How to use

createNewFile

method

in

java.io.File

 String path = "C:" + File.separator + "hello" + File.separator + "hi.txt";
// Use relative path for Unix systems
File f = new File(path);

f.getParentFile().mkdirs(); 
f.createNewFile();

 File yourFile = new File("score.txt");
yourFile.createNewFile(); // if file already exists will do nothing 
FileOutputStream oFile = new FileOutputStream(yourFile, false);

private static boolean createOrExistsFile(final File file) {
  if (file == null) return false;
  if (file.exists()) return file.isFile();
  if (!createOrExistsDir(file.getParentFile())) return false;
  try {
    return file.createNewFile();
  } catch (IOException e) {
    e.printStackTrace();
    return false;
  }
}

public static void updateTerm(long term) throws Exception {
  File file = new File(META_FILE_NAME);
  if (!file.exists() && !file.getParentFile().mkdirs() && !file.createNewFile()) {
    throw new IllegalStateException("failed to create meta file");
  }
  try (FileOutputStream outStream = new FileOutputStream(file)) {
    // write meta
    meta.setProperty("term", String.valueOf(term));
    meta.store(outStream, null);
  }
}

public static void main(String[] args) throws IOException {
  // trying FileLock mechanics in different processes
  File file = new File("tmp.lock");
  file.createNewFile();
  FileChannel channel = new RandomAccessFile(file, "r").getChannel();
  boolean shared = true;
  FileLock lock1 = channel.tryLock(0, Long.MAX_VALUE, shared);
  System.out.println("locked " + lock1);
  System.in.read();
  System.out.println("release " + lock1);
  lock1.release();
}

public static File createFile(String fileName) throws IOException {
  File file = null;
  file = new File(fileName);
  if (!file.exists()) {
    file.createNewFile();
  }
  writeToFile(file, getRandomWordSet());
  return file;
}

 public static void copyFile( File from, File to ) throws IOException {

  if ( !to.exists() ) { to.createNewFile(); }

  try (
    FileChannel in = new FileInputStream( from ).getChannel();
    FileChannel out = new FileOutputStream( to ).getChannel() ) {

    out.transferFrom( in, 0, in.size() );
  }
}

public static File createFileIfNotExist(File file) {
  if (!file.exists()) {
    // 创建父目录
    file.getParentFile().mkdirs();
    try {
      file.createNewFile();
    } catch (IOException e) {
      throw new RuntimeException("create file[" + file.getAbsolutePath() + "] failed!", e);
    }
  }
  return file;
}

 @CanIgnoreReturnValue
 private File newFile(String name) throws IOException {
  File file = new File(rootDir, name);
  file.createNewFile();
  return file;
 }
}

private void writeOutEnhancedClass(byte[] enhancedBytecode, File file) {
  try {
    if ( file.delete() ) {
      if ( !file.createNewFile() ) {
        logger.error( "Unable to recreate class file [" + file.getName() + "]" );
    FileOutputStream outputStream = new FileOutputStream( file, false );
    try {
      outputStream.write( enhancedBytecode );
        outputStream.close();

 ByteArrayOutputStream bytes = new ByteArrayOutputStream();
_bitmapScaled.compress(Bitmap.CompressFormat.JPEG, 40, bytes);

//you can create a new file name "test.jpg" in sdcard folder.
File f = new File(Environment.getExternalStorageDirectory()
            + File.separator + "test.jpg");
f.createNewFile();
//write the bytes in file
FileOutputStream fo = new FileOutputStream(f);
fo.write(bytes.toByteArray());

// remember close de FileOutput
fo.close();

public static void main(String[] args) throws IOException {
  String path = getJarLocation(FileUtil.class);
  System.out.println(path);
  new File(path, "test.txt").createNewFile();
  System.out.println(new File(path).canWrite());
  System.out.println(new File(path).getAbsolutePath());
}

public static void createInitializeFile(File dir) throws IOException {
  File initFile = new File(dir, "initialize");
  if (!initFile.exists()) {
    Assert.assertTrue(initFile.createNewFile());
  }
}

public static void createFilesByPath(File baseDir, String... files) throws IOException {
  for (String file : files) {
    if (file.endsWith("/")) {
      File file1 = new File(baseDir, file);
      file1.mkdirs();
    } else {
      File file1 = new File(baseDir, file);
      file1.getParentFile().mkdirs();
      file1.createNewFile();
    }
  }
}

void writeInputStream(String filename, InputStream inputStream) throws IOException {
 File file = new File(TEMP_DIR + filename);
 file.createNewFile();
 try (OutputStream outputStream = new FileOutputStream(file)) {
  byte[] buffer = new byte[1024];
  int bytesRead;
  while ((bytesRead = inputStream.read(buffer)) != -1) {
   outputStream.write(buffer, 0, bytesRead);
  }
 }
}

public static void writeToFile( File target, String text, boolean append ) throws IOException
{
  if ( !target.exists() )
  {
    Files.createDirectories( target.getParentFile().toPath() );
    //noinspection ResultOfMethodCallIgnored
    target.createNewFile();
  }
  try ( Writer out = new OutputStreamWriter( new FileOutputStream( target, append ), StandardCharsets.UTF_8 ) )
  {
    out.write( text );
  }
}

public static File createFileIfNotExist(File file) {
  if (!file.exists()) {
    // 创建父目录
    file.getParentFile().mkdirs();
    try {
      file.createNewFile();
    } catch (IOException e) {
      throw new RuntimeException("create file[" + file.getAbsolutePath() + "] failed!", e);
    }
  }
  return file;
}

@Test
public void testWithANonMatchingFile() throws IOException, InterruptedException {
 watcher.watch();
 // Initial deployment
 assertWaitUntil(() -> deploy.get() == 1);
 File file = new File(root, "foo.nope");
 file.createNewFile();
 Thread.sleep(500);
 assertThat(undeploy.get()).isEqualTo(0);
 assertThat(deploy.get()).isEqualTo(1);
}

@Test
public void testDelete() throws Exception {
 assertThat(file.createNewFile()).isTrue();
 atomicFile.delete();
 assertThat(file.exists()).isFalse();
}

 //create a file to write bitmap data
File f = new File(context.getCacheDir(), filename);
f.createNewFile();

//Convert bitmap to byte array
Bitmap bitmap = your bitmap;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bitmap.compress(CompressFormat.PNG, 0 /*ignored for PNG*/, bos);
byte[] bitmapdata = bos.toByteArray();

//write the bytes in file
FileOutputStream fos = new FileOutputStream(f);
fos.write(bitmapdata);
fos.flush();
fos.close();