/*
* Copyright 2008 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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.inject.rebind.binding;
import com.google.gwt.inject.rebind.reflect.NoSourceNameException;
import com.google.gwt.inject.rebind.reflect.ReflectUtil;
import com.google.gwt.inject.rebind.util.InjectorMethod;
import com.google.gwt.inject.rebind.util.NameGenerator;
import com.google.gwt.inject.rebind.util.Preconditions;
import com.google.gwt.inject.rebind.util.SourceSnippet;
import com.google.gwt.inject.rebind.util.SourceSnippetBuilder;
import com.google.gwt.inject.rebind.util.SourceSnippets;
import com.google.inject.Key;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
/**
* Binding implementation that replaces one type with another.
*/
public class BindClassBinding extends AbstractBinding implements Binding {
private final Key<?> sourceClassKey;
private final Key<?> boundClassKey;
BindClassBinding(Key<?> boundClassKey, Key<?> sourceClassKey, Context context) {
// In which package should the creator method for a bind class binding be
// placed, when the bound class key (the "interface type") and the source
// class key (the "implementation type") might be in different packages, and
// one or both might be package-private?
//
// The answer is that it's always right to use the source class key to
// choose the creator's package. Consider these cases:
//
// 1) Both public: we can place the creator in any package.
//
// 2) boundClass private, sourceClass public: they must be in the same
// package, since sourceClass implements boundClass.
//
// 3) boundClass public, sourceClass private: we can create an instance of
// sourceClass only in its own package.
//
// 4) boundClass private, sourceClass private: again, they must be in the
// same package (and we have to create an instance of sourceClass from
// its own package).
super(context, sourceClassKey);
this.boundClassKey = Preconditions.checkNotNull(boundClassKey);
this.sourceClassKey = Preconditions.checkNotNull(sourceClassKey);
}
public SourceSnippet getCreationStatements(NameGenerator nameGenerator,
List<InjectorMethod> methodsOutput) throws NoSourceNameException {
String type = ReflectUtil.getSourceName(sourceClassKey.getTypeLiteral());
return new SourceSnippetBuilder()
.append(type).append(" result = ").append(SourceSnippets.callGetter(boundClassKey))
.append(";")
.build();
}
public Collection<Dependency> getDependencies() {
Context context = getContext();
Collection<Dependency> dependencies = new ArrayList<Dependency>();
dependencies.add(new Dependency(Dependency.GINJECTOR, sourceClassKey, context));
dependencies.add(new Dependency(sourceClassKey, boundClassKey, context));
return dependencies;
}
}