虽然可以使用file.delete()轻松删除文件，但要删除的目录必须为空。使用递归可以很容易地做到这一点。例如:

public static void clearFolders(String[] args) {
        for(String st : args){
            File folder = new File(st);
            if (folder.isDirectory()) {
                File[] files = folder.listFiles();
                if(files!=null) { 
                    for(File f: files) {
                        if (f.isDirectory()){
                            clearFolders(new String[]{f.getAbsolutePath()});
                            f.delete();
                        } else {
                            f.delete();
                        }
                    }
                }
            }
        }
    }

在遗留项目中，我需要创建本地Java代码。我创建了类似于Paulitex代码的代码。看到:

public class FileHelper {

   public static boolean delete(File fileOrFolder) {
      boolean result = true;
      if(fileOrFolder.isDirectory()) {
         for (File file : fileOrFolder.listFiles()) {
            result = result && delete(file);
         }
      }
      result = result && fileOrFolder.delete();
      return result;
   } 
}

单元测试:

public class FileHelperTest {

    @Before
    public void setup() throws IOException {
       new File("FOLDER_TO_DELETE/SUBFOLDER").mkdirs();
       new File("FOLDER_TO_DELETE/SUBFOLDER_TWO").mkdirs();
       new File("FOLDER_TO_DELETE/SUBFOLDER_TWO/TEST_FILE.txt").createNewFile();
    }

    @Test
    public void deleteFolderWithFiles() {
       File folderToDelete = new File("FOLDER_TO_DELETE");
       Assert.assertTrue(FileHelper.delete(folderToDelete));
       Assert.assertFalse(new File("FOLDER_TO_DELETE").exists());
    }

}

使用符号链接和上面的代码失败的两种方式…也不知道怎么解决。

方法# 1

运行这个来创建一个测试:

echo test > testfile
mkdir dirtodelete
ln -s badlink dirtodelete/badlinktodelete

下面你可以看到你的测试文件和测试目录:

$ ls testfile dirtodelete
testfile

dirtodelete:
linktodelete

然后运行common -io deleteDirectory()。它崩溃，说文件没有找到。不知道其他例子是怎么做的。Linux的rm命令会简单地删除链接，目录上的rm -r也会删除链接。

Exception in thread "main" java.io.FileNotFoundException: File does not exist: /tmp/dirtodelete/linktodelete

方法# 2

运行这个来创建一个测试:

mkdir testdir
echo test > testdir/testfile
mkdir dirtodelete
ln -s ../testdir dirtodelete/dirlinktodelete

下面你可以看到你的测试文件和测试目录:

$ ls dirtodelete testdir
dirtodelete:
dirlinktodelete

testdir:
testfile

然后运行common -io deleteDirectory()或人们发布的示例代码。它不仅会删除目录，还会删除位于被删除目录之外的testfile。(它隐式地取消对目录的引用，并删除内容)。Rm -r只会删除链接。你需要使用类似这样的方法删除被解引用的文件:"find -L dirtodelete -type f -exec rm {} \;"

$ ls dirtodelete testdir
ls: cannot access dirtodelete: No such file or directory
testdir:

// Java 8的lambda & stream，如果参数是目录

static boolean delRecursive(File dir) {
    return Arrays.stream(dir.listFiles()).allMatch((f) -> f.isDirectory() ? delRecursive(f) : f.delete()) && dir.delete();
}

如果参数是文件或目录

static boolean delRecursive(File fileOrDir) {
    return fileOrDir.isDirectory() ? Arrays.stream(fileOrDir.listFiles()).allMatch((f) -> delRecursive(f)) && fileOrDir.delete() : fileOrDir.delete();
}

一个有堆栈且没有递归方法的解决方案:

File dir = new File("/path/to/dir");
File[] currList;
Stack<File> stack = new Stack<File>();
stack.push(dir);
while (! stack.isEmpty()) {
    if (stack.lastElement().isDirectory()) {
        currList = stack.lastElement().listFiles();
        if (currList.length > 0) {
            for (File curr: currList) {
                stack.push(curr);
            }
        } else {
            stack.pop().delete();
        }
    } else {
        stack.pop().delete();
    }
}

番石榴21.0及以上版本

有一个void deleterecursive (Path Path, RecursiveDeleteOption…)options)会抛出从Guava 21.0开始可用的MoreFiles类的IOException静态方法。

请参阅Javadoc文档:

public static void deleteRecursively(Path path, RecursiveDeleteOption... options) throws IOException Deletes the file or directory at the given path recursively. Deletes symbolic links, not their targets (subject to the caveat below). If an I/O exception occurs attempting to read, open or delete any file under the given directory, this method skips that file and continues. All such exceptions are collected and, after attempting to delete all files, an IOException is thrown containing those exceptions as suppressed exceptions.