but don't put null in the returned array)
*/
private IType[] findSuperInterfaces(IGenericType type, ReferenceBinding typeBinding) {
char[][] superInterfaceNames;
char separator;
if (type instanceof IBinaryType) {
superInterfaceNames = ((IBinaryType) type).getInterfaceNames();
separator = '/';
} else if (type instanceof ISourceType) {
ISourceType sourceType = (ISourceType) type;
if (sourceType.isAnonymous()) { // if anonymous type
if (typeBinding.superInterfaces() != null && typeBinding.superInterfaces().length > 0) {
superInterfaceNames = new char[][] {sourceType.getSuperclassName()};
} else {
superInterfaceNames = sourceType.getInterfaceNames();
}
} else {
if (TypeDeclaration.kind(sourceType.getModifiers()) == TypeDeclaration.ANNOTATION_TYPE_DECL)
superInterfaceNames =
new char[][] {TypeConstants.CharArray_JAVA_LANG_ANNOTATION_ANNOTATION};
else superInterfaceNames = sourceType.getInterfaceNames();
}
separator = '.';
} else if (type instanceof HierarchyType) {
HierarchyType hierarchyType = (HierarchyType) type;
if (hierarchyType.isAnonymous()) { // if anonymous type
if (typeBinding.superInterfaces() != null && typeBinding.superInterfaces().length > 0) {
superInterfaceNames = new char[][] {hierarchyType.superclassName};
} else {
superInterfaceNames = hierarchyType.superInterfaceNames;
}
} else {
superInterfaceNames = hierarchyType.superInterfaceNames;
}
separator = '.';
} else {
return null;
}
ReferenceBinding[] interfaceBindings = typeBinding.superInterfaces();
int bindingIndex = 0;
int bindingLength = interfaceBindings == null ? 0 : interfaceBindings.length;
int length = superInterfaceNames == null ? 0 : superInterfaceNames.length;
IType[] superinterfaces = new IType[length];
int index = 0;
next:
for (int i = 0; i < length; i++) {
char[] superInterfaceName = superInterfaceNames[i];
int end = superInterfaceName.length;
// find the end of simple name
int genericStart = CharOperation.indexOf(Signature.C_GENERIC_START, superInterfaceName);
if (genericStart != -1) end = genericStart;
// find the start of simple name
int lastSeparator = CharOperation.lastIndexOf(separator, superInterfaceName, 0, end);
int start = lastSeparator + 1;
// case of binary inner type -> take the last part
int lastDollar = CharOperation.lastIndexOf('$', superInterfaceName, start);
if (lastDollar != -1) start = lastDollar + 1;
char[] simpleName = CharOperation.subarray(superInterfaceName, start, end);
if (bindingIndex < bindingLength) {
ReferenceBinding interfaceBinding =
(ReferenceBinding) interfaceBindings[bindingIndex].erasure();
// ensure that the binding corresponds to the interface defined by the user
if (CharOperation.equals(simpleName, interfaceBinding.sourceName)) {
bindingIndex++;
for (int t = this.typeIndex; t >= 0; t--) {
if (TypeBinding.equalsEquals(this.typeBindings[t], interfaceBinding)) {
IType handle = this.builder.getHandle(this.typeModels[t], interfaceBinding);
if (handle != null) {
superinterfaces[index++] = handle;
continue next;
}
}
}
}
}
this.builder.hierarchy.missingTypes.add(new String(simpleName));
}
if (index != length)
System.arraycopy(superinterfaces, 0, superinterfaces = new IType[index], 0, index);
return superinterfaces;
}
