在web.xml 裡面設定

<filter>
<filter-name>Set Character Encoding</filter-name>
<filter-class>filter.SetEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>Set Character Encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
 

然後建立一個設定編碼格式的類叫做：SetEncodingFilter

package filter;

import javax.servlet.*;
import java.io.IOException;

/**
 * Created by  on 2017/3/23.
 */
public class SetEncodingFilter implements Filter {
    protected String encoding = null;//定義預設字元編碼方式
    protected boolean ignore = true;//定義客戶端指定的編碼方式是否應被忽略
    protected FilterConfig filterConfig = null;//定義過濾器配置物件,若為null,則說明過濾器未配置

    public void destroy()//停止過濾器的工作
    {
        this.encoding = null;
        this.filterConfig = null;
    }

    //設定字元編碼
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
            throws IOException, ServletException {
        if (ignore || (req.getCharacterEncoding() == null)) {
            req.setCharacterEncoding(encoding);
        }
        chain.doFilter(req, res);
    }

    //啟動過濾器
    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 this.ignore = value.equalsIgnoreCase("true")
                || value.equalsIgnoreCase("yes");
    }

}