package com.java.dbtest; 
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 
import java.sql.SQLException; 
public class TestConnection implements DBTest{ 
public void SelectUser(){ 
//設(shè)定數(shù)據(jù)庫驅(qū)動，數(shù)據(jù)庫連接地址、端口、名稱，用戶名，密碼 
String driverName="oracle.jdbc.driver.OracleDriver"; 
String url="jdbc:oracle:thin:@localhost:1521:BJPOWERNODE"; //test為數(shù)據(jù)庫名稱，1521為連接數(shù)據(jù)庫的默認(rèn)端口 
String user="system"; //aa為用戶名 
String password="bjpowernode"; //123為密碼 
PreparedStatement pstmt = null; 
ResultSet rs = null; 
//數(shù)據(jù)庫連接對象 
Connection conn = null; 
try { 
//反射Oracle數(shù)據(jù)庫驅(qū)動程序類 
Class.forName(driverName); 
//獲取數(shù)據(jù)庫連接 
conn = DriverManager.getConnection(url, user, password); 
//輸出數(shù)據(jù)庫連接 
System.out.println(conn); 
//定制sql命令 
String sql = "select * from t_user where user_id = ?"; 
//創(chuàng)建該連接下的PreparedStatement對象 
pstmt = conn.prepareStatement(sql); 
//傳遞第一個參數(shù)值 root，代替第一個問號 
pstmt.setString(1, "root"); 
//執(zhí)行查詢語句，將數(shù)據(jù)保存到ResultSet對象中 
rs = pstmt.executeQuery(); 
//將指針移到下一行，判斷rs中是否有數(shù)據(jù) 
if(rs.next()){ 
//輸出查詢結(jié)果 
System.out.println("查詢到名為【" + rs.getString("user_id") + "】的信息，其密碼為：" + rs.getString("password")); 
}else{ 
//輸出查詢結(jié)果 
System.out.println("未查詢到用戶名為【" + rs.getString("user_id") + "】的信息"); 
} 
} catch (ClassNotFoundException e) { 
e.printStackTrace(); 
} catch (SQLException e) { 
e.printStackTrace(); 
}finally{ 
try{ 
if(rs != null){ 
rs.close(); 
} 
if(pstmt != null){ 
pstmt.close(); 
} 
if(conn != null){ 
conn.close(); 
} 
} catch (SQLException e) { 
e.printStackTrace(); 
} 
} 
} 
public static void main(String[] args){ 
new TestConnection().SelectUser(); 
} 
}