package tree;
import java.io.File;
import java.io.FilenameFilter;
public class DefaultFileNameFileter implements FilenameFilter
{
    @Override
    public boolean accept(File dir, String name)
    {
        return true;
    }
}

package tree;
import java.io.File;
import java.io.FilenameFilter;
public class MavenJavaWebFileNameFilter implements FilenameFilter
{
    private String RootPath = null;
    MavenJavaWebFileNameFilter(String RootPath)
    {
        this.RootPath = RootPath;
    }
    @Override
    public boolean accept(File dir, String name)
    {
        // 该文件不能以点号开头,
        // 也不能以txt文件结尾
        // 文件名称不能是bin
        // 文件名称不能是target
        if (name.startsWith(".") || name.endsWith(".txt"))
        {
            return false;
        }
        // 如果是根目录
        if (RootPath.equals(dir.getAbsolutePath()))
        {
            // 第一级目录下的bin目录,
            // 或者target目录(maven,输出)不是java项目必须目录所以不输出
            if ("bin".equals(name) || "target".equals(name)
                    || "test".equals(name))
            {
                return false;
            }
        }
        return true;
    }
}

package tree;
import java.io.File;
import java.io.FilenameFilter;
public class MyTree
{
    private static String RootPath = null;
    private static MavenJavaWebFileNameFilter mavenJaveWebFileNameFilter = null;
    private static DefaultFileNameFileter defaultFileNameFileter=new DefaultFileNameFileter();
    public static void main(String args[])
    {
        // String path = "E:\\workspace\\Regex";
        // String path = "E:\\workspace_web\\app17a";
        // 通过剪贴板读入目录
        // String path =SysClipboardUtil.getSysClipboardText();
        // 使用当前目录作为目录
        String path = System.getProperty("user.dir");
        // 保存根目录,后续要用到
        RootPath = path;
        mavenJaveWebFileNameFilter = new MavenJavaWebFileNameFilter(RootPath);
        File dir = new File(path);
        switch (args.length)
        {
            case 1 :
                oneArgs(args, dir);
                break;
            default :
                printTreeDir(dir);
                break;
        }
    }
    /**
     * 输入一个参数的情况.
     * 
     * @param args
     *            参数列表
     * @param dir
     *            目录的File对象.
     */
    private static void oneArgs(String[] args, File dir)
    {
        // TODO Auto-generated method stub
        String arg1 = args[0];
        switch (arg1)
        {
            case "f" :
                printTreeFileAndDir(dir, defaultFileNameFileter);
                break;
            case "java" :
                printTreeFileAndDir(dir, mavenJaveWebFileNameFilter);
                break;
            default :
                break;
        }
    }
    /**
     * 打印dir表示的目录的目录树.
     * 
     * @param dir
     *            表示目录的File对象.
     */
    public static void printTreeDir(File dir)
    {
        System.out.println(dir.getAbsolutePath());
        printTreeDir(dir, "", 0);
    }
    /**
     * @param dir
     */
    private static void printTreeDir(File dir, String prefix, int deep)
    {
        if (dir.isDirectory())
        {
            // 生成目录下的子目录列表
            File[] dirList = dir.listFiles(new FilenameFilter()
            {
                @Override
                public boolean accept(File dir, String name)
                {
                    // 该文件是目录,并且不能以点号开头,
                    // 点号开头的一般是隐藏文件
                    return new File(dir, name).isDirectory()
                            && !name.startsWith(".");
                }
            });
            String thisPrefix = "";
            String nextPrefix = "";
            for (int i = 0; i < dirList.length; i++)
            {
                if (deep >= 0)
                {
                    // 如果不是最后一个元素
                    if ((i + 1 < dirList.length))
                    {
                        // 不是最后一个目录都打印这个符号
                        thisPrefix = prefix + "├─";
                        // 下一个打印这符号表示展开目录
                        nextPrefix = prefix + "│ ";
                    } else
                    {
                        // 最后一个子目录项
                        thisPrefix = prefix + "└─";
                        //
                        nextPrefix = prefix + "  ";
                    }
                }
                System.out.println(thisPrefix + dirList[i].getName());
                printTreeDir(dirList[i], nextPrefix, deep + 1);
            }
        }
    }
    /**
     * @param dir
     */
    public static void printTreeFileAndDir(File dir,FilenameFilter fileNameFilter)
    {
        // 打印根目录
        System.out.println(dir.getAbsolutePath());
        printTreeFileAndDir(dir, fileNameFilter,"", 0);
    }
    /**
     * 打印目录树
     * 
     * @param dir
     *            目录
     * @param prefix
     *            前缀,需要打印在文件或者目录之前
     * @param deep
     *            深度
     */
    private static void printTreeFileAndDir(File dir,
            FilenameFilter fileNameFilter, String prefix, int deep)
    {
        // 列出目录下的子目录
        File[] childs = dir.listFiles(fileNameFilter);
        // 遍历子目录
        for (int i = 0; i < childs.length; i++)
        {
            // 本次递归的前缀
            String thisPrefix = "";
            // 下一个递归的前缀
            String nextPrefix = "";
            if (deep >= 0)
            {
                // 如果不是最后一个元素
                if ((i + 1 < childs.length))
                {
                    nextPrefix = prefix + "│ ";
                    thisPrefix = prefix + "├─";
                } else
                {
                    nextPrefix = prefix + "  ";
                    thisPrefix = prefix + "└─";
                }
            }
            System.out.println(thisPrefix + childs[i].getName());
            if (childs[i].isDirectory())
            {
                printTreeFileAndDir(childs[i], fileNameFilter, nextPrefix,
                        deep + 1);
            }
        }
    }
}

package hello;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/HelloWorldServlet")
public class HelloWorldServlet extends HttpServlet
{
    private static final long serialVersionUID = 1L;
    protected void doGet(HttpServletRequest request,
        HttpServletResponse response)
        throws ServletException,IOException
    {
        response.setContentType("text/html,charset=utf-8;");
        PrintWriter writer = response.getWriter();
        writer.println(
            "<html><head><title>helloworld</title></head>"
                + "<body><h2>HelloWorld</h2></body>"
                + "</html>");
    }
}