CharacterEncodingFilter.java
上传用户:junmaots
上传日期:2022-07-09
资源大小:2450k
文件大小:3k
源码类别:
Jsp/Servlet
开发平台:
Java
- package com.mycompany.filter;
- 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;
- public class CharacterEncodingFilter implements Filter {
- /**
- * The default character encoding to set for requests that pass through
- * this filter.
- */
- protected String encoding = null;
- /**
- * The filter configuration object we are associated with. If this value
- * is null, this filter instance is not currently configured.
- */
- protected FilterConfig filterConfig = null;
- /**
- * Should a character encoding specified by the client be ignored?
- */
- protected boolean ignore = true;
- /**
- * Place this filter into service.
- *
- * @param filterConfig The filter configuration object
- */
- 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;
- }
- }
- /**
- * Take this filter out of service.
- */
- public void destroy() {
- this.encoding = null;
- this.filterConfig = null;
- }
- /**
- * Select and set (if specified) the character encoding to be used to
- * interpret request parameters for this request.
- *
- * @param request The servlet request we are processing
- * @param result The servlet response we are creating
- * @param chain The filter chain we are processing
- *
- * @exception IOException if an input/output error occurs
- * @exception ServletException if a servlet error occurs
- */
- public void doFilter(ServletRequest request, ServletResponse response,
- FilterChain chain)
- throws IOException, ServletException {
- // Conditionally select and set the character encoding to be used
- if (ignore || (request.getCharacterEncoding() == null)) {
- String encoding = selectEncoding(request);
- if (encoding != null) {
- request.setCharacterEncoding(encoding);
- }
- }
- // Pass control on to the next filter
- chain.doFilter(request, response);
- }
- /**
- * Select an appropriate character encoding to be used, based on the
- * characteristics of the current request and/or filter initialization
- * parameters. If no character encoding should be set, return
- * <code>null</code>.
- * <p>
- * The default implementation unconditionally returns the value configured
- * by the <strong>encoding</strong> initialization parameter for this
- * filter.
- *
- * @param request The servlet request we are processing
- */
- protected String selectEncoding(ServletRequest request) {
- return this.encoding;
- }
- }