/**
* 1 在方法中固化连接参数
*
* @return 数据库连接
*/
public Connection getConnection() {
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "");
return conn;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 2 通过方法参数方式传递连接参数
*
* @return 数据库连接
*/
public Connection getConnection(String driver, String url, String user, String password) {
Connection conn = null;
try {
Class.forName(driver);
conn = DriverManager.getConnection(url, user, password);
return conn;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
/**
* 3 通过properties配置文件的方式灵活配置连接参数，properties中的属性名固化
*
* @return 数据库连接
*/
public Connection openConnection() {
Connection conn = null;
String driver = "";
String url = "";
String user = "";
String password = "";
Properties props = new Properties();
try {
props.load(this.getClass().getClassLoader()
.getResourceAsStream("db.properties"));
url = props.getProperty("mysql_url");
driver = props.getProperty("mysql_driver");
user = props.getProperty("mysql_user");
password = props.getProperty("mysql_password");
Class.forName(driver);
conn = DriverManager.getConnection(url, user, password);
return conn;
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
