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/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.common.inject;
import com.google.common.collect.Sets;
import org.elasticsearch.common.inject.matcher.Matcher;
import org.elasticsearch.common.inject.name.Names;
import org.elasticsearch.common.inject.spi.Message;
import java.lang.reflect.Type;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
/**
*
*/
public class Injectors {
public static Throwable getFirstErrorFailure(CreationException e) {
if (e.getErrorMessages().isEmpty()) {
return e;
}
// return the first message that has root cause, probably an actual error
for (Message message : e.getErrorMessages()) {
if (message.getCause() != null) {
return message.getCause();
}
}
return e;
}
/**
* Returns an instance of the given type with the {@link org.elasticsearch.common.inject.name.Named}
* annotation value.
*
* This method allows you to switch this code
* injector.getInstance(Key.get(type, Names.named(name)));
*
* to the more concise
* Injectors.getInstance(injector, type, name);
*/
public static T getInstance(Injector injector, java.lang.Class type, String name) {
return injector.getInstance(Key.get(type, Names.named(name)));
}
/**
* Returns a collection of all instances of the given base type
*
* @param baseClass the base type of objects required
* @param the base type
* @return a set of objects returned from this injector
*/
public static Set getInstancesOf(Injector injector, Class baseClass) {
Set answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && baseClass.isAssignableFrom(keyType)) {
Binding binding = entry.getValue();
Object value = binding.getProvider().get();
if (value != null) {
T castValue = baseClass.cast(value);
answer.add(castValue);
}
}
}
return answer;
}
/**
* Returns a collection of all instances matching the given matcher
*
* @param matcher matches the types to return instances
* @return a set of objects returned from this injector
*/
public static Set getInstancesOf(Injector injector, Matcher matcher) {
Set answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && matcher.matches(keyType)) {
Binding binding = entry.getValue();
Object value = binding.getProvider().get();
answer.add((T) value);
}
}
return answer;
}
/**
* Returns a collection of all of the providers matching the given matcher
*
* @param matcher matches the types to return instances
* @return a set of objects returned from this injector
*/
public static Set> getProvidersOf(Injector injector, Matcher matcher) {
Set> answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && matcher.matches(keyType)) {
Binding binding = entry.getValue();
answer.add((Provider) binding.getProvider());
}
}
return answer;
}
/**
* Returns a collection of all providers of the given base type
*
* @param baseClass the base type of objects required
* @param the base type
* @return a set of objects returned from this injector
*/
public static Set> getProvidersOf(Injector injector, Class baseClass) {
Set> answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && baseClass.isAssignableFrom(keyType)) {
Binding binding = entry.getValue();
answer.add((Provider) binding.getProvider());
}
}
return answer;
}
/**
* Returns true if a binding exists for the given matcher
*/
public static boolean hasBinding(Injector injector, Matcher matcher) {
return !getBindingsOf(injector, matcher).isEmpty();
}
/**
* Returns true if a binding exists for the given base class
*/
public static boolean hasBinding(Injector injector, Class baseClass) {
return !getBindingsOf(injector, baseClass).isEmpty();
}
/**
* Returns true if a binding exists for the given key
*/
public static boolean hasBinding(Injector injector, Key key) {
Binding binding = getBinding(injector, key);
return binding != null;
}
/**
* Returns the binding for the given key or null if there is no such binding
*/
public static Binding getBinding(Injector injector, Key key) {
Map, Binding> bindings = injector.getBindings();
Binding binding = bindings.get(key);
return binding;
}
/**
* Returns a collection of all of the bindings matching the given matcher
*
* @param matcher matches the types to return instances
* @return a set of objects returned from this injector
*/
public static Set> getBindingsOf(Injector injector, Matcher matcher) {
Set> answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && matcher.matches(keyType)) {
answer.add(entry.getValue());
}
}
return answer;
}
/**
* Returns a collection of all bindings of the given base type
*
* @param baseClass the base type of objects required
* @return a set of objects returned from this injector
*/
public static Set> getBindingsOf(Injector injector, Class baseClass) {
Set> answer = Sets.newHashSet();
Set, Binding>> entries = injector.getBindings().entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Class keyType = getKeyType(key);
if (keyType != null && baseClass.isAssignableFrom(keyType)) {
answer.add(entry.getValue());
}
}
return answer;
}
/**
* Returns the key type of the given key
*/
public static Class getKeyType(Key key) {
Class keyType = null;
TypeLiteral typeLiteral = key.getTypeLiteral();
Type type = typeLiteral.getType();
if (type instanceof Class) {
keyType = (Class) type;
}
return keyType;
}
public static void cleanCaches(Injector injector) {
((InjectorImpl) injector).clearCache();
if (injector.getParent() != null) {
cleanCaches(injector.getParent());
}
}
}