小编Dav*_*vid的帖子

    /*
  Button

 Turns on and off a light emitting diode(LED) connected to digital  
 pin 13, when pressing a pushbutton attached to pin 2. 


 The circuit:
 * LED attached from pin 13 to ground 
 * pushbutton attached to pin 2 from +5V
 * 10K resistor attached to pin 2 from ground

 * Note: on most Arduinos there is already an LED on the board
 attached to pin 13.


 created 2005
 by DojoDave <http://www.0j0.org>
 modified 30 Aug 2011
 by Tom Igoe

 This …

所以我有我正在研究的这个项目,我需要为它创建自己的ArrayList类.我已经定义了所有方法,但是当我编译时,我的三个方法仍然出现"找不到符号"错误.我有一个如下所示的界面:

public interface FBList {

    public int size();

public void insert(int i, Person person);

public Person remove(int i);

public Person lookUp(int i);

/**
*A class that defines a person
**/
public class Person {
    private String id;
    private long phoneNum;

    public Person(String personID, long phoneNum){
        id = personID;
        phoneNum = phoneNum;
    }
}

如你所见,我有一个内部阶级.我试图在我的另一个实现此接口的文件中使用该类.目前,我的另一个文件中的三个方法给我的问题如下:

/**
    * A method to expand the size of the array if the array is too small
    * @param i  One minus the place in the …

我无法理解两个相同的事物和两个相同的事物之间的概念.令我困惑的是声明"两个对象可以是相同的,这意味着它们是相同的.但是,两个相等的对象并不相同." 请有人帮我理解差异吗？谢谢.