catemodel.java

java课程的资料以及实验的代码

/*
 *CateModel.java：建立资产类别实体类。
 *包括：与数据库进行增、删、改、查操作。
 */
 
import java.sql.*;
import java.math.*;

public class CateModel {
   String cateid;
   String catename;
   String subcateid;
   String subcatename;
   DbConn dbc;
   Connection conn;
   public CateModel() {
   }
   public CateModel(String n,String e,String p,String r) {
   	cateid = n;
   	catename = e;
   	subcateid = p;
   	subcatename = r;
   }
   
   public void setAll(String p,String r) {
   	catename = p;
   	subcatename = r;
   }
   
   public String getCateId() {
   	return cateid;
   }
   public String getCateName() {
   	return catename;
   }
   public String getSubCateId() {
   	return subcateid;
   }
   public String getSubCateName() {
   	return subcatename;
   }
   public void insert() {
      dbc = new DbConn();
      conn = dbc.getConnection();
      try {
      PreparedStatement pstmt = 
      conn.prepareStatement("insert into CATEGORY (CATEID,CATENAME,SUBCATEID,SUBCATENAME) values (?, ?, ?, ?)");
      pstmt.setInt(1, Integer.parseInt(cateid));          
      pstmt.setString(2, catename);   
      pstmt.setInt(3, Integer.parseInt(subcateid));
      pstmt.setString(4, subcatename);
      pstmt.execute();
      conn.commit();
      conn.close();
      }
      catch (java.sql.SQLException s) {
	System.out.println("exception: " + s.getMessage());
      }
   }
   
   public void select() {
      String sql;
      dbc = new DbConn();
      conn = dbc.getConnection();
      sql = "SELECT CATEID,rtrim(CATENAME),SUBCATEID,rtrim(SUBCATENAME) FROM category where subcateid = "+Integer.parseInt(subcateid);
      try {
      Statement stmt = conn.createStatement();
      ResultSet rset = stmt.executeQuery (sql);
      while (rset.next()) {
      	cateid = rset.getString(1);
        catename = rset.getString(2);
        subcatename = rset.getString(4);
      }
      conn.commit(); 
      rset.close();
      stmt.close();
      conn.close();
      }
      catch (java.sql.SQLException s) {
	System.out.println("exception: " + s.getMessage());
      }
    } 
    
    public void update() {
      dbc = new DbConn();
      conn = dbc.getConnection();
      try {
      PreparedStatement pstmt = 
      conn.prepareStatement("update category set CATENAME = ?,SUBCATENAME = ? where cateid = "+Integer.parseInt(cateid)+" and subcateid = "+Integer.parseInt(subcateid));
      pstmt.setString(1, catename);   
      pstmt.setString(2, subcatename);
      pstmt.execute();
      conn.commit();
      conn.close();
      }
      catch (java.sql.SQLException s) {
	System.out.println("exception: " + s.getMessage());
      }
   }
   
   public void delete() {
      dbc = new DbConn();
      conn = dbc.getConnection();
      try {
      PreparedStatement pstmt = 
      conn.prepareStatement("delete category where cateid = "+Integer.parseInt(cateid)+" and subcateid = "+Integer.parseInt(subcateid));
      pstmt.execute();
      conn.commit();
      cateid = null;
      catename = null;
      subcateid = null;
      subcatename = null;
      conn.close();
      }
      catch (java.sql.SQLException s) {
	System.out.println("exception: " + s.getMessage());
      }
   }
}