smisdb.java

来自「用java2核心类库写的一个学生课程管理系统」· Java 代码 · 共 256 行

import java.sql.*;
import java.util.*;
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;

public class SMISDB
{
	private Connection conn;
	private Statement stat;
	private ResultSet res;
	private ResultSetMetaData rsmeta;
	private JTable table;
	private String querystr;
	private Container container;
	
	private Vector columnheads = new Vector();
	private	Vector rows = new Vector();
	
	public SMISDB()
    {
		try 
		{
			Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");//加载驱动程序
		}
		catch (ClassNotFoundException ex)
		{
			//in fact, not find exception here.
		}
		try 
		{
			//conn = DriverManager.getConnection (url, userName, password);
			conn = DriverManager.getConnection ("jdbc:odbc:SMIS_SOURCE","","");//建立连接，SMIS_SOURCE为数据源
			stat = conn.createStatement();//创建Statement对象
		}
		catch (SQLException ex)
		{
			//sql exception
			System.out.println("sql exception: connect or driver!!!!");
		}
	}
	
	public int getTable(String str,Container cont, boolean isShowTable) 
	{
		container = cont;
	
		try 
		{
			this.querystr = str;
			if (querystr.startsWith("select") || querystr.startsWith("SELECT"))
			{
				System.out.println("-----------select------------------- ");
				this.res = stat.executeQuery(querystr);
				System.out.println("----------executeQuery ok------------------------------ ");

				if ( this.getResultSet(res) >= 0)
				{
					if (isShowTable)
					{
					    // add table to container, and show table in container
					    table = new JTable(rows,columnheads);
			            JScrollPane scroller = new JScrollPane(table);
			            container.add(scroller,BorderLayout.CENTER);
			            container.validate();

				    	cont.setSize(500,600);
                        cont.setVisible(true);
                        table.setEnabled(false);
                        
					}
					else
					{
						//table.setEnabled(true);
						System.out.println("-----------setEnabled(true)--------------- ");
						
					}
					return 1;
                   // table.setEditingRow(false);
                   // table.setEditingColumn(true);
                   /*if (isShowTable)
					{
						table.setEnabled(true);
						System.out.println("-----------setEnabled(true)--------------- ");
						//updateTable();
					}
					else
					{
						table.setEnabled(false);
					}
					*/

				}
				else
				{
					JOptionPane.showMessageDialog(cont,"没有找到记录！");
					cont.setVisible(false);
					return -1;
				}
			}
			else
			{
				System.out.println("-----------not select------------------- ");
				int updateCount = stat.executeUpdate(querystr);

				if (updateCount >0)
				{
					JOptionPane.showMessageDialog(cont,"sql success: modify one or more record ");
				}
				else
				{
					JOptionPane.showMessageDialog(cont,"没有输入信息，请重输！");
				}
				conn.close();
				return updateCount;
			}

				
			//System.out.println("-------6666666666666--------------------------------- ");

		}
		catch (SQLException ex)
		{
			System.out.println("sql exception: sql statment");
			cont.setVisible(false);
			//JOptionPane.showMessageDialog(cont,"输入有误，请重输!");
			JOptionPane.showMessageDialog(cont,ex.getMessage());
		}
		return 0;
	}
	
	public int getResultSet(ResultSet rs) throws SQLException 
	{
		boolean moreRecord = rs.next();
		if (!moreRecord)
		{
			return -1;
		}
		//Vector columnheads = new Vector();
		//Vector rows = new Vector();
		try 
		{
			ResultSetMetaData rsmd = rs.getMetaData();
			for (int i =1;i<=rsmd.getColumnCount();i++)
				columnheads.addElement(rsmd.getColumnName(i));
			do 
			{
				rows.addElement(getNextRow(rs,rsmd));
			} while (rs.next());
			/*
			table = new JTable(rows,columnheads);
			JScrollPane scroller = new JScrollPane(table);
			container.add(scroller,BorderLayout.CENTER);
			
			container.validate();
			*/
			return 0;
		}
		catch(SQLException ex)
		{
			System.out.println("sql exception: getResultSet function");
			return -2;
		}
	}
	
	public Vector getNextRow(ResultSet rs, ResultSetMetaData rsmd) throws SQLException 
	{
		Vector currentRow = new Vector();
		for (int i =1; i<=rsmd.getColumnCount();i++)
			currentRow.addElement(rs.getString(i));
		return currentRow;
	}
	
	public ResultSet getRow(String strx) throws SQLException 
	{
		this.res = this.stat.executeQuery(strx);
		return this.res;
	}
	
	public Vector getVectorData()
	{
		return this.rows;
	}
		
	
	public int login(String sql, String user, String password)
	{
		System.out.println("SMISDB.login-----begin");
		String usertemp = null;
		String passwordtemp = null;
		querystr = sql;
		
		try
		{
		    res = stat.executeQuery(querystr);
	    	boolean moreRecord = res.next();
		    if (!moreRecord)      // no record 
	    	{
	    		return 0;
	    	}
	    	else
	    	{
		    	do
			    {
			    	usertemp = res.getString("用户名");
			    	passwordtemp = res.getString("密码");
			    	if ((usertemp.equals(user)) && (passwordtemp.equals(password) ))
			    	{
			    		//user and password is correct
			    		return 1;
			    	}
		    	}while(res.next());
		    	return -1;
	    	}
		}
		catch(SQLException ex)
		{
			System.out.println("sql exception: login function");
			ex.getMessage();
			return -2;
		}
	}
	
}

/*
class UpdateFrame extends JFrame
{
	public UpdateFrame(String tableName)
	{
		if (tableName == "学生信息")
		{
			
		}
		else if (tableName == "课程信息")
		{
			
		}
		else if (tableName == "学生成绩")
		{
			
		}
		else if (tableName == "用户信息")
		{
			
		}
		else // tableName error
		{
			System.out.println("tableName error!");
		}
		
	}
}

*/