/*
* Copyright (c) 2003, 2004, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
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package sun.reflect.generics.repository;
import java.lang.reflect.TypeVariable;
import sun.reflect.generics.factory.GenericsFactory;
import sun.reflect.generics.tree.FormalTypeParameter;
import sun.reflect.generics.tree.Signature;
import sun.reflect.generics.visitor.Reifier;
/**
* This class represents the generic type information for a generic
* declaration.
* The code is not dependent on a particular reflective implementation.
* It is designed to be used unchanged by at least core reflection and JDI.
*/
public abstract class GenericDeclRepository<S extends Signature>
extends AbstractRepository<S> {
private TypeVariable[] typeParams; // caches the formal type parameters
protected GenericDeclRepository(String rawSig, GenericsFactory f) {
super(rawSig, f);
}
// public API
/*
* When queried for a particular piece of type information, the
* general pattern is to consult the corresponding cached value.
* If the corresponding field is non-null, it is returned.
* If not, it is created lazily. This is done by selecting the appropriate
* part of the tree and transforming it into a reflective object
* using a visitor.
* a visitor, which is created by feeding it the factory
* with which the repository was created.
*/
/**
* Return the formal type parameters of this generic declaration.
* @return the formal type parameters of this generic declaration
*/
public TypeVariable/*<?>*/[] getTypeParameters(){
if (typeParams == null) { // lazily initialize type parameters
// first, extract type parameter subtree(s) from AST
FormalTypeParameter[] ftps = getTree().getFormalTypeParameters();
// create array to store reified subtree(s)
TypeVariable[] tps = new TypeVariable[ftps.length];
// reify all subtrees
for (int i = 0; i < ftps.length; i++) {
Reifier r = getReifier(); // obtain visitor
ftps[i].accept(r); // reify subtree
// extract result from visitor and store it
tps[i] = (TypeVariable<?>) r.getResult();
}
typeParams = tps; // cache overall result
}
return typeParams.clone(); // return cached result
}
}