如何在 Java 中获取 JTree 中根节点的深度?
要在 Java 中获取 JTree 中根节点的深度,请使用 getDepth() 方法。假设我们的根节点是“node”,因此,我们将像这样获取根节点的深度 −
node.getDepth();
以下是一个获取根节点深度的示例 −
示例
package my;
import javax.swing.JFrame;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
public class SwingDemo {
public static void main(String[] args) throws Exception {
JFrame frame = new JFrame("Demo");
DefaultMutableTreeNode node = new DefaultMutableTreeNode("Website");
DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("Videos"); DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Tutorials");
DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("QA");
DefaultMutableTreeNode node4 = new DefaultMutableTreeNode("Tools");
node.add(node1); node.add(node2);
node.add(node3);
node.add(node4);
DefaultMutableTreeNode one = new DefaultMutableTreeNode("PHP Videos");
DefaultMutableTreeNode two = new DefaultMutableTreeNode("HTML5 Videos");
DefaultMutableTreeNode three = new DefaultMutableTreeNode("Blockchain Videos");
DefaultMutableTreeNode four = new DefaultMutableTreeNode("Java");
DefaultMutableTreeNode five = new DefaultMutableTreeNode("DBMS");
DefaultMutableTreeNode six = new DefaultMutableTreeNode("CSS");
DefaultMutableTreeNode seven = new DefaultMutableTreeNode("MongoDB");
DefaultMutableTreeNode eight = new DefaultMutableTreeNode("Python QA");
DefaultMutableTreeNode nine = new DefaultMutableTreeNode("jQuery QA");
DefaultMutableTreeNode ten = new DefaultMutableTreeNode("Photo Editing Tool");
node1.add(one);
node1.add(two);
node1.add(three); node2.add(four);
node2.add(five); node2.add(six); node2.add(seven);
node3.add(eight);
node3.add(nine);
node4.add(ten);
JTree tree = new JTree(node);
for (int i = 0; i < tree.getRowCount(); i++) {
tree.expandRow(i);
}
tree.putClientProperty("JTree.lineStyle", "Angled");
System.out.println("Number of children of node1 (Videos) = " + node1.getChildCount());
System.out.println("Number of children of node2 (Tutorials) = " + node2.getChildCount());
System.out.println("Number of children of node3 (QA) = " + node3.getChildCount());
System.out.println("Number of children of node4 (Tools) = " + node4.getChildCount());
System.out.println("Depth of Tree = " + node.getDepth());
tree.setRowHeight(25);
frame.add(tree);
frame.setSize(600,450);
frame.setVisible(true);
}
}输出如下,在控制台中显示根节点的深度 −

以下是我们JTree−

广告
数据结构
网络
RDBMS
操作系统
Java
iOS
HTML
CSS
Android
Python
C 语言编程
C++
C#
MongoDB
MySQL
Javascript
PHP