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JinTianYi456
V2EX    Java

The newInstance() call is a work around for some broken Java implementations

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  •   JinTianYi456 Mar 15, 2021 1529 views
    This topic created in 1871 days ago, the information mentioned may be changed or developed.
    // Notice, do not import com.mysql.jdbc.* // or you will have problems! public class LoadDriver { public static void main(String[] args) { try { // The newInstance() call is a work around for some // broken Java implementations Class.forName("com.mysql.jdbc.Driver").newInstance(); 
    • 问 1: 注释 1,import 会有什么问题?
    • 问 2: 注释 2,这句话怎么理解?
    1 replies    2021-03-15 17:16:38 +08:00
    Brentwans
        1
    Brentwans  
       Mar 15, 2021
    可以从类的加载方向深入看一下。没有深入去看,抛砖引玉了,仅凭记忆如果没记错 jdbc 驱动在构造时候进行了不少的初始化工作。
    第一个避免错误的引入,导致无关对象初始化异常。第二个应该是确保 class 被构造,相应驱动被初始化,从字面理解应该和不同 java 实现有关系。
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