jdbcutil.java

达内IT培训Java DAO 源码 是学习Java用DAO方式连接数据库编程的好东西

package dao;

import java.io.FileInputStream;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class JdbcUtil {
//	private static String driver="org.apache.derby.jdbc.ClientDriver";
//	private static String url="jdbc:derby://localhost:1527/test";
//	private static String user="app";
//	private static String password="app";
//	private static Connection con;
	
	public static Connection getConnection()throws Exception{
		Properties props=new Properties();
		InputStream in=new FileInputStream("jdbc.properties");
		props.load(in);
		in.close();
		String driver=props.getProperty("driver");
		String url=props.getProperty("url");
		String user=props.getProperty("user");
		String password=props.getProperty("password");
		
		Class.forName(driver);
		return DriverManager.getConnection(url,user,password);
	}
	
	public static void close(ResultSet rs,Statement st,Connection con) {
		if(rs!=null){
			try {
				rs.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(st!=null){
			try {
				st.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		if(con!=null){
			try {
				con.close();
			} catch (SQLException e) {
				e.printStackTrace();
			}
		}
		
	}
	
	public static void main(String[] args) throws Exception{
		Connection con=getConnection();
		System.out.println(con);
	}
}