/**
* Establishes the type bound:
*
* <ol>
* <li>{@code<? extends Number>}, returns Number
* <li>{@code<? super Number>}, returns Number
* <li>{@code<?>}, returns Object
* <li>{@code<T extends Number>, returns Number}
* </ol>
*
* @param typeMirror the type to return the bound for
* @return the bound for this parameter
*/
public TypeMirror getTypeBound(TypeMirror typeMirror) {
if (typeMirror.getKind() == TypeKind.WILDCARD) {
WildcardType wildCardType = (WildcardType) typeMirror;
if (wildCardType.getExtendsBound() != null) {
return wildCardType.getExtendsBound();
}
if (wildCardType.getSuperBound() != null) {
return wildCardType.getSuperBound();
}
String wildCardName = wildCardType.toString();
if ("?".equals(wildCardName)) {
return elementUtils.getTypeElement(Object.class.getCanonicalName()).asType();
}
} else if (typeMirror.getKind() == TypeKind.TYPEVAR) {
TypeVariable typeVariableType = (TypeVariable) typeMirror;
if (typeVariableType.getUpperBound() != null) {
return typeVariableType.getUpperBound();
}
// Lowerbounds intentionally left out: Type variables otherwise have a lower bound of
// NullType.
}
return typeMirror;
}
@Override
public JsonType visitWildcard(WildcardType wildcardType, Void o) {
throw new UnsupportedOperationException(wildcardType.toString());
}