/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.shiro.guice.web;
import com.google.common.collect.ImmutableSet;
import com.google.inject.Inject;
import com.google.inject.Injector;
import com.google.inject.Key;
import com.google.inject.ProvisionException;
import com.google.inject.spi.Dependency;
import com.google.inject.spi.InjectionPoint;
import com.google.inject.spi.ProviderWithDependencies;
import java.lang.reflect.Constructor;
import java.util.Set;
class AbstractInjectionProvider<T> implements ProviderWithDependencies<T> {
private Key<T> key;
@Inject
Injector injector;
private InjectionPoint constructorInjectionPoint;
private Set<Dependency<?>> dependencies;
public AbstractInjectionProvider(Key<T> key) {
this.key = key;
constructorInjectionPoint = InjectionPoint.forConstructorOf(key.getTypeLiteral());
ImmutableSet.Builder<Dependency<?>> dependencyBuilder = ImmutableSet.builder();
dependencyBuilder.addAll(constructorInjectionPoint.getDependencies());
for (InjectionPoint injectionPoint : InjectionPoint.forInstanceMethodsAndFields(key.getTypeLiteral())) {
dependencyBuilder.addAll(injectionPoint.getDependencies());
}
this.dependencies = dependencyBuilder.build();
}
public T get() {
Constructor<T> constructor = getConstructor();
Object[] params = new Object[constructor.getParameterTypes().length];
for (Dependency<?> dependency : constructorInjectionPoint.getDependencies()) {
params[dependency.getParameterIndex()] = injector.getInstance(dependency.getKey());
}
T t;
try {
t = constructor.newInstance(params);
} catch (Exception e) {
throw new ProvisionException("Could not instantiate " + key + "", e);
}
injector.injectMembers(t);
return postProcess(t);
}
@SuppressWarnings({"unchecked"})
private Constructor<T> getConstructor() {
return (Constructor<T>) constructorInjectionPoint.getMember();
}
protected T postProcess(T t) {
// do nothing by default
return t;
}
public Set<Dependency<?>> getDependencies() {
return dependencies;
}
}