摘要：
Servlet3.0作为J2EE 6规范一部分，并随J2EE6一起发布，WeFilter是过滤器注解，是Servlet3.0的新特性，不需要在web.xml进行配置，简化了配置。
|
Name |
Type |
Required |
Description |
|
filterName |
String |
Optional |
Name of the filter. |
|
value or urlPatterns |
String[] |
Required |
Specify one or more URL patterns to which the filter applies. Either of attribute can be used, but not both. |
|
dispatcherTypes |
DispatcherType[] |
Optional |
Specify types of dispatcher to which the filter applies. Default isjavax.servlet.DispatcherType.REQUEST |
|
servletNames |
String[] |
Optional |
Specify names of servlets to which the filter applies. |
|
displayName |
String |
Optional |
Display name of the filter. |
|
description |
String |
Optional |
Description of the filter. |
|
asyncSupported |
boolean |
Optional |
Specify whether the filter supports asynchronous operation mode. Default is false. |
|
initParams |
WebInitParam[] |
Optional |
Specify one or more initialization parameters of the filter. Each parameter is specified by@WebInitParamannotation type. |
|
smallIcon |
String |
Optional |
Specify name of the small icon of the filter. |
|
largeIcon |
String |
Optional |
Specify name of the large icon of the filter. |
OneFilter：
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package com.what21.servlet.webfilter;
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.annotation.WebFilter;
@WebFilter("/*")
public class OneFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("OneFilter doFilter()");
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
} |
TwoFilter：
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package com.what21.servlet.webfilter;
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.annotation.WebFilter;
@WebFilter(servletNames = "MyFourServlet")
public class TwoFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("TwoFilter doFilter()");
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
} |
ThreeFilter：
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package com.what21.servlet.webfilter;
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.annotation.WebFilter;
@WebFilter(servletNames = {"MyFourServlet", "MyFiveServlet"})
public class ThreeFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("ThreeFilter doFilter()");
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
} |
FourFilter：
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package com.what21.servlet.webfilter;
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.annotation.WebFilter;
@WebFilter({"/one","/two"})
public class FourFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("FourFilter doFilter()");
chain.doFilter(request, response);
}
@Override
public void destroy() {
}
} |
FiveFilter：
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package com.what21.servlet.webfilter;
import java.io.IOException;
import javax.servlet.DispatcherType;
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.annotation.WebFilter;
import javax.servlet.annotation.WebInitParam;
@WebFilter(
urlPatterns = "/five",
filterName = "FiveFilter",
initParams = {
@WebInitParam(name = "name", value = "username"),
@WebInitParam(name = "value", value = "password")
},
description = "MyFiveFilter",
dispatcherTypes = {DispatcherType.REQUEST, DispatcherType.FORWARD}
)public class FiveFilter implements Filter {
@Override
public void init(FilterConfig config) throws ServletException {
String name = config.getInitParameter("name");
String value = config.getInitParameter("value");
System.out.println("name = " + name);
System.out.println("value = " + value);
System.out.println("init().....");
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("FiveFilter doFilter()");
}
@Override
public void destroy() {
}
} |