1/**
2 * Copyright (C) 2008 Google Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.google.inject.internal;
18
19import com.google.inject.spi.DefaultElementVisitor;
20import com.google.inject.spi.Element;
21
22import java.util.Iterator;
23import java.util.List;
24
25/**
26 * Abstract base class for creating an injector from module elements.
27 *
28 * <p>Extending classes must return {@code true} from any overridden
29 * {@code visit*()} methods, in order for the element processor to remove the
30 * handled element.
31 *
32 * @author jessewilson@google.com (Jesse Wilson)
33 */
34abstract class AbstractProcessor extends DefaultElementVisitor<Boolean> {
35
36  protected Errors errors;
37  protected InjectorImpl injector;
38
39  protected AbstractProcessor(Errors errors) {
40    this.errors = errors;
41  }
42
43  public void process(Iterable<InjectorShell> isolatedInjectorBuilders) {
44    for (InjectorShell injectorShell : isolatedInjectorBuilders) {
45      process(injectorShell.getInjector(), injectorShell.getElements());
46    }
47  }
48
49  public void process(InjectorImpl injector, List<Element> elements) {
50    Errors errorsAnyElement = this.errors;
51    this.injector = injector;
52    try {
53      for (Iterator<Element> i = elements.iterator(); i.hasNext(); ) {
54        Element element = i.next();
55        this.errors = errorsAnyElement.withSource(element.getSource());
56        Boolean allDone = element.acceptVisitor(this);
57        if (allDone) {
58          i.remove();
59        }
60      }
61    } finally {
62      this.errors = errorsAnyElement;
63      this.injector = null;
64    }
65  }
66
67  @Override
68  protected Boolean visitOther(Element element) {
69    return false;
70  }
71}
72