Berkeley CS 61B Data Structures(in Java) Homework4 加分+讨论帖

另外还想问大家一下，我在把DListNode对象cast成LockDListNode对象后，如果想调用LockDListNode中特有的method或fields为什么一定要用：
((LockDListNode)node).isLocked = true;
来进行操作而不能使用
node = (LockDListNode) node;
node.isLocked = true;

第二种会在编译时显示找不到isLocked这个field

费了老劲啦，看了github的一些代码感觉清楚了很多，不然自己有一些问题总是很难解决

拖了好久，恢复开工

提交hw4作业
谢谢！

交HW4 的作业， 做了很长时间这次

有人知道如何compile吗？为何按照提示
  javac -g list/DListNode.java
我总是compile不成功。。
terminal出错提示如下：
javac: file not found: list/DListNode.java
Usage: javac <options> <source files>
use -help for a list of possible options

先看了下前面大神的归纳 做起来很顺
part3 主要注意的是
1.子类构造出来的本质还是LockDListNode 只是传出来的是临时的DListNode 这样不会打乱父类本身适应
2.子类尽量不要重新定义field 本来挺好 画蛇添足将子类的prev next定义了LockDListNode。 因为平时都是以父类的临时身份用父类的prev next(与子类的不同) 突然转到子类 就gg了。 所以还不如和父类一起共用 prev next

有大神说下 part2 讲了什么吗?

感谢大牛指点。

传不了图片
1.

Now we are testing DList.

Here is a list after insertBack 6, 9, 12: [  6  9  12  ]

Here is the same list after insertBack(15) and insertFront(3): [  3  6  9  12  15  ]

front() should be 3. It is: 3

front's next should be 6. It is: 6

front's next's prev should be 3. It is: 3

After remove the front, the front() should be 6. It is: 6

After insertBefore() and insertAfter(), The first 3 nodes should be 5,6,8. The list is: [  5  6  8  9  12  15  ]

Here is a list after construction: [  ]

isEmpty() should be true. It is: true

length() should be 0. It is: 0

Here is a list after insertFront(3) to an empty list: [  3  ]

Here is a list after insertBack(5) on an empty list: [  5  ]

Here is a list after insertFront 3, 2, 1: [  1  2  3  ]

isEmpty() should be false. It is: false

length() should be 3. It is: 3

Here is the same list after insertBack(4): [  1  2  3  4  ]

Here is a list after insertBack 6, 7: [  6  7  ]

isEmpty() should be false. It is: false

length() should be 2. It is: 2

Here is the same list after insertFront(5): [  5  6  7  ]

2.

Now we are testing LockDList.

Here is a list after insertBack 6, 9, 12: [  6  9  12  ]

Here is the same list after insertBack(15) and insertFront(3): [  3  6  9  12  15  ]

front() should be 3. It is: 3

front's next should be 6. It is: 6

front's next's prev should be 3. It is: 3

We lockNode front()= 3

After remove the locked front, the front() should still be 3. It is: 3

After remove the back, the back() should be 12. It is: 12

After insertBefore(3) and insertAfter(3), The first 3 nodes should be 5,3,8. The list is: [  5  3  8  6  9  12  ]

Here is a list after construction: [  ]

isEmpty() should be true. It is: true

length() should be 0. It is: 0

Here is a list after insertFront(3) to an empty list: [  3  ]

Here is a list after insertBack(5) on an empty list: [  5  ]

Here is a list after insertFront 3, 2, 1: [  1  2  3  ]

isEmpty() should be false. It is: false

length() should be 3. It is: 3

Here is the same list after insertBack(4): [  1  2  3  4  ]

Here is a list after insertBack 6, 7: [  6  7  ]

isEmpty() should be false. It is: false

length() should be 2. It is: 2

Here is the same list after insertFront(5): [  5  6  7  ]