java实现二叉树层次遍历

import java.util.ArrayList;

public class TreeNode {
private TreeNode leftNode;
private TreeNode rightNode;
private String nodeName;
public TreeNode getLeftNode() {
return leftNode;
}

public void setLeftNode(TreeNode leftNode) {
this.leftNode = leftNode;
}

public TreeNode getRightNode() {
return rightNode;
}

public void setRightNode(TreeNode rightNode) {
this.rightNode = rightNode;
}

public String getNodeName() {
return nodeName;
}

public void setNodeName(String nodeName) {
this.nodeName = nodeName;
}
public static int level=0;

public static void findNodeByLevel(ArrayList<TreeNode> nodes){
if(nodes==null||nodes.size()==0){
return ;
}
level++;
ArrayList<TreeNode> temp = new ArrayList();
for(TreeNode node:nodes){
System.out.println(&qu