【Java每日一题】20161229

package Dec2016;  
  
import java.util.ArrayList;  
import java.util.List;  
  
public class Ques1229 {  
  
   public static void main(String[] args){  
       Student stu01 = new Student("001");  
       Student stu02 = new Student(null);  
  
       List<Student> students = new ArrayList<Student>();  
       students.add(stu01);  
       students.add(stu02);  
       System.out.println("students是否包含001学号:"+students.contains(stu01));  
       System.out.println("students是否包含null:"+students.contains(stu02));  
   }  
}  
  
class Student{  
    private String stuId;  
    public Student(String stuId) {  
       super();  
       this.stuId = stuId;  
    }  
    public String getStuId() {  
        return stuId;  
    }  
    public void setStuId(String stuId) {  
        this.stuId = stuId;  
    }  
  
    @Override  
    public boolean equals(Object obj) {  
        if(obj instanceof Student){  
            Student stu = (Student) obj;  
            return stuId.equalsIgnoreCase(stu.getStuId().trim());  
        }  
        return false;  
    }   
}  
今日问题: 
请问主程序输出结果是什么?(点击以下“【Java每日一题】20161229”查看20161228问题解析) 

题目原发布于公众号、简书:【Java每日一题】20161229【Java每日一题】20161229 

 
原文地址:https://www.cnblogs.com/weknow619/p/6231564.html