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1
16
17 package com.google.inject.servlet;
18
19 import java.io.IOException  ;
20
21 import javax.servlet.Filter ;
22 import javax.servlet.FilterChain ;
23 import javax.servlet.FilterConfig ;
24 import javax.servlet.ServletException ;
25 import javax.servlet.ServletRequest ;
26 import javax.servlet.ServletResponse ;
27 import javax.servlet.http.HttpServletRequest ;
28 import javax.servlet.http.HttpServletResponse ;
29
30
35 public class GuiceFilter implements Filter {
36
37 static final ThreadLocal <Context> localContext = new ThreadLocal <Context>();
38
39 public void doFilter(ServletRequest servletRequest,
40 ServletResponse servletResponse, FilterChain filterChain)
41 throws IOException , ServletException {
42 Context previous = localContext.get();
43 try {
44 localContext.set(new Context((HttpServletRequest ) servletRequest,
45 (HttpServletResponse ) servletResponse));
46 filterChain.doFilter(servletRequest, servletResponse);
47 } finally {
48 localContext.set(previous);
49 }
50 }
51
52 static HttpServletRequest getRequest() {
53 return getContext().getRequest();
54 }
55
56 static HttpServletResponse getResponse() {
57 return getContext().getResponse();
58 }
59
60 static Context getContext() {
61 Context context = localContext.get();
62 if (context == null) {
63 throw new RuntimeException ("Please apply " + GuiceFilter.class.getName()
64 + " to any request which uses servlet scopes.");
65 }
66 return context;
67 }
68
69 static class Context {
70
71 final HttpServletRequest request;
72 final HttpServletResponse response;
73
74 Context(HttpServletRequest request, HttpServletResponse response) {
75 this.request = request;
76 this.response = response;
77 }
78
79 HttpServletRequest getRequest() {
80 return request;
81 }
82
83 HttpServletResponse getResponse() {
84 return response;
85 }
86 }
87
88 public void init(FilterConfig filterConfig) throws ServletException {}
89
90 public void destroy() {}
91 }
92 |
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