/*
* 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 org.elasticsearch.common.inject;
import org.elasticsearch.common.inject.internal.Errors;
import org.elasticsearch.common.inject.internal.ErrorsException;
import org.elasticsearch.common.inject.internal.InternalContext;
import org.elasticsearch.common.inject.internal.InternalFactory;
import org.elasticsearch.common.inject.internal.PrivateElementsImpl;
import org.elasticsearch.common.inject.internal.ProviderInstanceBindingImpl;
import org.elasticsearch.common.inject.internal.Scoping;
import org.elasticsearch.common.inject.internal.SourceProvider;
import org.elasticsearch.common.inject.internal.Stopwatch;
import org.elasticsearch.common.inject.spi.Dependency;
import org.elasticsearch.common.inject.spi.Element;
import org.elasticsearch.common.inject.spi.Elements;
import org.elasticsearch.common.inject.spi.InjectionPoint;
import org.elasticsearch.common.inject.spi.PrivateElements;
import org.elasticsearch.common.inject.spi.TypeListenerBinding;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import java.util.logging.Logger;
import static java.util.Collections.emptySet;
import static org.elasticsearch.common.inject.Scopes.SINGLETON;
/**
* A partially-initialized injector. See {@link InjectorBuilder}, which uses this to build a tree
* of injectors in batch.
*
* @author jessewilson@google.com (Jesse Wilson)
*/
class InjectorShell {
private final List<Element> elements;
private final InjectorImpl injector;
private InjectorShell(List<Element> elements, InjectorImpl injector) {
this.elements = elements;
this.injector = injector;
}
InjectorImpl getInjector() {
return injector;
}
List<Element> getElements() {
return elements;
}
static class Builder {
private final List<Element> elements = new ArrayList<>();
private final List<Module> modules = new ArrayList<>();
/**
* lazily constructed
*/
private State state;
private InjectorImpl parent;
private Stage stage;
/**
* null unless this exists in a {@link Binder#newPrivateBinder private environment}
*/
private PrivateElementsImpl privateElements;
Builder parent(InjectorImpl parent) {
this.parent = parent;
this.state = new InheritingState(parent.state);
return this;
}
Builder stage(Stage stage) {
this.stage = stage;
return this;
}
Builder privateElements(PrivateElements privateElements) {
this.privateElements = (PrivateElementsImpl) privateElements;
this.elements.addAll(privateElements.getElements());
return this;
}
void addModules(Iterable<? extends Module> modules) {
for (Module module : modules) {
this.modules.add(module);
}
}
/**
* Synchronize on this before calling {@link #build}.
*/
Object lock() {
return getState().lock();
}
/**
* Creates and returns the injector shells for the current modules. Multiple shells will be
* returned if any modules contain {@link Binder#newPrivateBinder private environments}. The
* primary injector will be first in the returned list.
*/
List<InjectorShell> build(Initializer initializer, BindingProcessor bindingProcessor,
Stopwatch stopwatch, Errors errors) {
if (stage == null) {
throw new IllegalStateException("Stage not initialized");
}
if (privateElements != null && parent == null) {
throw new IllegalStateException("PrivateElements with no parent");
}
if (state == null) {
throw new IllegalStateException("no state. Did you remember to lock() ?");
}
InjectorImpl injector = new InjectorImpl(state, initializer);
if (privateElements != null) {
privateElements.initInjector(injector);
}
// bind Stage and Singleton if this is a top-level injector
if (parent == null) {
modules.add(0, new RootModule(stage));
new TypeConverterBindingProcessor(errors).prepareBuiltInConverters(injector);
}
elements.addAll(Elements.getElements(stage, modules));
stopwatch.resetAndLog("Module execution");
new MessageProcessor(errors).process(injector, elements);
new TypeListenerBindingProcessor(errors).process(injector, elements);
List<TypeListenerBinding> listenerBindings = injector.state.getTypeListenerBindings();
injector.membersInjectorStore = new MembersInjectorStore(injector, listenerBindings);
stopwatch.resetAndLog("TypeListeners creation");
new ScopeBindingProcessor(errors).process(injector, elements);
stopwatch.resetAndLog("Scopes creation");
new TypeConverterBindingProcessor(errors).process(injector, elements);
stopwatch.resetAndLog("Converters creation");
bindInjector(injector);
bindLogger(injector);
bindingProcessor.process(injector, elements);
stopwatch.resetAndLog("Binding creation");
List<InjectorShell> injectorShells = new ArrayList<>();
injectorShells.add(new InjectorShell(elements, injector));
// recursively build child shells
PrivateElementProcessor processor = new PrivateElementProcessor(errors, stage);
processor.process(injector, elements);
for (Builder builder : processor.getInjectorShellBuilders()) {
injectorShells.addAll(builder.build(initializer, bindingProcessor, stopwatch, errors));
}
stopwatch.resetAndLog("Private environment creation");
return injectorShells;
}
private State getState() {
if (state == null) {
state = new InheritingState(State.NONE);
}
return state;
}
}
/**
* The Injector is a special case because we allow both parent and child injectors to both have
* a binding for that key.
*/
private static void bindInjector(InjectorImpl injector) {
Key<Injector> key = Key.get(Injector.class);
InjectorFactory injectorFactory = new InjectorFactory(injector);
injector.state.putBinding(key,
new ProviderInstanceBindingImpl<>(injector, key, SourceProvider.UNKNOWN_SOURCE,
injectorFactory, Scoping.UNSCOPED, injectorFactory,
emptySet()));
}
private static class InjectorFactory implements InternalFactory<Injector>, Provider<Injector> {
private final Injector injector;
private InjectorFactory(Injector injector) {
this.injector = injector;
}
@Override
public Injector get(Errors errors, InternalContext context, Dependency<?> dependency)
throws ErrorsException {
return injector;
}
@Override
public Injector get() {
return injector;
}
@Override
public String toString() {
return "Provider<Injector>";
}
}
/**
* The Logger is a special case because it knows the injection point of the injected member. It's
* the only binding that does this.
*/
private static void bindLogger(InjectorImpl injector) {
Key<Logger> key = Key.get(Logger.class);
LoggerFactory loggerFactory = new LoggerFactory();
injector.state.putBinding(key,
new ProviderInstanceBindingImpl<>(injector, key,
SourceProvider.UNKNOWN_SOURCE, loggerFactory, Scoping.UNSCOPED,
loggerFactory, emptySet()));
}
private static class LoggerFactory implements InternalFactory<Logger>, Provider<Logger> {
@Override
public Logger get(Errors errors, InternalContext context, Dependency<?> dependency) {
InjectionPoint injectionPoint = dependency.getInjectionPoint();
return injectionPoint == null
? Logger.getAnonymousLogger()
: Logger.getLogger(injectionPoint.getMember().getDeclaringClass().getName());
}
@Override
public Logger get() {
return Logger.getAnonymousLogger();
}
@Override
public String toString() {
return "Provider<Logger>";
}
}
private static class RootModule implements Module {
final Stage stage;
private RootModule(Stage stage) {
this.stage = Objects.requireNonNull(stage, "stage");
}
@Override
public void configure(Binder binder) {
binder = binder.withSource(SourceProvider.UNKNOWN_SOURCE);
binder.bind(Stage.class).toInstance(stage);
binder.bindScope(Singleton.class, SINGLETON);
}
}
}