Double-stranded collection Add Delete algorithm

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

Package com.linkes;PublicClassmylinkelist {/** * More information Welcome to the Kay Academy website: http://kaige123.com *@author Small Foam * */** * 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. */Private object[] Shou;Private object[] Wei;Default Add MethodPublicvoidAdd(Object obj) {if (Shou = =NULL) {The first null is the new good space 1th and the third place null the second put the data passed in Shou =New object[] {NULL, obj,Null};wei = Shou;Point the tail to the header}else {If the header has data, then the new 3-length spacePut Wei into the first point to the home, the second into the current data, the third is nullobject[] Objs =New object[] {wei, obj,Null};wei[2] = OBJS;The third of the tail points to Objswei = OBJS;OBJS updated to Tail}}Add a method from the backPublicvoidAddLast(Object obj) {Add (obj);}Add a method from the frontPublicvoidAddFirst(Object obj) {if (Shou = =NULL) {Shou =New object[] {NULL, obj,Null};wei = Shou;}else {object[] Objs =New object[] {NULL, obj, Shou};shou[0] = Objs;shou = Objs;}}Delete all methodsPublicvoidRemoveAll(int Delall) {if (Delall = =0) {Wei =NullThe direct production of empty is all deleted Shou =Null System.out.println ("Clear Complete");}else {try {ThrowNew Exception ("Delete failed!" Delall need to be ' 0 ' ");}catch (Exception e) {e.printstacktrace ();}}}Remove a method from the backPublic ObjectRemovelast() {Object obj =Nullif (Wei = =NULL) {No tail so directly returns falseReturnfalse;}Do you have a homeif (wei[0] = =NULL) {If there is no direct tail with the first system empty because no home means there is only one data Wei =Null;shou =null;}else {If you have a home then give the data in the tail 1 to Objobj = wei[1];wei = (object[]) wei[0];The tail points to the trailing subscript 0wei[2] =null;}return obj;}Remove a method from the frontPublic ObjectRemovefirst() {Object obj =Null;obj = shou[1];if (Shou = =NULL) {Returnfalse;}if (shou[2] = =NULL) {Wei =Null;shou =null;}else {Shou = (object[]) shou[2];shou[0] =null;}return obj;}Remove a method from the middlePublicBooleanRemove(Object obj) {object[] objs = Shou;while (True) {Look up and down homeData passed in is not equal to OBJS current dataif (Obj.equals (objs[1])) {BreakIf that's the case, it's the bounce loop.If the data passed in is not the current data then list OBJS = (object[]) objs[2];if (Objs = =NULL) {If there's no more, then jump out of the loop.Break;}}if (Objs = =NULL) {Returnfalse;}if (Objs = = Shou) {Ask whether to delete the header Removefirst ();}Elseif (Objs = = Wei) {is not to delete tail removelast ();}else {Split the current data into home and home object[] Shang = (object[]) objs[0];object[] Xia = (object[]) objs[2];shang[2] = Xia;The home of the subscript 2 cited the next data xia[0] = Shang;The next subscript 0 quoted the home data}Returntrue;}Private object[] dq =NullQuery data retrieval with HashnextPublicBooleanHashnext() {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() {return dq[1];}}       

Test class:

Ackage Com.linkes; public class test {public static void main new mylinkelist (); Linke.add ( "a"); Linke.addlast ( "B"); Linke.addfirst ( "F"); Linke.addfirst ( 1);                

Double-stranded collection add Delete algorithm