java 编码过滤器

public class SetCharacterEncodingFilter implements Filter {
	protected String encoding = null;
	protected FilterConfig filterConfig = null;
	protected boolean ignore = true;

	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"))
			this.ignore=true;
		else
			this.ignore=false;
	}

	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
		if (ignore || (request.getCharacterEncoding() == null)) {
			String encoding = selectEncoding(request);
		if (encoding != null)
			request.setCharacterEncoding(encoding);
		}
		chain.doFilter(request, response);
	}

	public void destroy() {
		this.encoding = null;
		this.filterConfig = null;
	}

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

web.xml里需要添加的：

<filter>
		<filter-name>characterEncoding</filter-name>
		<filter-class>cn.seekool.skserver.filter.SetCharacterEncodingFilter</filter-class>
		<init-param>
			<param-name>encoding</param-name>
			<param-value>utf-8</param-value>
		</init-param>
		<init-param>
			<param-name>ignore</param-name>
			<param-value>true</param-value>
		</init-param>
	</filter>
    <filter-mapping>
		<filter-name>characterEncoding</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>