Filter 自定义字符编码过滤器 CharacterFilter

一时失言乱红尘 2023-05-30 06:17 1阅读 0赞

## Code ##

XML配置：

<filter>
    	<filter-name>CharacterFilter</filter-name>
    	<filter-class>a.b.filter.CharacterFilter</filter-class>
    	<init-param>
    		<param-name>encoding</param-name>
    		<param-value>UTF-8</param-value>
    	</init-param>
    	<init-param>
    		<param-name>contentType</param-name>
    		<param-value>text/html;charset=UTF-8</param-value>
    	</init-param>
    </filter>
    <filter-mapping>
    	<filter-name>CharacterFilter</filter-name>
    	<url-pattern>/*</url-pattern>
    </filter-mapping>

使用Servlet 3.0的新注解，替代XML配置。

import java.io,IOException;
    import javax.servlet.*;
    import javax.servlet.http.*;
    import javax.servlet.annotation.*;
    
    @WebFilter(
    	urlPatterns = "/*",
    	initParams = {
    		@WebInitParam(name = "encoding", value = "UTF-8"),
    		@WebInitParam(name = "contentType", value = "text/html;charset=UTF-8")
    	}
    )
    public class CharsetFilter implements Filter {
    	
    	private String encoding;
    	private String contentType;
    
    	public void init(FilterConfig filterConfig) throws ServletException {
    		this.encoding = filterConfig.getInitParameter("encoding");
    		this.contentType = filterConfig.getInitParameter("contentType");
    	}
    	
    	public void destroy() {
    	}
    
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    		HttpServletRequest req = (HttpServletRequest) request;
    		HttpServletResponse resp - (HttpServletResponse) response;
    		
    		req.setCharacterEncoding(encoding);
    		resp.setCharacterEncoding(encoding);
    		resp.setContentType(contentType);
    		
    		chain.doFilter(req, resp);
    	}
    	
    }