java 解决全站字符乱码（POST和GET中文编码问题）

1建立个过滤器

package cn.itcast.web.filter;

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;

public class EncodingFilter implements Filter {
public void destroy() {

}

public void doFilter(ServletRequest request, ServletResponse response,
FilterChain chain) throws IOException, ServletException {
// 处理post请求编码问题
request.setCharacterEncoding("utf-8");

HttpServletRequest req = (HttpServletRequest) request;

/*
* 处理GET请求的编码问题
*/
// String username = request.getParameter("username");
// username = new String(username.getBytes("ISO-8859-1"), "UTF-8");

/*
* 调包request
* 1. 写一个request的装饰类
* 2. 在放行时，使用我们自己的request
*/
if(req.getMethod().equals("GET")) {
EncodingRequest er = new EncodingRequest(req);
chain.doFilter(er, response);
} else if(req.getMethod().equals("POST")) {
chain.doFilter(request, response);
}
}

public void init(FilterConfig fConfig) throws ServletException {

}
}
2.在web.xml配置过滤器
<filter>
<filter-name>EncodingFilter</filter-name>
<filter-class>cn.itcast.filter.EncodingFilter</filter-class>
<init-param>
<param-name>charset</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>EncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>3. EncodingRequest从写requset
package cn.itcast.web.filter;

import java.io.UnsupportedEncodingException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

/**
* 装饰reqeust
* @author cxf
*
*/
public class EncodingRequest extends HttpServletRequestWrapper {
private HttpServletRequest req;

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

public String getParameter(String name) {
String value = req.getParameter(name);

// 处理编码问题
try {
value = new String(value.getBytes("iso-8859-1"), "utf-8");
} catch (UnsupportedEncodingException e) {
throw new RuntimeException(e);
}

return value;
}
}