利用过滤器filter解决乱码问题

package org.dys.myznt.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;

public class EncodingFilter implements Filter {

private String charset = null;
public void destroy() {

}

public void doFilter(ServletRequest req, ServletResponse resp,
FilterChain chain) throws IOException, ServletException {
req.setCharacterEncoding(this.charset);
chain.doFilter(req, resp);
}

public void init(FilterConfig arg0) throws ServletException {
this.charset = arg0.getInitParameter("charset");
}

}

<!-- 加过滤器解决乱码问题 -->
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.dys.myznt.filter.EncodingFilter</filter-class>
<init-param>
<param-name>charset</param-name>
<param-value>GBK</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- 过滤器结束 -->