java - Java 中删除第一次发生的方法

Question

link.removeFirstOccurrence(new Integer(9));

这就是我的教授想要的，但只有当我传递像 link.removeFirstOccurrence(9); 这样的值时它才有效。有什么建议吗？

public boolean removeFirstOccurrence(Object obj) { 
    DNode<E> current = head;
    DNode<E> temp = null;

    if(current != null && current.data == obj) {
        head = current.next;
        return true;

    }
    while(current != null && current.data != obj) {
        temp = current;
        current = current.next;
    }
     if(current == null) {
         return false;
     }

     temp.next = current.next;
     current.next.previous = current.previous;

     return true;
  }

Answer 1

您的代码在 Java 对象比较方面存在问题。要比较值，对于原始数据类型可以使用“==”运算符，但对于非原始数据类型必须使用“equals()”方法

以下是更新的代码:

public boolean removeFirstOccurrence(Object obj) {
    DNode<E> current = head;
    DNode<E> temp = null;

    if (current != null && current.data != null && current.data.equals(obj)) {
        head = current.next;
        return true;

    }
    while (current != null && current.data != null && !current.data.equals(obj)) {
        temp = current;
        current = current.next;
    }
    if (current == null || current.data == null) {
        return false;
    }

    temp.next = current.next;
    current.next.previous = current.previous;

    return true;
}