jdbc ----利用配置文件进行数据库连接

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;

public class DBConnection {
private static String CONFIG_FILENAME = "config.properties";
private Properties prop = null;
private String driverName = null;
private String url = null;
private String user = null;
private String password = null;

public DBConnection() throws Exception {
prop = new Properties();
InputStream in = DBConnection.class.getResourceAsStream("/"
+ CONFIG_FILENAME);
prop.load(in);
driverName = prop.getProperty("DataBaseDrivers").trim();
user = prop.getProperty("DataBaseUser");
password = prop.getProperty("DataBaseUserPassword");
url = getDBURL();
Class.forName(driverName).newInstance();

}

private String getDBURL() {
if (prop.getProperty("DataBaseType").equals("MySQL")) {
return "jdbc:mysql://" + prop.getProperty("DataBaseServerName")
+ ":" + prop.getProperty("DataBaseServerPort") + "/"
+ prop.getProperty("DataBaseName");
}
return url;
}

public Connection getConnection() throws SQLException {
return DriverManager.getConnection(url, user, password);

}

public void closeConnection(Connection conn) {
try {
if (conn != null) {
conn.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
}