Java Language Implementation Tree

The node class is first defined to store the contents of each node:

 Public classNode {//Key Words    Private intKeyData; //Other data    Private intOtherdata; //left dial hand node    PrivateNode Leftnode; //Right child node    PrivateNode Rightnode;  PublicNode (intKeyData,intotherdate) {         This. KeyData =KeyData;  This. Otherdata =otherdate; }     Public intGetkeydata () {returnKeyData; }     Public voidSetkeydata (intkeyData) {         This. KeyData =KeyData; }     PublicNode Getleftnode () {returnLeftnode; }     Public voidSetleftnode (Node leftnode) { This. Leftnode =Leftnode; }     Public intGetotherdata () {returnOtherdata; }     Public voidSetotherdata (intotherdata) {         This. Otherdata =Otherdata; }     PublicNode Getrightnode () {returnRightnode; }     Public voidSetrightnode (Node rightnode) { This. Rightnode =Rightnode; }    //Display Method     Public voiddisplay () {System.out.println (KeyData+ "," +otherdata); }        }

Then define a tree class and use the pre-order traversal, the middle sequence traversal, and the post-order traversal

 Public classTree {//Root    PrivateNode Root; //Insert Method     Public voidInsertintKeyData,intotherdata) {Node NewNode=NewNode (KeyData, otherdata); //If there are no nodes,        if(Root = =NULL) {root=NewNode; } Else{Node current=Root;            Node parent;  while(true) {Parent=Current ; if(KeyData <Current.getkeydata ()) { Current=Current.getleftnode (); if(Current = =NULL) {Parent.setleftnode (NewNode); return; }                } Else{ Current=Current.getrightnode (); if(Current = =NULL) {Parent.setrightnode (NewNode); return; }                }            }        }    }    //Find Method     PublicNode Find (intkeyData) {Node current=Root;  while(Current.getkeydata ()! =keyData) {            if(KeyData <Current.getkeydata ()) { Current=Current.getleftnode (); } Else{ Current=Current.getrightnode (); }            if(Current = =NULL) {                return NULL; }        }        returnCurrent ; }    //Modify Method     Public voidChangeintKeyData,intnewotherdata) {Node FindNode=find (KeyData);    Findnode.setotherdata (Newotherdata); }    //First Order Traversal     Public voidPreorder (node node) {if(Node! =NULL) {node.display ();            Preorder (Node.getleftnode ());        Preorder (Node.getrightnode ()); }    }    //Middle Sequence Traversal     Public voidinorder (node node) {if(Node! =NULL) {inorder (Node.getleftnode ());            Node.display ();        Inorder (Node.getrightnode ()); }    }    //Post-post traversal     Public voidEndorder (node node) {if(Node! =NULL) {Endorder (Node.getleftnode ());            Endorder (Node.getrightnode ());        Node.display (); }    }     PublicNode Getroot () {returnRoot; }}

Test:

Tree tree =NewTree (); Tree.insert (80, 80); Tree.insert (49, 49); Tree.insert (42, 42); Tree.insert (30, 30); Tree.insert (45, 45); Tree.insert (90, 90); Tree.insert (150, 150); Tree.insert (130, 130); Tree.insert (82, 82); System.out.println ("Pre-order Traversal:");        Tree.preorder (Tree.getroot ()); System.out.println ("Middle sequence Traversal:");        Tree.inorder (Tree.getroot ()); System.out.println ("Post-post traversal:"); Tree.endorder (Tree.getroot ());

Java Language Implementation Tree