Java example source code file (InstanceBindingImpl.java)

This example Java source code file (InstanceBindingImpl.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

hasdependencies, immutableset, instancebindingimpl, internalfactory, key, object, override, provider, scoping, set, string, util

The InstanceBindingImpl.java Java example source code

/**
 * 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.internal;

import com.google.common.base.MoreObjects;
import com.google.common.base.Objects;
import com.google.common.collect.ImmutableSet;
import com.google.inject.Binder;
import com.google.inject.Key;
import com.google.inject.Provider;
import com.google.inject.spi.BindingTargetVisitor;
import com.google.inject.spi.Dependency;
import com.google.inject.spi.HasDependencies;
import com.google.inject.spi.InjectionPoint;
import com.google.inject.spi.InstanceBinding;
import com.google.inject.util.Providers;

import java.util.Set;

final class InstanceBindingImpl<T> extends BindingImpl implements InstanceBinding {

  final T instance;
  final Provider<T> provider;
  final ImmutableSet<InjectionPoint> injectionPoints;

  public InstanceBindingImpl(InjectorImpl injector, Key<T> key, Object source,
      InternalFactory<? extends T> internalFactory, Set injectionPoints,
      T instance) {
    super(injector, key, source, internalFactory, Scoping.EAGER_SINGLETON);
    this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
    this.instance = instance;
    this.provider = Providers.of(instance);
  }

  public InstanceBindingImpl(Object source, Key<T> key, Scoping scoping,
      Set<InjectionPoint> injectionPoints, T instance) {
    super(source, key, scoping);
    this.injectionPoints = ImmutableSet.copyOf(injectionPoints);
    this.instance = instance;
    this.provider = Providers.of(instance);
  }

  @Override public Provider<T> getProvider() {
    return this.provider;
  }

  public <V> V acceptTargetVisitor(BindingTargetVisitor visitor) {
    return visitor.visit(this);
  }

  public T getInstance() {
    return instance;
  }

  public Set<InjectionPoint> getInjectionPoints() {
    return injectionPoints;
  }

  public Set<Dependency getDependencies() {
    return instance instanceof HasDependencies
        ? ImmutableSet.copyOf(((HasDependencies) instance).getDependencies())
        : Dependency.forInjectionPoints(injectionPoints);
  }

  public BindingImpl<T> withScoping(Scoping scoping) {
    return new InstanceBindingImpl<T>(getSource(), getKey(), scoping, injectionPoints, instance);
  }

  public BindingImpl<T> withKey(Key key) {
    return new InstanceBindingImpl<T>(getSource(), key, getScoping(), injectionPoints, instance);
  }

  public void applyTo(Binder binder) {
    // instance bindings aren't scoped
    binder.withSource(getSource()).bind(getKey()).toInstance(instance);
  }

  @Override public String toString() {
    return MoreObjects.toStringHelper(InstanceBinding.class)
        .add("key", getKey())
        .add("source", getSource())
        .add("instance", instance)
        .toString();
  }

  @Override
  public boolean equals(Object obj) {
    if(obj instanceof InstanceBindingImpl) {
      InstanceBindingImpl<?> o = (InstanceBindingImpl)obj;
      return getKey().equals(o.getKey())
        && getScoping().equals(o.getScoping())
        && Objects.equal(instance, o.instance);
    } else {
      return false;
    }
  }

  @Override
  public int hashCode() {
    return Objects.hashCode(getKey(), getScoping());
  }
}