数据库编程

开发平台：
Java

op_book.java：源码内容
							package bookshop.run;
/**
 * <p>管理图书的类，包括图书的修改、查询，删除，添加 </p>
 */
import java.sql.*;
import java.util.Vector;
import bookshop.util.*;
import bookshop.book.*;
import javax.servlet.http.HttpServletRequest;
public class op_book extends DataBase{
  private book abooks = new book();	                       //新的图书类
        private javax.servlet.http.HttpServletRequest request; //建立页面请求
        private boolean sqlflag = true ;		    //对接收到的数据是否正确
        private Vector booklist;			    //显示图书列表向量数组
        private int page = 1;				       //显示的页码
        private int pageSize=10;				//每页显示的图书数
        private int pageCount =0;				//页面总数
        private long recordCount =0;			        //查询的记录总数
        public String sqlStr="";
        public Vector getBooklist() {
                return booklist;
        }
        public boolean getSqlflag() {
                return sqlflag;
        }
        public String to_String( String str) {
                try
                {
                        return new String(str.getBytes("ISO8859-1"));
                }
                catch (Exception e)
                {
                        return str;
                }
        }
        /**
         * 将页面表单传来的资料分解
         */
public boolean getRequest(javax.servlet.http.HttpServletRequest newrequest) {
  boolean flag = false;
  try{
   request = newrequest;
   String ID = request.getParameter("id");
   long bookid = 0;
   try{
           bookid = Long.parseLong(ID);
   }catch (Exception e){
   }
   abooks.setId(bookid);
   String bookname = request.getParameter("bookname");
   if (bookname==null || bookname.equals(""))
   {
           bookname = "";
           sqlflag = false;
   }
   abooks.setBookName(to_String(bookname));
   String author = request.getParameter("author");
   if (author==null || author.equals(""))
   {
           author = "";
           sqlflag = false;
   }
   abooks.setAuthor(to_String(author));
   String publish = request.getParameter("publish");;
   if (publish==null)
   {
           publish = "";
   }
   abooks.setPublish(to_String(publish));
   String bookclass = request.getParameter("bookclass");
   int bc = Integer.parseInt(bookclass);
   abooks.setBookClass(bc);
   String bookno = request.getParameter("bookno");
   if (bookno == null)
   {
           bookno = "";
   }
   abooks.setBookNo(to_String(bookno));
   String picture = request.getParameter("picture");
   if (picture == null)
   {
           picture = "images/01.gif";
   }
   abooks.setPicture(to_String(picture));
   float price;
   try	{
           price =new Float(request.getParameter("price")).floatValue();
   } catch (Exception e){
           price = 0;
           sqlflag = false;
   }
   abooks.setPrince(price);
   int amount;
   try{
           amount = new Integer(request.getParameter("amount")).intValue();
   }catch (Exception e){
           sqlflag = false;
           amount = 0;
   }
   abooks.setAmount(amount);
   String content = request.getParameter("content");
   if (content == null)
   {
           content = "";
   }
   abooks.setContent(to_String(content));
   if (sqlflag)
   {
           flag = true;
   }
   return flag;
                }catch (Exception e){
   return flag;
                }
        }
        /**
         * 获得查询图书类别的sql语句
         * @return
         */
public String getSql() {
   sqlStr = "select id,classname from book order by id";
   return sqlStr;
        }
        /**
         * 完成图书查询，包括分类，分页查询
         * @param res
         * @return
         * @throws java.lang.Exception
         */
public boolean book_search(HttpServletRequest res) throws Exception {
   DataBase db = new DataBase();
   db.connect();
   stmt = db.conn.createStatement ();
   request = res;
   String PAGE = request.getParameter("page");   //页码
   String classid = request.getParameter("classid");	//分类ID号
   String keyword = request.getParameter("keyword");	//查询关键词
   if (classid==null) classid="";
   if (keyword==null) keyword = "";
   keyword = to_String(keyword).toUpperCase();
   try {
           page = Integer.parseInt(PAGE);
   }catch (NumberFormatException e){
           page = 1;
   }
   //取出记录数
   if (!classid.equals("") && keyword.equals("") ) {
           sqlStr = "select count(*) from book where bookclass='"+classid + "'";
      }
  else if (!keyword.equals("")) {
      if (classid.equals("")){
           sqlStr = "select count(*) from book where upper(bookname) like '%" +
                    keyword+ "%' or upper(content) like '%" + keyword + "%'";
      } else {
          sqlStr = "select count(*) from book where bookclass='" + classid
                   + "' and  (upper(bookname) like '%" +keyword+ "%' or "+
                   "upper(content) like '%" + keyword + "%')";
           }
   } else {
           sqlStr = "select count(*) from book";
          }
   int rscount = pageSize;
   try {
           ResultSet rs1 = stmt.executeQuery(sqlStr);
           if (rs1.next()) recordCount = rs1.getInt(1);
           rs1.close();
   }catch (SQLException e){
           System.out.println(e.getMessage());
           return false;
   }
   //设定有多少pageCount
   if (recordCount < 1)
            pageCount = 0;
   else
            pageCount = (int)(recordCount - 1) / pageSize + 1;
   //检查查看的页面数是否在范围内
   if (page < 1)
            page = 1;
  else if (page > pageCount)
            page = pageCount;
            rscount = (int) recordCount % pageSize;	 // 最后一页记录数
   //sql为倒序取值
   sqlStr = "select   a.id,a.bookname,a.bookclass,b.classname,"+
           "a.author,a.publish,a.bookno,a.content,a.prince,a.amount,"+
           "a.Leav_number,a.regtime,a.picture from book a,bookclass b"+
          " where a.Bookclass = b.Id ";
  if (!classid.equals("") && keyword.equals("") ){  //如果类别不为空，非查询
           if (page == 1)
           {
               sqlStr = sqlStr + " and a.bookclass='" + classid + "' "+
               "order by a.Id desc";
           } else {
               sqlStr = sqlStr + " and a.bookclass='" + classid + "limit "+
                       (recordCount-pageSize * page)+","+(recordCount-pageSize * (page-1));
           }
  } else if (!keyword.equals("")) {  //如果是查询资料
    if (page == 1){
      if (!classid.equals("")) {//查询某一类
         sqlStr = sqlStr + "and a.Bookclass='" +
         classid + "' and (upper(a.bookname) like '%" +
         keyword+ "%' or upper(a.content) like '%" +
         keyword + "%')  order by a.Id desc";
      } else {		//查询所有类
        sqlStr = sqlStr + " and (upper(a.bookname) like '%" +
        keyword+ "%' or upper(a.content) like '%" +
        keyword + "%') order by a.Id desc";
      }
     } else {
      if (!classid.equals("")){
           sqlStr = sqlStr + " and a.Bookclass='" +
           classid + "' and (upper(a.bookname) like '%" +
           keyword+ "%' or upper(a.content) like '%" +
           keyword + "%') limit "+(recordCount-pageSize * page)+","+
           (recordCount-pageSize * (page-1));
      } else {
            sqlStr = sqlStr + " and (upper(a.bookname) like '%" +
            keyword+ "%' or upper(a.content) like '%" +
            keyword + "%') limit "+(recordCount-pageSize * page)+","+
            (recordCount-pageSize * (page-1));
            }
                        }
  } else {//非查询，也非分类浏览
         if (page == 1){
              sqlStr = sqlStr + "  order by a.Id desc limit 0,"+pageSize;
          } else {
              sqlStr = sqlStr + "limit "+(recordCount-pageSize * page)+","+
              (recordCount-pageSize * (page-1));
           }
        }
        try  {
              rs = stmt.executeQuery(sqlStr);
              booklist = new Vector(rscount);
              while (rs.next()){
                                book book = new book();
                                book.setId(rs.getLong("id"));
                                book.setBookName(rs.getString("bookname"));
                                book.setBookClass(rs.getInt("bookclass"));
                                book.setClassname(rs.getString("classname"));
                                book.setAuthor(rs.getString("author"));
                                book.setPublish(rs.getString("publish"));
                                book.setBookNo(rs.getString("Bookno"));
                                book.setContent(rs.getString("content"));
                                book.setPrince(rs.getFloat("prince"));
                                book.setAmount(rs.getInt("amount"));
                                book.setLeav_number(rs.getInt("leav_number"));
                                book.setRegTime(rs.getString("regtime"));
                                book.setPicture(rs.getString("picture"));
                                booklist.addElement(book);
                        }
                        rs.close();
                        return true;
                }catch (Exception e){
                        System.out.println(e.getMessage());
                        return false;
                }
        }
        /**
         * 完成图书添加
         * @return
         * @throws java.lang.Exception
         */
 public boolean insert() throws Exception {
  sqlStr = "insert into book (Bookname,Bookclass,Author,Publish,Bookno,"+
           "Content,Prince,Amount,Leav_number,Regtime,picture) values ('";
           sqlStr = sqlStr + dataFormat.toSql(abooks.getBookName()) + "','";
           sqlStr = sqlStr + abooks.getBookClass() + "','";
           sqlStr = sqlStr + dataFormat.toSql(abooks.getAuthor()) + "','";
           sqlStr = sqlStr + dataFormat.toSql(abooks.getPublish()) + "','";
           sqlStr = sqlStr + dataFormat.toSql(abooks.getBookNo()) + "','";
           sqlStr = sqlStr + dataFormat.toSql(abooks.getContent()) + "','";
           sqlStr = sqlStr + abooks.getPrince() + "','";
           sqlStr = sqlStr + abooks.getAmount() + "','";
           sqlStr = sqlStr + abooks.getAmount() + "',";
           sqlStr = sqlStr + "now()"+ ",'";
           sqlStr = sqlStr + abooks.getPicture()+"')";
                try{
                        System.out.print(sqlStr);
                        DataBase db = new DataBase();
                        db.connect();
                        stmt =db.conn.createStatement ();
                        stmt.execute(sqlStr);
                        return true;
                }catch (SQLException sqle){
                  System.out.print(sqle.getMessage());
                        return false;
                }
        }
        /**
         * 完成图书修改
         * @return
         * @throws java.lang.Exception
         */
public boolean update() throws Exception {
  sqlStr = "update book set ";
  sqlStr = sqlStr + "bookname = '" + dataFormat.toSql(abooks.getBookName()) + "',";
  sqlStr = sqlStr + "bookclass = '" + abooks.getBookClass() + "',";
  sqlStr = sqlStr + "Author = '" + dataFormat.toSql(abooks.getAuthor()) + "',";
  sqlStr = sqlStr + "publish = '" + dataFormat.toSql(abooks.getPublish()) + "',";
  sqlStr = sqlStr + "bookno = '" + dataFormat.toSql(abooks.getBookNo()) + "',";
  sqlStr = sqlStr + "content = '" + dataFormat.toSql(abooks.getContent()) + "',";
  sqlStr = sqlStr + "prince = '" + abooks.getPrince() + "',";
  sqlStr = sqlStr + "Amount = '" + abooks.getAmount() + "',";
  sqlStr = sqlStr + "leav_number = '" + abooks.getLeav_number()+ "' ,";
  sqlStr = sqlStr + "picture = '" + abooks.getPicture() + "' ";
  sqlStr = sqlStr + "where id = " + abooks.getId();
                try{
                        DataBase db = new DataBase();
                        db.connect();
                        stmt =db.conn.createStatement ();
                        stmt.execute(sqlStr);
                        return true;
                } catch (SQLException e){
                        System.out.print(e.getMessage());
                        return false;
                }
        }
        /**
         * 完成图书删除
         * @param aid
         * @return
         * @throws java.lang.Exception
         */
        public boolean delete( int aid ) throws Exception {
                sqlStr = "delete from book where id = "  + aid ;
                try
                {         DataBase db = new DataBase();
                          db.connect();
                          stmt =db.conn.createStatement ();
                          stmt.execute(sqlStr);
                         return true;
                }
                catch (SQLException e)
                {
                        System.out.println(e);
                        return false;
                }
              }
              /**
               * 完成图书单本查询，用于支持页面的查看图书详细资料
               * @param newid
               * @return
               * @throws java.lang.Exception
               */
 public boolean getOnebook(int newid ) throws Exception {
     DataBase db = new DataBase();
     db.connect();
     stmt =db.conn.createStatement ();
     try {
        sqlStr="select  a.id,a.bookname,a.bookclass,b.classname,a.author,"+
        "a.publish,a.bookno,a.content,a.prince,a.amount,a.Leav_number,"+
        "a.regtime,a.picture from book a,bookclass b where a.Bookclass="+
        "b.Id and a.Id = " + newid ;
                        rs = stmt.executeQuery(sqlStr);
                        if (rs.next())
                        {	booklist = new Vector(1);
                                book book = new book();
                                book.setId(rs.getLong("id"));
                                book.setBookName(rs.getString("bookname"));
                                book.setBookClass(rs.getInt("bookclass"));
                                book.setClassname(rs.getString("classname"));
                                book.setAuthor(rs.getString("author"));
                                book.setPublish(rs.getString("publish"));
                                book.setBookNo(rs.getString("Bookno"));
                                book.setContent(rs.getString("content"));
                                book.setPrince(rs.getFloat("prince"));
                                book.setAmount(rs.getInt("amount"));
                                book.setLeav_number(rs.getInt("leav_number"));
                                book.setRegTime(rs.getString("regtime"));
                                book.setPicture(rs.getString("picture"));
                                booklist.addElement(book);
                        } else {
                                rs.close();
                                return false;
                        }
                        rs.close();
                        return true;
                }
                catch (SQLException e)
                {
                        return false;
                }
        }
        public int getPage() {				//显示的页码
                return page;
        }
        public void setPage(int newpage) {
                page = newpage;
        }
        public int getPageSize(){			//每页显示的图书数
                return pageSize;
        }
        public void setPageSize(int newpsize) {
                pageSize = newpsize;
        }
        public int getPageCount() {				//页面总数
                return pageCount;
        }
        public void setPageCount(int newpcount) {
                pageCount = newpcount;
        }
        public long getRecordCount() {
                return recordCount;
        }
        public void setRecordCount(long newrcount) {
                recordCount= newrcount;
        }
  public op_book() {
       }
}

						