Java 如何为一个特定的servlet应用过滤器？

在我的聊天应用程序中，我有五个servlet。我需要为一个servlet应用过滤器

我的过滤器是

package com.tps.flexchat.action;

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;

/**
 * Servlet Filter implementation class EncodingFilter
 */
public class EncodingFilter implements Filter {
    private String encoding = "UTF-8";
    private FilterConfig filterConfig;
    /**
     * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
     */
    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
    }

    /**
     * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
     */
    public void doFilter(ServletRequest req, ServletResponse resp,FilterChain chain) throws IOException, ServletException {

        resp.setCharacterEncoding("encoding");
        resp.setContentType("encoding");
                    req.setCharacterEncoding(encoding);
        chain.doFilter(req, resp);

        System.out.println("filter -------> :"+encoding );
    }

    /**
     * @see javax.servlet.Filter#destroy()
     */
    public void destroy() {
    }

}

web.xml中的映射将是

<filter>
    <display-name>EncodingFilter</display-name>
    <filter-name>EncodingFilter</filter-name>
    <filter-class>com.tps.flexchat.action.EncodingFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>EncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
</filter-mapping>

---

提前感谢….

您可以更改过滤器路径：

将

更改为与servlet相同的路径

<filter>
    <display-name>EncodingFilter</display-name>
    <filter-name>EncodingFilter</filter-name>
    <filter-class>com.tps.flexchat.action.EncodingFilter</filter-class>
</filter>
<filter-mapping>
    <filter-name>EncodingFilter</filter-name>
    <url-pattern>/SendMessageAction/</url-pattern>
</filter-mapping>

编码滤波器
编码滤波器
com.tps.flexchat.action.EncodingFilter
编码滤波器
/SendMessageAction/

您还可以通过引用servlet名称而不是url模式，将筛选器应用于特定servlet。如果您的servlet是这样声明的：

<servlet>
    <servlet-name>SendMessageAction</servlet-name>
    <servlet-class>com.tps.flexchat.action.SendMessageAction</servlet-class>
</servlet>

SendMessageAction
com.tps.flexchat.action.SendMessageAction

您应该能够使用以下筛选器映射：

<filter-mapping>
    <filter-name>EncodingFilter</filter-name>
    <servlet-name>SendMessageAction</servlet-name>
</filter-mapping>

编码滤波器
SendMessageAction

为什么不将与Servlet相同的路径应用到您的过滤器上？谢谢您的回复…您能给我代码吗？您的Servlet路径将是web.xml，类似这样：Servlet/path/这是正确的兄弟吗/SendMessageAction？/SendMessageAction/？不错，我不知道！我喜欢这种方法，因为它更直接。

<filter-mapping>
    <filter-name>EncodingFilter</filter-name>
    <servlet-name>SendMessageAction</servlet-name>
</filter-mapping>