oracle的 连接

（一）在src文件夹下定义一个文件定义为database.prperties,里面定义数据的一些基本属性

jdbc.driver_class=oracle.jdbc.driver.OracleDriver  //一般不变
jdbc.connection.url=jdbc:oracle:thin:@localhost:1521:shop //shop是建立的数据库的名称
jdbc.connection.username=market   //market是用户名
jdbc.connection.password=orcl //orcl是登陆密码

(二）定义一个ConfigManager类实现对数据库的连接操作

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

//读取配置文件（属性文件）的工具类
public class ConfigManager {
  private static ConfigManager configManager;
  //读取属性文件
  private static Properties properties;
  private ConfigManager(){
   String configManager="database.properties";
 properties=new Properties();
 InputStream in=ConfigManager.class.getClassLoader().getResourceAsStream(configManager);
 try {
  properties.load(in);
  in.close();
 } catch (IOException e) {
  // TODO Auto-generated catch block
  e.printStackTrace();
 }
  }
 public static ConfigManager getInstance(){
  if(configManager==null)
  {
  configManager=new ConfigManager();
  }
  return configManager;
  }
   public String getString(String key){
   
   return properties.getProperty(key);
   
   }
 
}
 （三)定义一个类来实现连接

protected Connection conn;
 protected Statement stmt;
 protected ResultSet rs;
 protected PreparedStatement ps;
 //建立数据库连接
 public boolean getConnection(){
  //读取配置文件
 String driver=ConfigManager.getInstance().getString("jdbc.driver_class");
 String url=ConfigManager.getInstance().getString("jdbc.connection.url");
 String username=ConfigManager.getInstance().getString("jdbc.connection.username");
 String password=ConfigManager.getInstance().getString("jdbc.connection.password");
 
 
  //注册驱动
  try {
   Class.forName(driver);
   //与数据库建立连接
   try {
    conn=DriverManager.getConnection(url,username,password);
   } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    return false;
   } 
  } catch (ClassNotFoundException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
   return false;
  } 
  return true;
 }