Double-stranded collection Add Delete algorithm

To add a delete algorithm to a double-stranded collection:

 PackageCom.linkes; Public  class mylinkelist {/** * More information Welcome to the Kay Academy website: http://kaige123.com * @author Small Mo * * /** * List of linked lists He is in the double chain to carry out the reference to the home, the benefits can be known to the house and the next who * conducive to modification, can be deleted from the beginning of the data can also be deleted from the tail. * Can be removed from the middle specified location. */ PrivateObject[] Shou;PrivateObject[] Wei;//Default Add Method Public   void add(Object obj) {if(Shou = =NULL) {//Header null on new good space 1th and third put null a second put in the data passed inShou =NewObject[] {NULLObjNULL};wei = Shou;//Put the tail point to the header}Else{//If the header has data, then the new good length of 3 space //Put Wei into the first point to the home, the second puts the current data, the third is nullobject[] Objs =NewObject[] {wei, obj,NULL};wei[2] = OBJS;//The third point of the tail points to the ObjsWei = objs;//objs updated to tail}}//Add the method from the back Public   void addlast(Object obj) {Add (obj);}//Add the method from the front Public   void addfirst(Object obj) {if(Shou = =NULL) {Shou =NewObject[] {NULLObjNULL};wei = Shou;}Else{object[] Objs =NewObject[] {NULL, obj, Shou};shou[0] = Objs;shou = Objs;}}//Delete all methods Public   void removeall(int delall) {if(Delall = =0) {Wei =NULL;//Direct making empty all deletedShou =NULL; System.out.println ("Clear Complete");}Else{Try{Throw NewException ("Delete failed!" Delall needs to be ' 0 ' ");}Catch(Exception e) {E.printstacktrace ();}}}//Remove the method from the back Public   Object removelast() {Object obj =NULL;if(Wei = =NULL) {//No tail so direct return false return false;}// Do you have a home if(wei[0] ==NULL) {//If there is no direct tail-to-head system because no home means there is only one dataWei =NULL; shou =NULL;}Else{//Have a home then give the data in the tail 1 to objobj = wei[1];wei = (object[]) wei[0];//tail pointing to the rear subscript 0wei[2] =NULL;}returnobj;}//Remove the method from the front Public   Object removefirst() {Object obj =NULL; obj = shou[1];if(Shou = =NULL) {return false;}if(shou[2] ==NULL) {Wei =NULL; shou =NULL;}Else{Shou = (object[]) shou[2];shou[0] =NULL;}returnobj;}//Remove the method from the middle Public   boolean remove(Object obj) {object[] objs = Shou; while(true) {//Look up and down home //Data passed in is not equal to OBJS current data if(Obj.equals (objs[1])) { Break;//If that's the case, it's a bounce-out loop .}//If the data passed in is not current data then list theOBJS = (object[]) objs[2];if(Objs = =NULL) {//If there is no more, then jump out of the loop  Break;}}if(Objs = =NULL) {return false;}if(Objs = = Shou) {//Ask whether to delete headerRemovefirst ();}Else if(Objs = = Wei) {//Is not deleted tailRemovelast ();}Else{//Split the current data into home and homeobject[] Shang = (object[]) objs[0];object[] Xia = (object[]) objs[2];shang[2] = Xia;//The home of the subscript 2 cited the home dataxia[0] = Shang;//The next subscript 0 of the home cited the home data}return true;}PrivateObject[] dq =NULL;//Use Hashnext to ask for data retrieval Public   boolean hashnext() {if(dq = =NULL) {dq = shou;if(dq = =NULL) {return false;}return true;} dq = (object[]) dq[2];if(dq = =NULL) {return false;}return true;}//Use next to get the value Public   Object Next() {returndq[1];}}

Test class:

Ackage Com.linkes; Public  class Test {Public   static void main(string[] args) {Mylinkelist Linke =NewMylinkelist (); Linke.add ("a"); Linke.addlast ("B"); Linke.addfirst ("C"); Linke.addfirst ("D"); Linke.addfirst ("E"); Linke.addfirst ("F"); Linke.addfirst ("G"); Linke.removeall (1); while(Linke.hashnext ()) {System.out.println (linke). Next ());}}}

Double-stranded collection Add Delete algorithm