| /* |
| * Copyright 2014 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.gwt.dev.util; |
| |
| import com.google.gwt.core.ext.TreeLogger; |
| import com.google.gwt.core.ext.UnableToCompleteException; |
| import com.google.gwt.thirdparty.guava.common.base.Preconditions; |
| |
| import java.io.Serializable; |
| |
| /** |
| * A Noop PersistentBackedObject that stores a reference to the data it's provided. Used only |
| * in per file compiles. |
| * <p> |
| * NOTE: Use this class with care as it does not provide a fresh deserialized copy of the data |
| * provided, |
| * |
| * @param <T> the type of object serialized into the file |
| */ |
| public class MemoryBackedObject<T extends Serializable> implements PersistenceBackedObject<T> { |
| |
| private T data; |
| private final Class<T> clazz; |
| |
| public MemoryBackedObject(Class<T> clazz) { |
| this.clazz = clazz; |
| } |
| |
| @Override |
| public boolean exists() { |
| return data != null; |
| } |
| |
| @Override |
| public String getPath() { |
| return null; |
| } |
| |
| @Override |
| public T newInstance(TreeLogger logger) throws UnableToCompleteException { |
| T result = data; |
| data = null; |
| return result; |
| } |
| |
| @Override |
| public void set(TreeLogger logger, T object) |
| throws IllegalStateException, UnableToCompleteException { |
| assert clazz.isInstance(object); |
| Preconditions.checkState(data == null); |
| data = object; |
| } |
| |
| @Override |
| public String toString() { |
| return "MemoryBackedObject" + "<" + clazz.getName() + ">"; |
| } |
| } |