引用 mysql-connector-jav 的jar
配置文件为 database.propertties
1 package JDBCDemo; 2 3 import java.io.FileInputStream; 4 import java.io.FileNotFoundException; 5 import java.io.IOException; 6 import java.io.InputStream; 7 import java.sql.DriverManager; 8 import java.sql.PreparedStatement; 9 import java.sql.ResultSet; 10 import java.sql.SQLException; 11 import java.util.InputMismatchException; 12 import java.util.Properties; 13 14 import com.mysql.jdbc.Connection; 15 import com.mysql.jdbc.Statement; 16 17 public class JDBCUtils { 18 private void JDBCUtils() {}; 19 private static String sqlurl = ""; 20 private static String sqluser = ""; 21 private static String sqlpwd = ""; 22 private static String classforName = ""; 23 private static Connection con = null; 24 25 static { 26 try { 27 initConfig(); 28 Class.forName(classforName); 29 con = (Connection) DriverManager.getConnection(sqlurl, sqluser, sqlpwd); 30 } catch (ClassNotFoundException e) { 31 System.out.println("数据驱动失败"); 32 e.printStackTrace(); 33 } catch (SQLException e) { 34 35 System.out.println("数据连接失败"); 36 e.printStackTrace(); 37 } 38 } 39 40 private static void initConfig() { 41 InputStream inf = JDBCUtils.class.getClassLoader().getResourceAsStream("database.propertties"); 42 Properties properties = new Properties(); 43 try { 44 properties.load(inf); 45 classforName = properties.getProperty("driverClass"); 46 sqlurl = properties.getProperty("url"); 47 sqluser = properties.getProperty("username"); 48 sqlpwd = properties.getProperty("password"); 49 } catch (IOException e) { 50 System.out.println("读取配置文件失败"); 51 } 52 } 53 54 public static Connection getConnection() { 55 return con; 56 } 57 public static void close(Connection con,Statement preparedStatement,ResultSet rs) { 58 if(con !=null) { 59 try { 60 con.close(); 61 } catch (SQLException e) { 62 //e.printStackTrace(); 63 } 64 65 } 66 if (preparedStatement!=null) { 67 try { 68 preparedStatement.close(); 69 } catch (Exception e) { 70 //e.printStackTrace(); 71 } 72 } 73 if (rs!=null) { 74 try { 75 rs.close(); 76 } catch (Exception e) { 77 //e.printStackTrace(); 78 } 79 } 80 } 81 }