中文编码采用GBK或者gb2312，前者支持的字符集合要大。
具体是：
（1）Jsp页面中设定：<%@ page contentType="text/html; charset=GBK" %>
（2）Servlet中，在response.getWriter()调用之前，执行response.setContentType(”text/html; charset=GBK")
（3）如果在Servlet中没有设定，自行编写toGBK函数，在取得参数时候进行转换，代码如下：
/**
* 做编码的转换，转换成GBK。
* @param str 需要做转换的字符串
* @return String 返回转换后的字符串
*/
public static String toGBK(String str) {
String temp = str;
try {
if (temp == null) {
temp = "";
}
if (temp.equals("null")) {
temp = "";
}
byte[] b = temp.getBytes("ISO8859-1"); //按字节将串拆分
str = new String(b, "GBK"); //按GBK编码方式将字节组合
} catch (UnsupportedEncodingException uee) {
}
return str;
}
（4）编写一个Servlet Filter，在每次响应之前进行编码的转换。这样可以避免在每个Servlet中进行上述的（2）（3）操作。Filter示例如下：
package kellerdu.util;
mport javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import net.sf.hibernate.*;
/**
* <p>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><strong>encoding</strong> - 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><strong>ignore</strong> - 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 <strong>only</strong> 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
* users session.</p>
*/
public class SetEncodingServlet extends HttpServlet 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);
}
}
/**
* 用户认证
*/
try {
HttpServletRequest req = (HttpServletRequest) request;
TblSysUser user = (TblSysUser) req.getSession().getAttribute(
LoginOper.USER);
if (user == null && req.getServletPath().indexOf("login") == -1) {//没有登录
req.getRequestDispatcher("/login.jsp").forward(request,response);
//chain.doFilter(request, response);
} else {
chain.doFilter(request, response);
//每次响应之后关闭Heibernate Session
HibernateUtil.closeSession();
}
} catch (ServletException ex) {
} catch (IOException ex) {
} catch (HibernateException ex) {
}
}
/**
* Place this filter into service.
*
* @param filterConfig The filter configuration object
*/
public void init(FilterConfig filterConfig) throws ServletException {
//System.out.println("SetEncodingServlet inits");
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;
}
try {
com.yingrui.voip.HibernateUtil.closeSession();
} catch (HibernateException ex) {
System.out.println("Hibernate Init Exception！");
}
}
// ------------------------------------------------------ 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);
}
}
相应的web.xml配置如下（这里采用Struts）：
<filter>
<filter-name>setencodingservlet</filter-name>
<filter-class>kellerdu.util.SetEncodingServlet</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>GBK</param-value>
</init-param>
<init-param>
<param-name>ignore</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>setencodingservlet</filter-name>
<url-pattern>*.jsp</url-pattern>
</filter-mapping>
<filter-mapping>
<filter-name>setencodingservlet</filter-name>
<url-pattern>*.do</url-pattern>
</filter-mapping>
