JDBC连接数据库

package org.lans.test;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

public class JDBCConnect {
    private static String url;
    private static String username;
    private static String password;
    public static void getProps(){
        Properties props=new Properties();
        try {
            props.load(JDBCConnect.class.getClassLoader().getResourceAsStream("jdbc.properties"));
            /**
             * mysql驱动类:com.mysql.jdbc.Driver
             * mysql url:jdbc:mysql://localhost:3306/database
             * oracle驱动类:oracle.jdbc.driver.OracleDriver
             * oracle url:jdbc:oracle:thin:@localhost:1521:database
             * DB2驱动类:com.ibm.db2.jdbc.app.DB2Driver
             * db2 url:jdbc:db2://localhost:5000/sample
             * sql server:net.sourceforge.jtds.jdbc.Driver
             * sql server url:jdbc:jtds:sqlserver://localhost:port/database
             */
            url=props.getProperty("connection.url");
            username=props.getProperty("connection.username");
            password=props.getProperty("connection.password");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    /**
     * 获取数据库连接
     * @return conn
     */
    public static Connection getConnection(){
        getProps();
        Connection conn=null;
        try {
            conn=DriverManager.getConnection(url,username,password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return conn;
    }
    
    public static void close(Connection conn){
        if(conn!=null){
            try {
                conn.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    public static void close(Statement stmt){
        if(stmt!=null){
            try {
                stmt.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
    public static void close(ResultSet rs){
        if(rs!=null){
            try {
                rs.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
    }
}