Java 敏感词过滤

public class RequestFilter implements Filter {
/* (non-Javadoc)
* @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
*/
@Override
public void doFilter(ServletRequest arg0, ServletResponse arg1,FilterChain arg2) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) arg0;
HttpServletResponse response = (HttpServletResponse) arg1;
//敏感词汇过滤
GetHttpServletRequestWrapper req = new GetHttpServletRequestWrapper((HttpServletRequest)arg0,"utf-8",request.getRequestURI());
arg2.doFilter(req, response);
}
}

public class GetHttpServletRequestWrapper extends HttpServletRequestWrapper {
	private String charset = "UTF-8";

	private String url;

	public GetHttpServletRequestWrapper(HttpServletRequest request) {
		super(request);
	}

	/**
	 * 获得被装饰对象的引用和采用的字符编码
	 * 
	 * @param request
	 * @param charset
	 */
	public GetHttpServletRequestWrapper(HttpServletRequest request,String charset, String url) {
		super(request);
		this.charset = charset;
		this.url = url;
	}

	/**
	 * 重写getParameter方法获得参数，对特殊字符进行过滤
	 */
	public String getParameter(String name) {
		String value = super.getParameter(name);
		value = value == null ? null : convert(value);
		return value;
	}

	/**
	 * 重写getParameterValues方法获得参数，对特殊字符进行过滤
	 */
	public String[] getParameterValues(String name){
		String[] values = super.getParameterValues(name);
		if(values!=null && values.length>0){
			values[0] = values[0] == null ? null : convert(values[0]);
		}
		return values;
	}

	/**
	 * 过滤规则
	 * @param target
	 * @return
	 */
	public String convert(String target) {
		//target =  StringEscapeUtils.escapeHtml(target);
		//target =  StringEscapeUtils.escapeJavaScript(target);
		//敏感词汇信息
		List<SensitiveWord> swList = SwConstant.ALL_SW_LIST;
		//判断是否拦截，把拦截的内容替换为相应的*
		if(null != url && (url.contains("/discuss/add") || url.contains("/discuss/addLivelDiscuss") || url.contains("/suggestion/add"))){
			if(null != swList && !swList.isEmpty()){
				int num = 0;
				for(SensitiveWord sw : swList){
					if(null != sw.getSw() && !"".equals(sw.getSw()) && target.contains(sw.getSw().trim())){
						StringBuffer repStr = new StringBuffer();
						num = sw.getSw().trim().length();
						for(int i=0;i<num;i++){
							repStr.append("*");
						}
						target = target.replace(sw.getSw(), repStr);
					}
				}
			}
		}
		return target;
	}
}

web.xml中配置

<filter>
    <filter-name>RequestFilter</filter-name>
    <filter-class>gt.common.RequestFilter</filter-class>
    <async-supported>true</async-supported>
  </filter>
  <filter-mapping>
    <filter-name>RequestFilter</filter-name>
    <url-pattern>*.action</url-pattern>
  </filter-mapping>
  <filter-mapping>
    <filter-name>RequestFilter</filter-name>
    <url-pattern>*.jsp</url-pattern>
  </filter-mapping>