/*
* Copyright (C) 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.inject.servlet;
import com.google.common.collect.Lists;
import com.google.inject.Binding;
import com.google.inject.Inject;
import com.google.inject.Injector;
import com.google.inject.Singleton;
import com.google.inject.TypeLiteral;
import java.util.List;
/**
* A wrapping dispatcher for servlets, in much the same way as {@link ManagedFilterPipeline} is for
* filters.
*
* @author dhanji@gmail.com (Dhanji R. Prasanna)
*/
@Singleton
class ManagedServletPipeline extends AbstractServletPipeline {
private final ServletDefinition[] servletDefinitions;
private static final TypeLiteral<ServletDefinition> SERVLET_DEFS =
TypeLiteral.get(ServletDefinition.class);
@Inject
public ManagedServletPipeline(Injector injector) {
this.servletDefinitions = collectServletDefinitions(injector);
}
@Override
protected boolean hasServletsMapped() {
return servletDefinitions.length > 0;
}
@Override
protected ServletDefinition[] servletDefinitions() {
return servletDefinitions;
}
/**
* Introspects the injector and collects all instances of bound {@code List<ServletDefinition>}
* into a master list.
*
* <p>We have a guarantee that {@link com.google.inject.Injector#getBindings()} returns a map that
* preserves insertion order in entry-set iterators.
*/
private ServletDefinition[] collectServletDefinitions(Injector injector) {
List<ServletDefinition> servletDefinitions = Lists.newArrayList();
for (Binding<ServletDefinition> entry : injector.findBindingsByType(SERVLET_DEFS)) {
servletDefinitions.add(entry.getProvider().get());
}
// Copy to a fixed size array for speed.
return servletDefinitions.toArray(new ServletDefinition[servletDefinitions.size()]);
}
}