1 import java.io.FileInputStream; 2 import java.io.IOException; 3 import java.io.InputStream; 4 import java.sql.Connection; 5 import java.sql.DriverManager; 6 import java.sql.ResultSet; 7 import java.sql.SQLException; 8 import java.sql.Statement; 9 import java.util.Properties; 10
11 public class JdbcDemo { 12 //創建對象關聯配置文件
13 private Properties pro = new Properties(); 14 private String driver; 15 private String url; 16 private String user; 17 private String psw; 18
19 public JdbcDemo(){ 20 try { 21 //通過反射獲取數據流
22 pro.load(this.getClass().getResourceAsStream("MyOrcDb.properties")); 23 //獲取配置文件數據
24 this.setDriver(pro.getProperty("driver")); 25 this.setUrl(pro.getProperty("url")); 26 this.setUser(pro.getProperty("user")); 27 this.setPsw(pro.getProperty("psw")); 28 } catch (IOException e) { 29 e.printStackTrace(); 30 } 31 } 32
33 private void minSalName(){ 34
35 //連接數據庫
36 try { 37 Class.forName(driver); 38 //獲取連接
39 Connection con; 40 con = DriverManager.getConnection(url,user,psw); 41 //sql語句載入數據庫
42 Statement st = con.createStatement(); 43 //讀取各部門最低工資名單 44 //關閉數據庫
45 String sql = "SELECT emp.deptno,emp.ename,emp.sal from emp,"
46 + "(SELECT deptno,min(sal) minSal from emp GROUP BY deptno) a "
47 + "where emp.deptno = a.deptno "
48 + "and emp.sal = a.minsal"; 49 //獲得結果集
50 ResultSet rst = st.executeQuery(sql ); 51 //獲得結果集的列數
52 int n = rst.getMetaData().getColumnCount(); 53 //遍歷結果集
54 String str = ""; 55 for(;rst.next();){ 56 for(int i=1;i<=n;i++){ 57 str += rst.getString(i)+"\t"; 58 } 59 str += "\n"; 60 } 61 System.out.println(str); 62 //關閉JDBC(先開后關)
63 rst.close(); 64 st.close(); 65 con.close(); 66 } catch (ClassNotFoundException e) { 67 e.printStackTrace(); 68 } 69 catch (SQLException e) { 70 e.printStackTrace(); 71 } 72 } 73 public String getDriver() { 74 return driver; 75 } 76 public void setDriver(String driver) { 77 this.driver = driver; 78 } 79 public String getUrl() { 80 return url; 81 } 82 public void setUrl(String url) { 83 this.url = url; 84 } 85 public String getUser() { 86 return user; 87 } 88 public void setUser(String user) { 89 this.user = user; 90 } 91 public String getPsw() { 92 return psw; 93 } 94 public void setPsw(String psw) { 95 this.psw = psw; 96 } 97 public static void main(String[] args) { 98 JdbcDemo jdbc = new JdbcDemo(); 99 jdbc.minSalName(); 100 } 101
102 }