org.apache.camel.guice.inject.Injectors Maven / Gradle / Ivy
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* 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.camel.guice.inject;
import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.lang.reflect.Type;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.StringTokenizer;
import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.google.inject.AbstractModule;
import com.google.inject.Binding;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Key;
import com.google.inject.Module;
import com.google.inject.Provider;
import com.google.inject.Scope;
import com.google.inject.Singleton;
import com.google.inject.TypeLiteral;
import com.google.inject.internal.BindingImpl;
import com.google.inject.internal.Scoping;
import com.google.inject.matcher.Matcher;
import com.google.inject.name.Names;
import com.google.inject.util.Modules;
import org.apache.camel.guice.jndi.GuiceInitialContextFactory;
import org.apache.camel.guice.jndi.internal.Classes;
import org.apache.camel.guice.support.CloseErrors;
import org.apache.camel.guice.support.CloseFailedException;
import org.apache.camel.guice.support.Closer;
import org.apache.camel.guice.support.Closers;
import org.apache.camel.guice.support.CompositeCloser;
import org.apache.camel.guice.support.HasScopeAnnotation;
import org.apache.camel.guice.support.internal.CloseErrorsImpl;
@SuppressWarnings({ "rawtypes", "unchecked" })
public final class Injectors {
public static final String MODULE_CLASS_NAMES = "org.guiceyfruit.modules";
private Injectors() {
//Helper class
}
/**
* Creates an injector from the given properties, loading any modules define
* by the {@link #MODULE_CLASS_NAMES} property value (space separated) along
* with any other modules passed as an argument.
*
* @param environment
* the properties used to create the injector
* @param overridingModules
* any modules which override the modules referenced in the
* environment such as to provide the actual JNDI context
*/
public static Injector createInjector(final Map environment,
Module... overridingModules) throws ClassNotFoundException,
IllegalAccessException, InstantiationException {
List modules = Lists.newArrayList();
// lets bind the properties
modules.add(new AbstractModule() {
protected void configure() {
Names.bindProperties(binder(), environment);
}
});
Object moduleValue = environment.get(MODULE_CLASS_NAMES);
if (moduleValue instanceof String) {
String names = (String) moduleValue;
StringTokenizer iter = new StringTokenizer(names);
while (iter.hasMoreTokens()) {
String moduleName = iter.nextToken();
Module module = loadModule(moduleName);
if (module != null) {
modules.add(module);
}
}
}
Injector injector = Guice.createInjector(Modules.override(modules)
.with(overridingModules));
return injector;
}
/**
* Returns an instance of the given type with the
* {@link com.google.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;
}
protected static Module loadModule(String moduleName)
throws ClassNotFoundException, IllegalAccessException,
InstantiationException {
Class type = Classes.loadClass(moduleName,
GuiceInitialContextFactory.class.getClassLoader());
return (Module) type.newInstance();
}
/*
*/
/**
* Closes the given scope on this injector
*
* @param injector
* the injector on which to close objects
* @param scopeAnnotation
* the scope on which to close the objects
* @throws CloseFailedException
* the exceptions caused if closing an object fails
*/
/*
* public static void close(Injector injector, Annotation scopeAnnotation)
* throws CloseFailedException { Key key =
* Key.get(PreDestroyer.class, scopeAnnotation); if (hasBinding(injector,
* key)) { PreDestroyer destroyer = injector.getInstance(key);
* destroyer.close(); } }
*/
/**
* Closes any singleton objects in the injector using the currently
* registered {@link Closer} implementations
*/
public static void close(Injector injector) throws CloseFailedException {
close(injector, new CloseErrorsImpl(Injectors.class));
}
/**
* Closes objects within the given scope using the currently registered
* {@link Closer} implementations
*/
public static void close(Injector injector, CloseErrors errors)
throws CloseFailedException {
close(injector, Singleton.class, errors);
}
/**
* Closes objects within the given scope using the currently registered
* {@link Closer} implementations
*/
public static void close(Injector injector,
Class scopeAnnotationToClose)
throws CloseFailedException {
close(injector, scopeAnnotationToClose, new CloseErrorsImpl(
Injectors.class));
}
/**
* Closes objects within the given scope using the currently registered
* {@link Closer} implementations
*/
public static void close(Injector injector,
Class scopeAnnotationToClose,
CloseErrors errors) throws CloseFailedException {
Set closers = getInstancesOf(injector, Closer.class);
Closer closer = CompositeCloser.newInstance(closers);
if (closer == null) {
return;
}
Set, Binding>> entries = injector.getBindings()
.entrySet();
for (Entry, Binding> entry : entries) {
Key key = entry.getKey();
Binding binding = entry.getValue();
closeBinding(key, binding, scopeAnnotationToClose, closer, errors);
}
tryCloseJitBindings(closer, injector, scopeAnnotationToClose, errors);
errors.throwIfNecessary();
}
private static void tryCloseJitBindings(Closer closer, Injector injector,
Class scopeAnnotationToClose,
CloseErrors errors) {
Class type = injector.getClass();
Field field;
try {
field = type.getDeclaredField("jitBindings");
field.setAccessible(true);
Object bindings = field.get(injector);
if (bindings != null) {
if (bindings instanceof Map) {
Map, BindingImpl> map = (Map, BindingImpl>) bindings;
Set, BindingImpl>> entries = map.entrySet();
for (Entry, BindingImpl> entry : entries) {
closeBinding(entry.getKey(), entry.getValue(),
scopeAnnotationToClose, closer, errors);
}
}
}
} catch (NoSuchFieldException e) {
// ignore - Guice has refactored so we can't access the jit bindings
// System.out.println("No such field! " + e);
} catch (IllegalAccessException e) {
// ignore - Guice has refactored so we can't access the jit bindings
// System.out.println("Failed to access field: " + field +
// ". Reason: " + e);
}
}
private static void closeBinding(Key key, Binding binding,
Class scopeAnnotationToClose, Closer closer,
CloseErrors errors) {
Provider provider = binding.getProvider();
Class scopeAnnotation = getScopeAnnotation(binding);
if ((scopeAnnotation != null)
&& scopeAnnotation.equals(scopeAnnotationToClose)) {
Object value = provider.get();
if (value != null) {
Closers.close(key, value, closer, errors);
}
}
}
/**
* Returns the scope annotation for the given binding or null if there is no
* scope
*/
public static Class getScopeAnnotation(
Binding binding) {
Class scopeAnnotation = null;
if (binding instanceof BindingImpl) {
BindingImpl bindingImpl = (BindingImpl) binding;
Scoping scoping = bindingImpl.getScoping();
if (scoping != null) {
scopeAnnotation = scoping.getScopeAnnotation();
// TODO not sure why we need this hack???
if (scopeAnnotation == null) {
Scope scope = scoping.getScopeInstance();
if (scope instanceof HasScopeAnnotation) {
HasScopeAnnotation hasScopeAnnotation = (HasScopeAnnotation) scope;
scopeAnnotation = hasScopeAnnotation
.getScopeAnnotation();
}
if (scopeAnnotation == null
&& (scoping == Scoping.EAGER_SINGLETON
|| scoping == Scoping.SINGLETON_ANNOTATION || scoping == Scoping.SINGLETON_INSTANCE)) {
scopeAnnotation = Singleton.class;
}
}
}
}
return scopeAnnotation;
}
}
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