java_IO_1

1public class DirStudy {
2    public static void main(String[] args) {
3        File file = new File("F:/EclipseWorkspace/Java300/temp/test");
4        //mkdir 父目录中又不存在的就创建失败  若已存在也创建失败  
5        boolean flag = file.mkdir();
6        System.out.println(flag);
7        //mkdirs 会将文件链中不存在的目录都拿创建  推荐使用mkdirs
8        flag = file.mkdirs();
9        System.out.println(flag);
10    }
11}

false
true

1File file = new File("F:/EclipseWorkspace/Java300");
2        //返回该目录下的文件或目录的字符串名称  只返回一层
3        String[] subString  = file.list();
4        for(String temp:subString) {
5            System.out.println(temp);
6        }
7        
8        File[] subFile  = file.listFiles();
9        for(File temp:subFile) {
10            System.out.println(temp.getPath());
11        }

.classpath
.project
.settings
bin
src
temp
F:\EclipseWorkspace\Java300\.classpath
F:\EclipseWorkspace\Java300\.project
F:\EclipseWorkspace\Java300\.settings
F:\EclipseWorkspace\Java300\bin
F:\EclipseWorkspace\Java300\src
F:\EclipseWorkspace\Java300\temp

递归打印目录下所有内容：

1public static void printPath(File file, int deep) {
2        for (int i = 0; i < deep; i++) {
3            System.out.print("-");
4        }
5        System.out.println(file.getAbsolutePath());
6        if (file == null || !file.exists()) {
7            return;
8        } else if (file.isDirectory()) {
9            File[] temp = file.listFiles();
10            for (File t : temp) {
11                printPath(t, deep + 1);
12            }
13        }
14    }

输出：

1F:\EclipseWorkspace\Java300
2-F:\EclipseWorkspace\Java300\.classpath
3-F:\EclipseWorkspace\Java300\.project
4-F:\EclipseWorkspace\Java300\.settings
5--F:\EclipseWorkspace\Java300\.settings\org.eclipse.jdt.core.prefs
6-F:\EclipseWorkspace\Java300\bin
7--F:\EclipseWorkspace\Java300\bin\ioStudy
8---F:\EclipseWorkspace\Java300\bin\ioStudy\DirStudy.class
9---F:\EclipseWorkspace\Java300\bin\ioStudy\IOstudy1.class
10--F:\EclipseWorkspace\Java300\bin\test
11---F:\EclipseWorkspace\Java300\bin\test\stringTest
12----F:\EclipseWorkspace\Java300\bin\test\stringTest\ArrayCopy1.class
13----F:\EclipseWorkspace\Java300\bin\test\stringTest\MyArrayList.class
14----F:\EclipseWorkspace\Java300\bin\test\stringTest\MyHashMap.class
15----F:\EclipseWorkspace\Java300\bin\test\stringTest\Node.class
16----F:\EclipseWorkspace\Java300\bin\test\stringTest\TestBubbleSort.class
17----F:\EclipseWorkspace\Java300\bin\test\stringTest\TestCollection.class
18----F:\EclipseWorkspace\Java300\bin\test\stringTest\TestString.class
19-F:\EclipseWorkspace\Java300\src
20--F:\EclipseWorkspace\Java300\src\ioStudy
21---F:\EclipseWorkspace\Java300\src\ioStudy\DirStudy.java
22---F:\EclipseWorkspace\Java300\src\ioStudy\IOstudy1.java
23--F:\EclipseWorkspace\Java300\src\test
24---F:\EclipseWorkspace\Java300\src\test\stringTest
25----F:\EclipseWorkspace\Java300\src\test\stringTest\ArrayCopy1.java
26----F:\EclipseWorkspace\Java300\src\test\stringTest\MyArrayList.java
27----F:\EclipseWorkspace\Java300\src\test\stringTest\MyHashMap.java
28----F:\EclipseWorkspace\Java300\src\test\stringTest\TestBubbleSort.java
29----F:\EclipseWorkspace\Java300\src\test\stringTest\TestCollection.java
30----F:\EclipseWorkspace\Java300\src\test\stringTest\TestString.java
31-F:\EclipseWorkspace\Java300\temp
32--F:\EclipseWorkspace\Java300\temp\test

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