二叉树搭建及先序、中序、后序遍历(JAVA)

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                 A
              /      \

         B             C

       /    \                \
   D        E               F

package binaryTree;

public class BinaryTree {
	
	public Treenode createBinaryTree()
	{
		Treenode a=new Treenode(0, "A");
		Treenode b=new Treenode(1, "B");
		Treenode c=new Treenode(2, "C");
		Treenode d=new Treenode(3, "D");
		Treenode e=new Treenode(4, "E");
		Treenode f=new Treenode(5, "F");
		a.setLeftChild(b);
		a.setRightChild(c);
		b.setLeftChild(d);
		b.setRightChild(e);
		c.setRightChild(f);
		return a;
	}
	
	public static void main(String args[])
	{
		BinaryTree binaryTree =new BinaryTree();
		Treenode root=binaryTree.createBinaryTree();
		//binaryTree.preOrder(root);
		//binaryTree.midOrder(root);
		binaryTree.pastOrder(root);
		System.out.println(binaryTree.getHeight(root));
	}
	
	public void preOrder(Treenode root)//先序
	{
		System.out.println(root.data);
		if(root.leftChild!=null)
		preOrder(root.leftChild);
		if(root.rightChild!=null)
		preOrder(root.rightChild);
	}
	
	public void midOrder(Treenode root)//中序
	{
		if(root.leftChild!=null)
		midOrder(root.leftChild);
		System.out.println(root.data);
		if(root.rightChild!=null)
		midOrder(root.rightChild);
	}
	public void pastOrder(Treenode root)//后序
	{
		if(root.leftChild!=null)
			pastOrder(root.leftChild);
		if(root.rightChild!=null)
			pastOrder(root.rightChild);
		System.out.println(root.data);
	}
	public int getHeight(Treenode node)
	{
		if(node==null)
			return 0;
		else
		{
			int i=getHeight(node.leftChild);
			int j=getHeight(node.rightChild);
			return i<j?j+1:i+1;
		}
			
		
	}
}

class Treenode {
	
	String data;
	int index;
	Treenode leftChild;
	Treenode rightChild;
	public String getData() {
		return data;
	}
	public void setData(String data) {
		this.data = data;
	}
	public int getIndex() {
		return index;
	}
	public void setIndex(int index) {
		this.index = index;
	}
	public Treenode getLeftChild() {
		return leftChild;
	}
	public void setLeftChild(Treenode leftChild) {
		this.leftChild = leftChild;
	}
	public Treenode getRightChild() {
		return rightChild;
	}
	public void setRightChild(Treenode rightChild) {
		this.rightChild = rightChild;
	}
	public Treenode(int index,String data)
	{
		setData(data);
		setIndex(index);
		setLeftChild(null);
		setRightChild(null);
	}
}