/*******************************************************************************
* Copyright 2011 Google Inc. All Rights Reserved.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*******************************************************************************/
package com.google.gwt.dev.javac;
import com.google.gwt.core.ext.typeinfo.JClassType;
import com.google.gwt.core.ext.typeinfo.JGenericType;
import com.google.gwt.core.ext.typeinfo.JTypeParameter;
import com.google.gwt.dev.util.collect.HashMap;
import com.google.gwt.dev.util.collect.Maps;
import java.util.LinkedList;
import java.util.Map;
/**
* Handles lookup of type parameters, using a scope stack.
*/
public class TypeParameterLookup {
private LinkedList<Map<String, JTypeParameter>> scopeStack = new LinkedList<Map<String, JTypeParameter>>();
public JTypeParameter lookup(String name) {
for (Map<String, JTypeParameter> scope : scopeStack) {
JTypeParameter result = scope.get(name);
if (result != null) {
return result;
}
}
return null;
}
public void popScope() {
scopeStack.remove();
}
public void pushEnclosingScopes(JClassType type) {
if (type == null) {
return;
}
pushEnclosingScopes(type.getEnclosingType());
JGenericType genericType = type.isGenericType();
if (genericType != null) {
pushScope(genericType.getTypeParameters());
}
}
public void pushScope(JTypeParameter[] typeParams) {
// push empty scopes to keep pops in sync
scopeStack.addFirst(buildScope(typeParams));
}
private Map<String, JTypeParameter> buildScope(JTypeParameter[] typeParams) {
switch (typeParams.length) {
case 0:
return Maps.create();
case 1:
return Maps.create(typeParams[0].getName(), typeParams[0]);
default:
Map<String, JTypeParameter> scope = new HashMap<String, JTypeParameter>();
for (JTypeParameter typeParam : typeParams) {
scope.put(typeParam.getName(), typeParam);
}
return scope;
}
}
}