The implementation of the chain-stack storage structure of Java stack

First, the chain stack

Using a single-linked list to hold all the elements in the stack, this chain-structured stack is called a chain stack.

Second, the stack of the chain storage structure implementation

1  PackageCom.ietree.basic.datastructure.stack;2 3 /**4 * Chain Stack5  *6 * Created by Ietree7 * 2017/4/298  */9  Public classLinkstack<t> {Ten  One     //defines an internal class Node,node instance that represents the node of the chain stack A     Private classNode { -  -         //saving data for a node the         PrivateT data; -         //reference to the next node -         PrivateNode Next; -         //no parameter constructor +          PublicNode () { -         } +         //constructors that initialize all properties A          Publicnode (T data, node next) { at  -              This. data =data; -              This. Next =Next; -  -         } -  in     } -     //Save the stack top element of the chain to     PrivateNode top; +     //Save the number of nodes that are already contained in the link stack -     Private intsize; the     //Create an empty chain stack *      PublicLinkstack () { $         //empty chain stack, top value is nullPanax Notoginsengtop =NULL; -  the     } +  A     //creates a chain stack with the specified data element, with only one element of the chain the      PublicLinkstack (T element) { +  -top =NewNode (element,NULL); $size++; $  -     } -  the     //returns the length of the link stack -      Public intLength () {Wuyi  the         returnsize; -  Wu     } -  About     //into the stack $      Public voidpush (T element) { -  -         //Point top to the newly created element, and the next reference of the new element points to the original top element of the stack -top =NewNode (element, top); Asize++; +  the     } -  $     //out of the stack the      PublicT Pop () { the  theNode OldTop =top; the         //let the top reference point to the next element of the top element of the original stack -top =Top.next; in         //releases the next reference to the top element of the original stack theOldtop.next =NULL; thesize--; About         returnOldtop.data; the  the     } the  +     //accesses the top element of the stack without deleting the top element of the stack -      PublicT Peek () { the Bayi         returnTop.data; the  the     } -  -     //determine if the link stack is an empty stack the      Public Booleanempty () { the  the         returnSize = = 0; the  -     } the  the     //Please empty chain stack the      Public voidClear () {94  thetop =NULL; theSize = 0; the 98     } About  -      PublicString toString () {101 102         //when the link stack is an empty stack103         if(Empty ()) {104  the             return"[]";106 107}Else {108 109StringBuilder SB =NewStringBuilder ("["); the              for(Node current = top; Current! =NULL; Current =current.next) {111  theSb.append (current.data.toString () + ",");113  the             } the  the             intLen =sb.length ();117             returnSb.delete (Len-2, Len). Append ("]"). toString ();118         }119  -     }121 122}

Test class:

1  PackageCom.ietree.basic.datastructure.stack;2 3 /**4 * Created by Ietree5 * 2017/4/296  */7  Public classLinkstacktest {8 9      Public Static voidMain (string[] args) {Ten  Onelinkstack<string> stack =NewLinkstack<string>(); A  -Stack.push ("AAAA"); -Stack.push ("BBBB"); theStack.push ("CCCC"); -Stack.push ("dddd"); - System.out.println (stack); -  +SYSTEM.OUT.PRINTLN ("Access stack top element:" +Stack.peek ()); -  +System.out.println ("First pop-up stack top element:" +Stack.pop ()); A  atSystem.out.println ("Second pop-up stack top element:" +Stack.pop ()); -  -System.out.println ("Stack after two pops:" +stack); -  -     } -  in}

Program output:

[dddd, CCCC, BBBB, AAAA] access the top element of the stack: dddd first pop-up top element: dddd The second pop-up of the top element: CCCC two times after pop stack: [bbbb, AAAA]

The implementation of the chain-stack storage structure of Java stack