Android how to Clear App Data Programatically

public class MainActivity extends AppCompatActivity {

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

//clearApplicationData();  ---Method 1
/* ((ActivityManager)MainActivity.this.getSystemService(ACTIVITY_SERVICE)) .clearApplicationUserData();*/ --- Method 2 // deleteAppData(); ---- Method 3
}

private void deleteAppData() {
try {
// clearing app data String packageName = getApplicationContext().getPackageName();
Runtime runtime = Runtime.getRuntime();
runtime.exec("pm clear "+packageName);

} catch (Exception e) {
e.printStackTrace();
} }


public void clearApplicationData() {
File cacheDirectory = getCacheDir();
File applicationDirectory = new File(cacheDirectory.getParent());
if (applicationDirectory.exists()) {
String[] fileNames = applicationDirectory.list();
for (String fileName : fileNames) {
if (!fileName.equals("lib")) {
deleteFile(new File(applicationDirectory, fileName));
}
}
}
}


public static boolean deleteFile(File file) {
boolean deletedAll = true;
if (file != null) {
if (file.isDirectory()) {
String[] children = file.list();
for (int i = 0; i < children.length; i++) {
deletedAll = deleteFile(new File(file, children[i])) && deletedAll;
}
} else {
deletedAll = file.delete();
}
}

return deletedAll;
}

}