imgservlet.java

java结合ajax编写的简易留言本

package anni.gbook.ajax;

import java.io.IOException;
import java.io.PrintWriter;

import java.util.logging.Logger;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;


/**
 * 显示图片.
 * @author Lingo
 * @version 1.0
 * @since 2006-01-19
 */
public class ImgServlet extends HttpServlet {
    /**
     * 日志.
     */
    private Logger log = Logger.getLogger(ImgServlet.class.getName());

    /**
     * dao接口.
     */
    private String title = Constants.TITLE;

    //String copyright = Constants.copyright;
    //String password = Constants.password;
    /**
     * 所有图片.
     */
    private String[] images = Constants.IMAGES;

    /**
     * 处理get请求.
     * @param request 请求
     * @param response 响应
     * @throws ServletException servlet异常
     * @throws IOException io异常
     */
    protected final void doGet(final HttpServletRequest request,
        final HttpServletResponse response)
        throws ServletException, IOException {
        log.info("start");

        response.setContentType("text/xml");
        response.setCharacterEncoding("GBK");

        StringBuffer buff = new StringBuffer();

        buff.append("<?xml version=\"1.0\" encoding=\"GBK\"?>")
            .append("<constants>").append("<title>").append(title)
            .append("</title>").append(getImages()).append("</constants>");

        PrintWriter out = response.getWriter();
        out.print(buff.toString());

        log.info("end");
    }

    /**
     * 获得所有图片的xml字符串.
     * @return String xml
     */
    private String getImages() {
        StringBuffer buff = new StringBuffer();
        int len = images.length;

        for (int i = 0; i < len; i++) {
            buff.append("<image>").append(images[i]).append("</image>");
        }

        return buff.toString();
    }
}