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 */
16package com.google.inject.servlet;
17
18import com.google.common.collect.Sets;
19import com.google.inject.Binder;
20import com.google.inject.Key;
21import com.google.inject.internal.UniqueAnnotations;
22
23import java.util.HashMap;
24import java.util.List;
25import java.util.Map;
26import java.util.Set;
27
28import javax.servlet.http.HttpServlet;
29
30/**
31 * Builds the guice module that binds configured servlets, with their
32 * wrapper ServletDefinitions. Is part of the binding EDSL. Very similar to
33 * {@link com.google.inject.servlet.FiltersModuleBuilder}.
34 *
35 * @author Dhanji R. Prasanna (dhanji@gmail.com)
36 */
37class ServletsModuleBuilder {
38
39  private final Set<String> servletUris = Sets.newHashSet();
40  private final Binder binder;
41
42  public ServletsModuleBuilder(Binder binder) {
43    this.binder = binder;
44  }
45
46  //the first level of the EDSL--
47  public ServletModule.ServletKeyBindingBuilder serve(List<String> urlPatterns) {
48    return new ServletKeyBindingBuilderImpl(urlPatterns, UriPatternType.SERVLET);
49  }
50
51  public ServletModule.ServletKeyBindingBuilder serveRegex(List<String> regexes) {
52    return new ServletKeyBindingBuilderImpl(regexes, UriPatternType.REGEX);
53  }
54
55  //non-static inner class so it can access state of enclosing module class
56  class ServletKeyBindingBuilderImpl implements ServletModule.ServletKeyBindingBuilder {
57    private final List<String> uriPatterns;
58    private final UriPatternType uriPatternType;
59
60    private ServletKeyBindingBuilderImpl(List<String> uriPatterns, UriPatternType uriPatternType) {
61      this.uriPatterns = uriPatterns;
62      this.uriPatternType = uriPatternType;
63    }
64
65    public void with(Class<? extends HttpServlet> servletKey) {
66      with(Key.get(servletKey));
67    }
68
69    public void with(Key<? extends HttpServlet> servletKey) {
70      with(servletKey, new HashMap<String, String>());
71    }
72
73    public void with(HttpServlet servlet) {
74      with(servlet, new HashMap<String, String>());
75    }
76
77    public void with(Class<? extends HttpServlet> servletKey,
78        Map<String, String> initParams) {
79      with(Key.get(servletKey), initParams);
80    }
81
82    public void with(Key<? extends HttpServlet> servletKey,
83        Map<String, String> initParams) {
84      with(servletKey, initParams, null);
85    }
86
87    private void with(Key<? extends HttpServlet> servletKey, Map<String, String> initParams,
88        HttpServlet servletInstance) {
89      for (String pattern : uriPatterns) {
90        // Ensure two servlets aren't bound to the same pattern.
91        if (!servletUris.add(pattern)) {
92          binder.addError("More than one servlet was mapped to the same URI pattern: " + pattern);
93        } else {
94          binder.bind(Key.get(ServletDefinition.class, UniqueAnnotations.create())).toProvider(
95              new ServletDefinition(pattern, servletKey, UriPatternType
96                  .get(uriPatternType, pattern), initParams, servletInstance));
97        }
98      }
99    }
100
101    public void with(HttpServlet servlet,
102        Map<String, String> initParams) {
103      Key<HttpServlet> servletKey = Key.get(HttpServlet.class, UniqueAnnotations.create());
104      binder.bind(servletKey).toInstance(servlet);
105      with(servletKey, initParams, servlet);
106    }
107  }
108}
109