/**
* Given a parameterized type and a generic type information, aligns actual type parameters. For
* example, if a class uses generic type
*
* <pre><T,U,V></pre>
*
* (redirectGenericTypes), is used with actual type parameters
*
* <pre><java.lang.String, U,V></pre>
*
* , then a class or interface using generic types
*
* <pre><T,V></pre>
*
* will be aligned to
*
* <pre><java.lang.String,V></pre>
*
* @param redirectGenericTypes the type arguments or the redirect class node
* @param parameterizedTypes the actual type arguments used on this class node
* @param alignmentTarget the generic type arguments to which we want to align to
* @return aligned type arguments
*/
public static GenericsType[] alignGenericTypes(
final GenericsType[] redirectGenericTypes,
final GenericsType[] parameterizedTypes,
final GenericsType[] alignmentTarget) {
if (alignmentTarget == null) return EMPTY_GENERICS_ARRAY;
if (parameterizedTypes == null || parameterizedTypes.length == 0) return alignmentTarget;
GenericsType[] generics = new GenericsType[alignmentTarget.length];
for (int i = 0, scgtLength = alignmentTarget.length; i < scgtLength; i++) {
final GenericsType currentTarget = alignmentTarget[i];
GenericsType match = null;
if (redirectGenericTypes != null) {
for (int j = 0; j < redirectGenericTypes.length && match == null; j++) {
GenericsType redirectGenericType = redirectGenericTypes[j];
if (redirectGenericType.isCompatibleWith(currentTarget.getType())) {
if (currentTarget.isPlaceholder()
&& redirectGenericType.isPlaceholder()
&& !currentTarget.getName().equals(redirectGenericType.getName())) {
// check if there's a potential better match
boolean skip = false;
for (int k = j + 1; k < redirectGenericTypes.length && !skip; k++) {
GenericsType ogt = redirectGenericTypes[k];
if (ogt.isPlaceholder()
&& ogt.isCompatibleWith(currentTarget.getType())
&& ogt.getName().equals(currentTarget.getName())) {
skip = true;
}
}
if (skip) continue;
}
match = parameterizedTypes[j];
if (currentTarget.isWildcard()) {
// if alignment target is a wildcard type
// then we must make best effort to return a parameterized
// wildcard
ClassNode lower = currentTarget.getLowerBound() != null ? match.getType() : null;
ClassNode[] currentUpper = currentTarget.getUpperBounds();
ClassNode[] upper = currentUpper != null ? new ClassNode[currentUpper.length] : null;
if (upper != null) {
for (int k = 0; k < upper.length; k++) {
upper[k] =
currentUpper[k].isGenericsPlaceHolder() ? match.getType() : currentUpper[k];
}
}
match = new GenericsType(ClassHelper.makeWithoutCaching("?"), upper, lower);
match.setWildcard(true);
}
}
}
}
if (match == null) {
match = currentTarget;
}
generics[i] = match;
}
return generics;
}
private String genericsBounds(ClassNode theType, Set<String> visited) {
String ret =
theType.isArray() ? theType.getComponentType().getName() + "[]" : theType.getName();
GenericsType[] genericsTypes = theType.getGenericsTypes();
if (genericsTypes == null || genericsTypes.length == 0) return ret;
// TODO instead of catching Object<T> here stop it from being placed into type in first place
if (genericsTypes.length == 1
&& genericsTypes[0].isPlaceholder()
&& theType.getName().equals("java.lang.Object")) {
return genericsTypes[0].getName();
}
ret += "<";
for (int i = 0; i < genericsTypes.length; i++) {
if (i != 0) ret += ", ";
GenericsType type = genericsTypes[i];
if (type.isPlaceholder() && visited.contains(type.getName())) {
ret += type.getName();
} else {
ret += type.toString(visited);
}
}
ret += ">";
return ret;
}
/**
* Interface class nodes retrieved from {@link org.codehaus.groovy.ast.ClassNode#getInterfaces()}
* or {@link org.codehaus.groovy.ast.ClassNode#getAllInterfaces()} are returned with generic type
* arguments. This method allows returning a parameterized interface given the parameterized class
* node which implements this interface.
*
* @param hint the class node where generics types are parameterized
* @param target the interface we want to parameterize generics types
* @return a parameterized interface class node
*/
public static ClassNode parameterizeType(final ClassNode hint, final ClassNode target) {
ClassNode interfaceFromClassNode = null;
if (hint.equals(target)) interfaceFromClassNode = hint;
if (ClassHelper.OBJECT_TYPE.equals(target)
&& target.isUsingGenerics()
&& target.getGenericsTypes() != null
&& target.getGenericsTypes()[0].isPlaceholder()) {
// Object<T>
return ClassHelper.getWrapper(hint);
}
if (interfaceFromClassNode == null) {
ClassNode[] interfaces = hint.getInterfaces();
for (ClassNode node : interfaces) {
if (node.equals(target)) {
interfaceFromClassNode = node;
break;
} else if (node.implementsInterface(target)) {
// ex: classNode = LinkedList<A> , node=List<E> , anInterface = Iterable<T>
return parameterizeType(parameterizeType(hint, node), target);
}
}
}
if (interfaceFromClassNode == null && hint.getUnresolvedSuperClass() != null) {
return parameterizeType(hint.getUnresolvedSuperClass(), target);
}
if (interfaceFromClassNode == null) {
// return target;
interfaceFromClassNode = hint;
}
Map<String, GenericsType> parameters = new HashMap<String, GenericsType>();
extractPlaceholders(hint, parameters);
ClassNode node = target.getPlainNodeReference();
GenericsType[] interfaceGTs = interfaceFromClassNode.getGenericsTypes();
if (interfaceGTs == null) return target;
GenericsType[] types = new GenericsType[interfaceGTs.length];
for (int i = 0; i < interfaceGTs.length; i++) {
GenericsType interfaceGT = interfaceGTs[i];
types[i] = interfaceGT;
if (interfaceGT.isPlaceholder()) {
String name = interfaceGT.getName();
if (parameters.containsKey(name)) {
types[i] = parameters.get(name);
}
}
}
node.setGenericsTypes(types);
return node;
}
/**
* For a given classnode, fills in the supplied map with the parameterized types it defines.
*
* @param node
* @param map
*/
public static void extractPlaceholders(ClassNode node, Map<String, GenericsType> map) {
if (node == null) return;
if (node.isArray()) {
extractPlaceholders(node.getComponentType(), map);
return;
}
if (!node.isUsingGenerics() || !node.isRedirectNode()) return;
GenericsType[] parameterized = node.getGenericsTypes();
if (parameterized == null || parameterized.length == 0) return;
GenericsType[] redirectGenericsTypes = node.redirect().getGenericsTypes();
if (redirectGenericsTypes == null) redirectGenericsTypes = parameterized;
for (int i = 0; i < redirectGenericsTypes.length; i++) {
GenericsType redirectType = redirectGenericsTypes[i];
if (redirectType.isPlaceholder()) {
String name = redirectType.getName();
if (!map.containsKey(name)) map.put(name, parameterized[i]);
}
}
}