java覆盖方法初始化

当实现或继承一个方法并且覆盖它本身的方法时,如果覆盖的是init()方法,记得初始化,否则会出现空指针异常!!!
例子:

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public abstract class MyGenericServlet implements Servlet, ServletConfig {
private ServletConfig servletConfig;
@Override
public void init(ServletConfig servletConfig) throws ServletException {
// TODO Auto-generated method stub
this.servletConfig = servletConfig;
}
......
}
- - -
public class LoginServlet extends MyGenericServlet {
public void init() throws ServletException {
System.out.println("初始化");
init(); // 记得初始化
}
}