Override the equals method in the collection to delete new objects

COPY@Override
public boolean equals(Object obj) {
    
    
	//1.是否为同一对象
	if (this==obj) {
    
    
		return true;
	}
	//2.判断是否为空
	if (obj==null) {
    
    
		return false;
	}
	//3.判断是否是Student类型
	if (obj instanceof Student) {
    
    
		Student student=(Student) obj;
		//4.比较属性
		if(this.name.equals(student.getName())&&this.age==student.age) {
    
    
			return true;
		}
	}
	//不满足，返回false
	return false;
}