jdbc怎么连接数据库

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;

public class Test{
	public static final String USER = "user";
	public static final String PASS = "password";
	public static final String DRIVER = "oracle.jdbc.OracleDriver";
	public static final String URL = "jdbc:oracle:thin:@166.111.192.153:1521:orcl";
	public static void main(String args[]) throws SQLException{
		new Test().connection();
	}
	public void connection() throws SQLException{
		Connection conn = null ;
		Statement stmt = null ;
		String sql = "SELECT * FROM USERDATA";//查询语句
		try{
			Class.forName(DRIVER) ; //载入驱动
			conn = DriverManager.getConnection(URL,USER,PASS) ; //连接Oracle第一个参数是连接地址,第二,三个账号与密码
			stmt = conn.createStatement();  //创建查询
			ResultSet rs = stmt.executeQuery(sql); //查询
			while(rs.next()){	//查询数据库数据打印输出
				System.out.println(rs.getString(1)); 	//这里的rs.getString(1);的参数1代表查询数据库第一条数据
				System.out.println(rs.getString(2)); 	//查询第二条数据
			}
			}catch(Exception ex){
				ex.printStackTrace();
				}finally{ //关闭连接
					conn.close();
					stmt.close();
				}
	}
}

      如果需要查询自己电脑上数据库需要修改的是连接地址,与账号密码,查询语句.    当然连接之前需先载入jdbc驱动