main/java/TestFilter.java



import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;


/**
 * Servlet Filter implementation class TestFilter
 */
public class TestFilter implements Filter {
        
        class CustomRequest extends HttpServletRequestWrapper {

                HttpServletRequest request;
                
                public CustomRequest(HttpServletRequest request) {
                        super(request);
                        this.request = request;
                }

                
                @Override
                public String getRemoteAddr() {
                        String header = request.getHeader("x-forwarded-for"); 
                        if ( header != null) {
                                return header;
                        } else {
                                return request.getRemoteAddr();
                        }
                }

                @Override
                public String getRemoteHost() {
                        return getRemoteAddr();
                }

                
        }

    /**
     * Default constructor. 
     */
    public TestFilter() {
        // TODO Auto-generated constructor stub
    }

        /**
         * @see Filter#destroy()
         */
        public void destroy() {
                // TODO Auto-generated method stub
        }

        /**
         * @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
         */
        public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {

                HttpServletRequest req = (HttpServletRequest) request;
                
                chain.doFilter(new CustomRequest(req), response);
        }

        /**
         * @see Filter#init(FilterConfig)
         */
        public void init(FilterConfig fConfig) throws ServletException {
                // TODO Auto-generated method stub
        }

}
1
2
3	import java.io.IOException;
4
5	import javax.servlet.Filter;
6	import javax.servlet.FilterChain;
7	import javax.servlet.FilterConfig;
8	import javax.servlet.ServletException;
9	import javax.servlet.ServletRequest;
10	import javax.servlet.ServletResponse;
11	import javax.servlet.http.HttpServletRequest;
12	import javax.servlet.http.HttpServletRequestWrapper;
13
14
15	/**
16	* Servlet Filter implementation class TestFilter
17	*/
18	public class TestFilter implements Filter {
19
20	class CustomRequest extends HttpServletRequestWrapper {
21
22	HttpServletRequest request;
23
24	public CustomRequest(HttpServletRequest request) {
25	super(request);
26	this.request = request;
27	}
28
29
30	@Override
31	public String getRemoteAddr() {
32	String header = request.getHeader("x-forwarded-for");
33	if ( header != null) {
34	return header;
35	} else {
36	return request.getRemoteAddr();
37	}
38	}
39
40	@Override
41	public String getRemoteHost() {
42	return getRemoteAddr();
43	}
44
45
46	}
47
48	/**
49	* Default constructor.
50	*/
51	public TestFilter() {
52	// TODO Auto-generated constructor stub
53	}
54
55	/**
56	* @see Filter#destroy()
57	*/
58	public void destroy() {
59	// TODO Auto-generated method stub
60	}
61
62	/**
63	* @see Filter#doFilter(ServletRequest, ServletResponse, FilterChain)
64	*/
65	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
66
67	HttpServletRequest req = (HttpServletRequest) request;
68
69	chain.doFilter(new CustomRequest(req), response);
70	}
71
72	/**
73	* @see Filter#init(FilterConfig)
74	*/
75	public void init(FilterConfig fConfig) throws ServletException {
76	// TODO Auto-generated method stub
77	}
78
79	}