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  • java连接数据库以及连接参数格式

    //链接数据库代码部分  下面具有连接的基本参数可以对照修改(参数存放在file下面的database.properties下面)

    //参数存放在file下面的database.properties下面

    driverClass=com.mysql.jdbc.Driver
    url=jdbc:mysql://localhost:3306/day36
    username=root
    password=root

    //链接数据库代码部分 

    package cn.jy.demo;

    import java.io.IOException;
    import java.io.InputStream;
    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 JDBCUtilsConfig {
    private static Connection con;
    private static String driverClass;
    private static String url;
    private static String username;
    private static String password;
    static {
    try {
    readConfig();
    Class.forName(driverClass);
    con=DriverManager.getConnection(url,username,password);
    } catch (Exception e) {
    throw new RuntimeException("数据库连接失败");
    }


    }
    private static void readConfig() throws IOException{
    InputStream in=JDBCUtilsConfig.class.getClassLoader().getResourceAsStream("database.properties");
    Properties pro = new Properties();
    pro.load(in);
    driverClass=pro.getProperty("driverClass");
    url=pro.getProperty("url");
    username=pro.getProperty("username");
    password=pro.getProperty("password");
    }
    public static Connection getConnection(){
    return con;
    }
    public static void close(Connection con, Statement stat){
    if(stat!=null){
    try {
    stat.close();
    } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }
    if(con!=null){
    try {
    con.close();
    } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }
    }
    }
    }
    public static void close(Connection con, Statement stat,ResultSet rs){
    if(rs!=null){
    try {
    rs.close();
    } catch (SQLException e) {

    e.printStackTrace();
    }
    if(stat!=null){
    try {
    stat.close();
    } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }
    if(con!=null){
    try {
    con.close();
    } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }
    }
    }
    }
    }
    }

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  • 原文地址:https://www.cnblogs.com/Fisherman13/p/10437252.html
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