/**
* Returns the given reference value that may or may not be null, ensuring that it is a
* TypedReferenceValue, not a subclass.
*/
private static ReferenceValue typedReferenceValue(
TypedReferenceValue referenceValue, boolean mayBeNull) {
return referenceValue.getClass() == TypedReferenceValue.class
? referenceValue.generalizeMayBeNull(mayBeNull)
: new TypedReferenceValue(referenceValue.type, referenceValue.referencedClass, mayBeNull);
}
public ReferenceValue generalize(TypedReferenceValue other) {
// If both types are identical, the generalization is the same too.
if (this.equals(other)) {
return this;
}
String thisType = this.type;
String otherType = other.type;
// If both types are nul, the generalization is null too.
if (thisType == null && otherType == null) {
return ValueFactory.REFERENCE_VALUE_NULL;
}
// If this type is null, the generalization is the other type, maybe null.
if (thisType == null) {
return other.generalizeMayBeNull(true);
}
// If the other type is null, the generalization is this type, maybe null.
if (otherType == null) {
return this.generalizeMayBeNull(true);
}
boolean mayBeNull = this.mayBeNull || other.mayBeNull;
// If the two types are equal, the generalization remains the same, maybe null.
if (thisType.equals(otherType)) {
return typedReferenceValue(this, mayBeNull);
}
// Start taking into account the type dimensions.
int thisDimensionCount = ClassUtil.internalArrayTypeDimensionCount(thisType);
int otherDimensionCount = ClassUtil.internalArrayTypeDimensionCount(otherType);
int commonDimensionCount = Math.min(thisDimensionCount, otherDimensionCount);
if (thisDimensionCount == otherDimensionCount) {
// See if we can take into account the referenced classes.
Clazz thisReferencedClass = this.referencedClass;
Clazz otherReferencedClass = other.referencedClass;
if (thisReferencedClass != null && otherReferencedClass != null) {
// Is one class simply an extension of the other one?
if (thisReferencedClass.extendsOrImplements(otherReferencedClass)) {
return typedReferenceValue(other, mayBeNull);
}
if (otherReferencedClass.extendsOrImplements(thisReferencedClass)) {
return typedReferenceValue(this, mayBeNull);
}
// Do the classes have a non-trivial common superclass?
Clazz commonClass = findCommonClass(thisReferencedClass, otherReferencedClass, false);
if (commonClass.getName().equals(ClassConstants.NAME_JAVA_LANG_OBJECT)) {
// Otherwise, do the classes have a common interface?
Clazz commonInterface = findCommonClass(thisReferencedClass, otherReferencedClass, true);
if (commonInterface != null) {
commonClass = commonInterface;
}
}
return new TypedReferenceValue(
commonDimensionCount == 0
? commonClass.getName()
: ClassUtil.internalArrayTypeFromClassName(
commonClass.getName(), commonDimensionCount),
commonClass,
mayBeNull);
}
} else if (thisDimensionCount > otherDimensionCount) {
// See if the other type is an interface type of arrays.
if (ClassUtil.isInternalArrayInterfaceName(
ClassUtil.internalClassNameFromClassType(otherType))) {
return typedReferenceValue(other, mayBeNull);
}
} else if (thisDimensionCount < otherDimensionCount) {
// See if this type is an interface type of arrays.
if (ClassUtil.isInternalArrayInterfaceName(
ClassUtil.internalClassNameFromClassType(thisType))) {
return typedReferenceValue(this, mayBeNull);
}
}
// Reduce the common dimension count if either type is an array of
// primitives type of this dimension.
if (commonDimensionCount > 0
&& (ClassUtil.isInternalPrimitiveType(otherType.charAt(commonDimensionCount)))
|| ClassUtil.isInternalPrimitiveType(thisType.charAt(commonDimensionCount))) {
commonDimensionCount--;
}
// Fall back on a basic Object or array of Objects type.
return commonDimensionCount != 0
? new TypedReferenceValue(
ClassUtil.internalArrayTypeFromClassName(
ClassConstants.NAME_JAVA_LANG_OBJECT, commonDimensionCount),
null,
mayBeNull)
: mayBeNull
? ValueFactory.REFERENCE_VALUE_JAVA_LANG_OBJECT_MAYBE_NULL
: ValueFactory.REFERENCE_VALUE_JAVA_LANG_OBJECT_NOT_NULL;
}