jsp+mysql的字符过滤器

jsp+mysql项目里面，在和数据库交互的时候，总是出现乱码。这都是老生常谈的事情了。

之前在那里放了一放，今天觉得还是尽早解决。用了一个过滤器。

代码：

package wang.util;

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 EncodeFilter implements Filter {

    private String requestEncoding="";
    private String responseEncoding=""; 

    public void destroy() {
        // TODO Auto-generated method stub
        System.out.println("字符编码过滤器销毁！");
    }

    public void doFilter(ServletRequest request, ServletResponse response,    FilterChain filterChain) throws IOException, ServletException {
        // TODO Auto-generated method stub
         System.out.println("编码过滤器运行中。。。");
         request.setCharacterEncoding(requestEncoding);
         response.setContentType(responseEncoding);
         filterChain.doFilter(request, response);

    }

    public void init(FilterConfig arg0) throws ServletException {
        // TODO Auto-generated method stub
         System.out.println("字符编码过滤器初始化！");
         requestEncoding=arg0.getInitParameter("requestEncoding");
         responseEncoding=arg0.getInitParameter("responseEncoding");
    }

}

然后，web.xml配置一下

<!-- 编码过滤器开始 -->
 <filter>
  <filter-name>filterEncoding</filter-name>
  <filter-class>wang.util.EncodeFilter</filter-class>
  <init-param>
   <param-name>requestEncoding</param-name>
   <param-value>utf-8</param-value>
  </init-param>
  <init-param>
   <param-name>responseEncoding</param-name>
   <param-value>text/html;charset=utf-8</param-value>
  </init-param>
 </filter>
 <filter-mapping>
  <filter-name>filterEncoding</filter-name>
  <url-pattern>/*</url-pattern>
 </filter-mapping>
<!-- 编码过滤器结束 -->
  

怕再出问题，于是就再干脆点，连接的地方，也设定编码

private String dbUrl="jdbc:mysql://localhost:3306/mycows?useUnicode=true&characterEncoding=utf-8";

然后一切ok，也省的在每个servlet里面设置编码了。