STRUTS乱码问题的解决

STRUTS开发过程中经常会出现乱码问题，尤其是在提交表单的过程中。今天在网上找了好多资料，最后终于把乱码问题解决了。现把解决乱码问题的过程做以记录，以便有同样问题的人和以后参考。

我的开发环境：Tomcat5.5.28,struts1.2,jdk1.5

解决乱码的方法：filter

第一步：建立一个filter的包，在包里建一个自己需要用的filter类，我用的是Tomcat自带的filter类SetCharacterEncodingFilter。

具体代码如下：

/* * $Header: /home/cvs/jakarta-servletapi-5/jsr154/examples/WEB-INF/classes/filters/SetCharacterEncodingFilter.java,v 1.1 2002/09/02 13:14:53 remm Exp $ * $Revision: 1.1 $ * $Date: 2002/09/02 13:14:53 $ * * ==================================================================== * * The Apache Software License, Version 1.1 * * Copyright (c) 1999-2001 The Apache Software Foundation. All rights * reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * * 3. The end-user documentation included with the redistribution, if * any, must include the following acknowlegement: * "This product includes software developed by the * Apache Software Foundation (http://www.apache.org/)." * Alternately, this acknowlegement may appear in the software itself, * if and wherever such third-party acknowlegements normally appear. * * 4. The names "The Jakarta Project", "Tomcat", and "Apache Software * Foundation" must not be used to endorse or promote products derived * from this software without prior written permission. For written * permission, please contact [e-mail]. * * 5. Products derived from this software may not be called "Apache" * nor may "Apache" appear in their names without prior written * permission of the Apache Group. * * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * * [Additional notices, if required by prior licensing conditions] * */ package com.fujitsu.guowei.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; /** * <p>Example filter that sets the character encoding to be used in parsing the * incoming request, either unconditionally or only if the client did not * specify a character encoding. Configuration of this filter is based on * the following initialization parameters:</p> * <ul> * <li><b>encoding</b> - The character encoding to be configured * for this request, either conditionally or unconditionally based on * the <code>ignore</code> initialization parameter. This parameter * is required, so there is no default.</li> * <li><b>ignore</b> - If set to "true", any character encoding * specified by the client is ignored, and the value returned by the * <code>selectEncoding()</code> method is set. If set to "false, * <code>selectEncoding()</code> is called <b>only</b> if the * client has not already specified an encoding. By default, this * parameter is set to "true".</li> * </ul> * * <p>Although this filter can be used unchanged, it is also easy to * subclass it and make the <code>selectEncoding()</code> method more * intelligent about what encoding to choose, based on characteristics of * the incoming request (such as the values of the <code>Accept-Language</code> * and <code>User-Agent</code> headers, or a value stashed in the current * user's session.</p> * * @author Craig McClanahan * @version $Revision: 1.1 $ $Date: 2002/09/02 13:14:53 $ */ public class SetCharacterEncodingFilter implements Filter { // ----------------------------------------------------- Instance Variables /** * 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; // --------------------------------------------------------- Public Methods /** * 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); } /** * 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 if (value.equalsIgnoreCase("yes")) this.ignore = true; else this.ignore = false; } // ------------------------------------------------------ Protected Methods /** * 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 <b>encoding</b> initialization parameter for this * filter. * * @param request The servlet request we are processing */ protected String selectEncoding(ServletRequest request) { return (this.encoding); } }

第二步：修改/WEB-INF/web.xml, 新增以下的filte和filter-mappingr节点：

<filter> 　　<!-- filter名记入 --> <filter-name>SetCharacterEncoding</filter-name> <!-- filter所在包路径记入 --> <filter-class>com.fujitsu.guowei.filter.SetCharacterEncodingFilter</filter-class> 　　<!--encoding方式指定 --> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> </filter> <filter-mapping> <filter-name>SetCharacterEncoding</filter-name> <url-pattern>/*</url-pattern> </filter-mapping>

第三步：启动，乱码问题就解决了！