使用Filter 设置编码简化Servlet的开发
1. 核心代码
package com.mscncn.jsd1404;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
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;
import javax.servlet.http.HttpServletResponse;
public class EncodingFilter implements Filter {
private static String encoding;
private static final String DEFAULT_CHARSET="UTF-8";
@Override
public void destroy() {
System.out.println("--------destroy---------");
}
@Override
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
System.out.println("--------doFilter---------");
HttpServletRequest httpRequest = (HttpServletRequest) request;
HttpServletResponse httpResponse=(HttpServletResponse)response;
if("GET".equals(httpRequest.getMethod())){
EncodingHttpServletRequest wrapper = new EncodingHttpServletRequest(httpRequest, encoding);
chain.doFilter(wrapper, response);
}else{
httpRequest.setCharacterEncoding(encoding);
httpResponse.setContentType("text/html;charset="+encoding);
}
}
private static class EncodingHttpServletRequest extends HttpServletRequestWrapper{
private HttpServletRequest request;
public EncodingHttpServletRequest(HttpServletRequest request,String encoding) {
super(request);
this.request = request;
}
@Override
public String getParameter(String name) {
String value = request.getParameter(name);
try {
value = new String(value.getBytes("iso8859-1"), encoding);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
return super.getParameter(name);
}
}
@Override
public void init(FilterConfig config) throws ServletException {
System.out.println("--------init---------");
encoding = config.getInitParameter("encoding");
if(encoding==null||"".equals(encoding))
encoding=DEFAULT_CHARSET;
}
}
2. web.xml 中得配置
characterFilter
com.mscncn.jsd1404.EncodingFilter
encoding
UTF-8
characterFilter
/*
原文：http://my.oschina.net/KingPan/blog/293268