// 设定叶节点图标Icon leafIcon = new ImageIcon(TreeViewPanel.class .getResource("/leaf.gif"));// 设定关闭状态节点图标Icon closedIcon = new ImageIcon(TreeViewPanel.class .getResource("/close.gif"));// 设定打开状态节点图标Icon openIcon = new ImageIcon(TreeViewPanel.class .getResource("/open.gif"));// 取得树的渲染器DefaultTreeCellRenderer renderer = (DefaultTreeCellRenderer) tree .getCellRenderer();// 设定叶节点图标renderer.setLeafIcon(leafIcon);// 设定关闭状态节点图标renderer.setClosedIcon(closedIcon);// 设定打开状态节点图标renderer.setOpenIcon(openIcon);但这样灵活性不高，如我想每层的图标都不一样就不能使用这种方法了，我想要的效果如下：
这时我们只有扩展DefaultTreeCellRenderer创建自己的树节点渲染器，我创建的渲染器代码如下：
package com.sitinspring.common.render;import java.awt.Component;import javax.swing.Icon;import javax.swing.ImageIcon;import javax.swing.JTree;import javax.swing.tree.DefaultMutableTreeNode;import javax.swing.tree.DefaultTreeCellRenderer;import javax.swing.tree.TreeNode;
/**
* 树节点渲染器 * @author: sitinspring(junglesong@gmail.com) * @date: 2008-2-12
*/public class TreeNodeRenderer extends DefaultTreeCellRenderer{
private static final long serialVersionUID = 8532405600839140757L; // 數據庫圖標,頂層節點用 private static final Icon databaseIcon = new ImageIcon(TreeNodeRenderer.class .getResource("/database.gif")); // 表圖標,第三層節點用 private static final Icon tableIcon = new ImageIcon(TreeNodeRenderer.class .getResource("/leaf.gif")); // 表空間關閉狀態圖標,關閉狀態的第二層節點用 private static final Icon tableSpaceCloseIcon = new ImageIcon(TreeNodeRenderer.class .getResource("/close.gif")); // 表空間關閉狀態圖標,打開狀態的第二層節點用 private static final Icon tableSpaceOpenIcon = new ImageIcon(TreeNodeRenderer.class .getResource("/open.gif")); public Component getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded, boolean leaf, int row,
boolean hasFocus){
super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf, row, hasFocus); // 取得節點 DefaultMutableTreeNode node=(DefaultMutableTreeNode)value; // 取得路徑 TreeNode[] paths = node.getPath(); // 按路径层次赋予不同的图标 if (paths.length == 3) { setIcon(tableIcon); }else if(paths.length == 2){ // 按展開情況再賦予不同的圖標 if(expanded){ setIcon(tableSpaceOpenIcon);
} else{ setIcon(tableSpaceCloseIcon); } } else if(paths.length == 1){ setIcon(databaseIcon); } return this; }}使用这个渲染器使用以下代码就行了：
tree.setCellRenderer(new TreeNodeRenderer());以上。