dboperation.java

java telephone notebook

import java.sql.*;
import javax.swing.JOptionPane;
import javax.sql.rowset.*;

public class DbOperation{
	private ConfigReader configRead;
	private String JDBC_DRIVER;
	private String DB_URL;
	private String USER;
	private String PSD;
	
	private Connection connection;
	private Statement statement;
	private ResultSet resultSet;
	private CachedRowSet rowSet;
	
	public DbOperation(){
		configRead = new ConfigReader("db.conf");
		JDBC_DRIVER = configRead.get("JDBC_DRIVER");
		DB_URL = configRead.get("DB_URL");
		USER = configRead.get("USER");
		PSD = configRead.get("PSD");
		try{
			Class.forName(JDBC_DRIVER);
		}
		catch(Exception e){
			JOptionPane.showMessageDialog(null,"加载数据库驱动器失败！","错误提示",JOptionPane.ERROR_MESSAGE);
		}
	}
	
	public CachedRowSet executeQuery(String sql){
		try{
			rowSet = new com.sun.rowset.CachedRowSetImpl();
			if(connection==null)
				dbConnect();
			resultSet = statement.executeQuery(sql);
			rowSet.populate(resultSet);
		}
		catch(Exception e){
			JOptionPane.showMessageDialog(null,"数据库查询失败！","错误提示",JOptionPane.ERROR_MESSAGE);
		}
		finally{
			dbClose();
		}
		return rowSet;
	}
	
	public void executeUpdate(String sql){
		try{
			if(connection == null)
				dbConnect();
			statement.executeUpdate(sql);
			JOptionPane.showMessageDialog(null,"更新成功！","提示",JOptionPane.INFORMATION_MESSAGE);
		}
		catch(Exception e){
			JOptionPane.showMessageDialog(null,"更新数据库失败！","错误提示",JOptionPane.ERROR_MESSAGE);
		}
		finally{
			dbClose();
		}
	}
	
	public void dbConnect(){
		try{
			connection = DriverManager.getConnection(DB_URL,USER,PSD);
			statement = connection.createStatement();
		}
		catch(Exception e){
			JOptionPane.showMessageDialog(null,"连接数据库失败！","错误提示",JOptionPane.ERROR_MESSAGE);
		}
	}
	
	public void dbClose(){
		try{
			if(connection!=null)
				connection.close();
			connection = null;
		}
		catch(Exception e){
			JOptionPane.showMessageDialog(null,"关闭数据库连接失败！","错误提示",JOptionPane.ERROR_MESSAGE);
		}
		
	}
}