photoaction.java~4~

来自「一个J2EE模式的」· JAVA~4~ 代码 · 共 75 行

package com.hanb.pic.wkhPic;

import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionForm;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.Action;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import java.io.InputStream;
import java.sql.*;

public class PhotoAction extends Action {
    public ActionForward execute(ActionMapping actionMapping,
                                 ActionForm actionForm,
                                 HttpServletRequest servletRequest,
                                 HttpServletResponse servletResponse) throws
      ServletException, IOException {
        PhotoForm photoForm = (PhotoForm) actionForm;

        //准备接受变量
        ServletOutputStream out = servletResponse.getOutputStream();

        byte buf[]=GetPicBuffer(photoForm.getId()); //从数据库中得到图片的数据

        //开始
        if (buf != null) {
      try {
        int len=buf.length;
        out.write(buf, 0, len);
      }
      catch (IOException ioe) {
        //ioe.printStackTrace();
      }
    }

        return null;
    }

    //从数据库中读出指定id号的图片数据
    public byte[] GetPicBuffer(String id){
       byte[] bufferArray=null;
        try{
            //下面连接数据库
                  Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").
                          newInstance();
                  String url =
                          "jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=TestPic";

                  String user = "sa";
                  String password = "";
                  Connection conn = DriverManager.getConnection(url, user, password);
                  Statement stmt = conn.createStatement(ResultSet.TYPE_SCROLL_SENSITIVE,
                                                        ResultSet.CONCUR_UPDATABLE);

                  String sql_query = "select id from test where id= "; //查询指定id值的记录
                  sql_query+=id;

                  ResultSet rs = stmt.executeQuery(sql_query); //得到查询的结果集


                  if (rs.next()) {
                      bufferArray=rs.getBytes("picData"); //得到数据
                  }
              } catch (Exception e) {
                  e.printStackTrace();
                  System.out.println("Operateor DataBase Error!");
                  return null;
              }
              return bufferArray;
    }
}