Java如何判断文件或者文件夹是否在？不存在如何创建？

 1 import java.io.File;
 2 import java.io.IOException;
 3 
 4 public class Main {
 5 
 6     public static void main(String[] args) {
 7 
 8         File file = new File("d:\\test_file.txt");
 9         Main.judeFileExists(file);
10 
11         File dir = new File("d:\\test_dir");
12         Main.judeDirExists(dir);
13     }
14 
15     // 判断文件是否存在
16     public static void judeFileExists(File file) {
17 
18         if (file.exists()) {
19             System.out.println("file exists");
20         } else {
21             System.out.println("file not exists, create it ...");
22             try {
23                 file.createNewFile();
24             } catch (IOException e) {
25                 // TODO Auto-generated catch block
26                 e.printStackTrace();
27             }
28         }
29 
30     }
31 
32     // 判断文件夹是否存在
33     public static void judeDirExists(File file) {
34 
35         if (file.exists()) {
36             if (file.isDirectory()) {
37                 System.out.println("dir exists");
38             } else {
39                 System.out.println("the same name file exists, can not create dir");
40             }
41         } else {
42             System.out.println("dir not exists, create it ...");
43             file.mkdir();
44         }
45 
46     }
47 
48 }