JSP中文乱码处理（过滤器）

SetEncodingFilter．java

package cn.cmpy.publicinfo;

/**
* @author Administrator
* 过滤器，转码
*/
import javax.servlet.Filter;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.FilterChain;
import java.io.IOException;

public class SetEncodingFilter implements Filter {
protected String encoding = null;
/**
* The filter configuration object we are associated with. If this value
* is null, this filter instance is not currently configured.
*/
protected FilterConfig filterConfig = null;

/**
* Should a character encoding specified by the client be ignored?
*/
protected boolean ignore = true;

/**
* Take this filter out of service.
*/
public void destroy() {
this.encoding = null;
this.filterConfig = null;
}

/**
* Select and set (if specified) the character encoding to be used to
* interpret request parameters for this request.
*
* @param request The servlet request we are processing
* @param result The servlet response we are creating
* @param chain The filter chain we are processing
*
* @exception IOException if an input/output error occurs
* @exception ServletException if a servlet error occurs
*/
public void doFilter(
ServletRequest request,
ServletResponse response,
FilterChain chain) throws IOException, ServletException {
if(ignore || (request.getCharacterEncoding() == null)) {
request.setCharacterEncoding(selectEncoding(request));
}
chain.doFilter(request, response);
}

/**
* Place this filter into service.
* @param filterConfig The filter configuration object
*/
public void init(FilterConfig filterConfig) throws ServletException {
this.filterConfig = filterConfig;
this.encoding = filterConfig.getInitParameter("encoding");
String value = filterConfig.getInitParameter("ignore");
if (value == null)
this.ignore = true;
else if (value.equalsIgnoreCase("true") || value.equalsIgnoreCase("yes"))
this.ignore = true;
else
this.ignore = false;
}

protected String selectEncoding(ServletRequest request) {
return (this.encoding);
}

/**
* Returns the filterConfig.
* @return FilterConfig
*/
public FilterConfig getFilterConfig() {
return filterConfig;
}

/**
* Sets the filterConfig.
* @param filterConfig The filterConfig to set
*/
public void setFilterConfig(FilterConfig filterConfig) {
this.filterConfig = filterConfig;
}

}
web.xml配置:

<filter>
<filter-name>EncodingFilter</filter-name>
<filter-class>cn.cmpy.publicinfo.SetEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>GBK</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>EncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>