本人分别用过 asp, asp.net 和 java 开发web应用程序,但发现java别的地方都好,就是乱码问题实在让人头大:1、在一台机器上运行得好好的程序,拷贝工程到另一台机器上运行时就变成了乱码
2、本来一个好好的html或jsp页面,如果是从一个 servlet 中 forward 过来,就变成了乱码
3、硬编码的一条插入语句,存到数据库中去却变成了乱码
......不同的问题要用不同的办法解决
实在想不明白 tomcat 中为什么会有那么多种编码,很多配置文件是用 UTF-8,但有些配置文件却用 ISO-8859-1。Unicode 被应用已经不止10年了,为什么象 ISO-8859-1 这类编码还在tomcat中被一直使用,害得中国的java程序员一直被编码问题蹂躏。人家 asp.net 的乱码问题就很少,有时出现一点,差不多在一个配置文件设置一次就可以全部搞掂,为什么 tomcat 不可以呢。
2、本来一个好好的html或jsp页面,如果是从一个 servlet 中 forward 过来,就变成了乱码
3、硬编码的一条插入语句,存到数据库中去却变成了乱码
......不同的问题要用不同的办法解决
实在想不明白 tomcat 中为什么会有那么多种编码,很多配置文件是用 UTF-8,但有些配置文件却用 ISO-8859-1。Unicode 被应用已经不止10年了,为什么象 ISO-8859-1 这类编码还在tomcat中被一直使用,害得中国的java程序员一直被编码问题蹂躏。人家 asp.net 的乱码问题就很少,有时出现一点,差不多在一个配置文件设置一次就可以全部搞掂,为什么 tomcat 不可以呢。
2:<a href="aaa?userName='张三'"> 这种形式传的需要在接收的servlet里做如下操作
String userName=request.getParameter("userName");
byte[] temp=userName.getBytes("ISO-8859-1");
userName=new String(temp,"GBK");
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;/**
* @author Administrator
*
* 更改所生成类型注释的模板为
* 窗口 > 首选项 > Java > 代码生成 > 代码和注释
*/
public class SetCharacterEncodingFilter 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;
// --------------------------------------------------------- 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 <strong>encoding</strong> initialization parameter for this
* filter.
*
* @param request The servlet request we are processing
*/
protected String selectEncoding(ServletRequest request) { return (this.encoding); }}
在web.xml文档中加上:
<filter>
<filter-name>Set Character Encoding</filter-name>
<filter-class>com.lanzhengwu.SetCharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>GBK</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Set Character Encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<%@ page contentType="text/html;charset=UTF-8"%> JDBC连接数据库时
String url="jdbc:mysql://hostname/database?useUnicode=true&characterEncoding=utf8"; 数据库的字符集也是uft8 以上三个条件都满足了,那么任何字符(即使是阿拉伯文)都不会出乱码了!
如果只是中文可以考虑都设成GBK.