servlet脏话过滤器简单案例

以下是一个简单的Servlet脏话过滤器的示例：

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

@WebFilter(filterName = "DirtyWordsFilter", urlPatterns = {"/*"})
public class DirtyWordsFilter implements Filter {
    private static final String[] DIRTY_WORDS = {"xxx", "yyy", "zzz"};

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        String requestURI = httpRequest.getRequestURI();

        if (requestURI != null && !requestURI.endsWith(".css") && !requestURI.endsWith(".js")) { // 排除静态资源
            String message = httpRequest.getParameter("message");
            if (message != null) {
                for (String dirtyWord : DIRTY_WORDS) {
                    message = message.replaceAll(dirtyWord, "***");
                }
                request.setAttribute("message", message); // 将过滤后的消息存入request中
            }
        }

        chain.doFilter(request, response);
    }

    @Override
    public void destroy() {
    }
}

该过滤器会拦截所有请求，并排除静态资源。如果请求中包含名为"message"的参数，该过滤器会检查该参数中是否包含脏话，如果包含，则将其替换为"***"，并将过滤后的消息存入request中。开发人员可以在servlet中获取过滤后的消息并进行处理。