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java JTree文件过滤器和文件夹过滤器

我想要一个JTree,它显示我当前目录中所有扩展名仅为“.h”的文件,并且它应该显示所有文件夹,除了一个名为“系统卷信息”的文件夹,在我当前目录中,这是我的代码,还有什么。。更新我需要做什么

import java.awt.BorderLayout;
import java.awt.Container;
import java.io.File;
import java.util.Collections;
import java.util.Vector;

import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;


public class DriveTree extends JPanel
{

    public DriveTree(File dir) 
    {
        setLayout(new BorderLayout());
        JTree tree = new JTree(addNodes(null, dir));
        add(tree);
    }

    DefaultMutableTreeNode addNodes(DefaultMutableTreeNode curTop, File dir)
    {
        String curPath = dir.getPath();
        DefaultMutableTreeNode curDir = new DefaultMutableTreeNode(curPath);
        if (curTop != null)
        {
          curTop.add(curDir);
        }
        Vector ol = new Vector();
        String[] tmp = dir.list();
        for (int i = 0; i < tmp.length; i++)
        ol.addElement(tmp[i]);
        Collections.sort(ol, String.CASE_INSENSITIVE_ORDER);
        File f;
        Vector files = new Vector();
        for (int i = 0; i < ol.size(); i++)
        {
            String thisObject = (String) ol.elementAt(i);
            String newPath;
            if (curPath.equals("."))
            newPath = thisObject;
            else
            newPath = curPath + File.separator + thisObject;
            if ((f = new File(newPath)).isDirectory())
            addNodes(curDir, f);
            else
            files.addElement(thisObject);
        }
       for (int fnum = 0; fnum < files.size(); fnum++)
       curDir.add(new DefaultMutableTreeNode(files.elementAt(fnum)));
       return curDir;
    }

  public static void main(String[] av)
  {

    JFrame frame = new JFrame("Drive View");
    Container cp = frame.getContentPane();
    if (av.length == 0) 
    {
      cp.add(new DriveTree(new File(".")));
    }
    else
    {
      cp.setLayout(new BoxLayout(cp, BoxLayout.X_AXIS));
      for (int i = 0; i < av.length; i++)
      cp.add(new DriveTree(new File(av[i])));
    }
    frame.pack();
    frame.setVisible(true);
    frame.setSize(300,500);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  }
}

共 (3) 个答案

  1. # 1 楼答案

    您可以获取要添加的文件的扩展名,并在此扩展名上进行检查:

    String extension = "";
    
    int i = fileName.lastIndexOf('.');
    if (i > 0 && i < s.length() - 1) {
        extension = fileName.substring(i+1);
    }
    
    if(extension.equals("h"))
    {
       //Add to your tree
    }
    
  2. # 2 楼答案

    利用API。File类提供了从list方法筛选返回结果的功能

    File[] file = dir.listFiles(new FileFilter() {
        @Override
        public boolean accept(File pathname) {
            String name = pathname.getName().toLowerCase();
            return name.endsWith(".h") || (pathname.isDirectory() && !("System Volume Information".equalsIgnoreCase(name)));
        }
    });
    

    用示例更新

    据我所知,这就是你要找的。这可能会改变屏幕上的结果,因为我直接使用了File对象,但是可以通过使用^{}来修复它

    import java.awt.BorderLayout;
    import java.awt.Container;
    import java.io.File;
    import java.io.FileFilter;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collections;
    import java.util.List;
    import java.util.Vector;
    import javax.swing.BoxLayout;
    import javax.swing.JFrame;
    import javax.swing.JPanel;
    import javax.swing.JTree;
    import javax.swing.tree.DefaultMutableTreeNode;
    
    public class DriveTree extends JPanel {
    
        public DriveTree(File dir) {
            setLayout(new BorderLayout());
            JTree tree = new JTree(addNodes(null, dir));
            add(tree);
        }
    
        DefaultMutableTreeNode addNodes(DefaultMutableTreeNode curTop, File dir) {
            String curPath = dir.getPath();
            DefaultMutableTreeNode curDir = new DefaultMutableTreeNode(curPath);
            if (curTop != null) {
                curTop.add(curDir);
            }
    
            List<File> files = new ArrayList<File>(Arrays.asList(dir.listFiles(new FileFilter() {
                @Override
                public boolean accept(File pathname) {
                    String name = pathname.getName().toLowerCase();
                    return name.endsWith(".h") || (pathname.isDirectory() && !("System Volume Information".equalsIgnoreCase(name)));
                }
            })));
    
            Collections.sort(files);
    //        File f;
    //        Vector files = new Vector();
    //        for (int i = 0; i < ol.size(); i++) {
    //            String thisObject = (String) ol.elementAt(i);
    //            String newPath;
    //            if (curPath.equals(".")) {
    //                newPath = thisObject;
    //            } else {
    //                newPath = curPath + File.separator + thisObject;
    //            }
    //            if ((f = new File(newPath)).isDirectory()) {
    //                addNodes(curDir, f);
    //            } else {
    //                files.addElement(thisObject);
    //            }
    //        }
            for (File file : files) {
                if (file.isDirectory()) {
                    addNodes(curDir, file);
                }
            }
            for (File file : files) {
                if (file.isFile()) {
                    curDir.add(new DefaultMutableTreeNode(file));
                }
            }
            return curDir;
        }
    
        public static void main(String[] av) {
    
            JFrame frame = new JFrame("Drive View");
            Container cp = frame.getContentPane();
            if (av.length == 0) {
                cp.add(new DriveTree(new File(".")));
            } else {
                cp.setLayout(new BoxLayout(cp, BoxLayout.X_AXIS));
                for (int i = 0; i < av.length; i++) {
                    cp.add(new DriveTree(new File(av[i])));
                }
            }
            frame.pack();
            frame.setVisible(true);
            frame.setSize(300, 500);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        }
    }
    
  3. # 3 楼答案

    您可以使用FileNameExtensionFilter

    FileNameExtensionFilter filter = new FileNameExtensionFilter(null, "h");
    
    for(//...
        if ((f = new File(newPath)).isDirectory())
            addNodes(curDir, f);
        else if(filter.accept(new File(newPath))) //accept only returns true if the extension matches
            files.addElement(thisObject);