Java tutorial
/* * Copyright (C) 2015 Federico Iosue (federico.iosue@gmail.com) * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package it.feio.android.omninotes.utils; import android.content.ContentResolver; import android.content.Context; import android.database.Cursor; import android.net.Uri; import android.os.Build; import android.os.Environment; import android.os.StatFs; import android.provider.MediaStore; import android.text.TextUtils; import android.util.Log; import android.webkit.MimeTypeMap; import android.widget.Toast; import it.feio.android.omninotes.R; import it.feio.android.omninotes.models.Attachment; import org.apache.commons.io.FileUtils; import java.io.*; import java.net.URL; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Locale; public class StorageHelper { public static boolean checkStorage() { boolean mExternalStorageAvailable; boolean mExternalStorageWriteable; String state = Environment.getExternalStorageState(); switch (state) { case Environment.MEDIA_MOUNTED: // We can read and write the media mExternalStorageAvailable = mExternalStorageWriteable = true; break; case Environment.MEDIA_MOUNTED_READ_ONLY: // We can only read the media mExternalStorageAvailable = true; mExternalStorageWriteable = false; break; default: // Something else is wrong. It may be one of many other states, but // all we need // to know is we can neither read nor write mExternalStorageAvailable = mExternalStorageWriteable = false; break; } return mExternalStorageAvailable && mExternalStorageWriteable; } public static String getStorageDir() { // return Environment.getExternalStorageDirectory() + File.separator + // Constants.TAG + File.separator; return Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS).toString(); } public static File getAttachmentDir(Context mContext) { return mContext.getExternalFilesDir(null); } /** * Retrieves the folderwhere to store data to sync notes * * @param mContext * @return */ public static File getDbSyncDir(Context mContext) { File extFilesDir = mContext.getExternalFilesDir(null); File dbSyncDir = new File(extFilesDir, Constants.APP_STORAGE_DIRECTORY_SB_SYNC); dbSyncDir.mkdirs(); if (dbSyncDir.exists() && dbSyncDir.isDirectory()) { return dbSyncDir; } else { return null; } } /** * Create a path where we will place our private file on external * * @param mContext * @param uri * @return */ public static File createExternalStoragePrivateFile(Context mContext, Uri uri, String extension) { // Checks for external storage availability if (!checkStorage()) { Toast.makeText(mContext, mContext.getString(R.string.storage_not_available), Toast.LENGTH_SHORT).show(); return null; } File file = createNewAttachmentFile(mContext, extension); InputStream is; OutputStream os; try { is = mContext.getContentResolver().openInputStream(uri); os = new FileOutputStream(file); copyFile(is, os); } catch (IOException e) { try { is = new FileInputStream(FileHelper.getPath(mContext, uri)); os = new FileOutputStream(file); copyFile(is, os); // It's a path!! } catch (NullPointerException e1) { try { is = new FileInputStream(uri.getPath()); os = new FileOutputStream(file); copyFile(is, os); } catch (FileNotFoundException e2) { Log.e(Constants.TAG, "Error writing " + file, e2); file = null; } } catch (FileNotFoundException e2) { Log.e(Constants.TAG, "Error writing " + file, e2); file = null; } } return file; } public static boolean copyFile(File source, File destination) { try { return copyFile(new FileInputStream(source), new FileOutputStream(destination)); } catch (FileNotFoundException e) { Log.e(Constants.TAG, "Error copying file", e); return false; } } /** * Generic file copy method * * @param is Input * @param os Output * @return True if copy is done, false otherwise */ public static boolean copyFile(InputStream is, OutputStream os) { boolean res = false; byte[] data = new byte[1024]; int len; try { while ((len = is.read(data)) > 0) { os.write(data, 0, len); } is.close(); os.close(); res = true; } catch (IOException e) { Log.e(Constants.TAG, "Error copying file", e); } return res; } public static boolean deleteExternalStoragePrivateFile(Context mContext, String name) { boolean res = false; // Checks for external storage availability if (!checkStorage()) { Toast.makeText(mContext, mContext.getString(R.string.storage_not_available), Toast.LENGTH_SHORT).show(); return false; } File file = new File(mContext.getExternalFilesDir(null), name); file.delete(); return true; } public static boolean delete(Context mContext, String name) { boolean res = false; // Checks for external storage availability if (!checkStorage()) { Toast.makeText(mContext, mContext.getString(R.string.storage_not_available), Toast.LENGTH_SHORT).show(); return false; } File file = new File(name); if (file.isFile()) { res = file.delete(); } else if (file.isDirectory()) { File[] files = file.listFiles(); for (File file2 : files) { res = delete(mContext, file2.getAbsolutePath()); } res = file.delete(); } return res; } public static String getRealPathFromURI(Context mContext, Uri contentUri) { String[] proj = { MediaStore.Images.Media.DATA }; Cursor cursor = mContext.getContentResolver().query(contentUri, proj, null, null, null); if (cursor == null) { return null; } int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA); cursor.moveToFirst(); return cursor.getString(column_index); } public static File createNewAttachmentFile(Context mContext, String extension) { File f = null; if (checkStorage()) { f = new File(mContext.getExternalFilesDir(null), createNewAttachmentName(extension)); } return f; } public static synchronized String createNewAttachmentName(String extension) { Calendar now = Calendar.getInstance(); SimpleDateFormat sdf = new SimpleDateFormat(Constants.DATE_FORMAT_SORTABLE); String name = sdf.format(now.getTime()); name += extension != null ? extension : ""; return name; } public static File createNewAttachmentFile(Context mContext) { return createNewAttachmentFile(mContext, null); } /** * Create a path where we will place our private file on external * * @param mContext * @param uri * @return */ public static File copyToBackupDir(File backupDir, File file) { // Checks for external storage availability if (!checkStorage()) { return null; } if (!backupDir.exists()) { backupDir.mkdirs(); } File destination = new File(backupDir, file.getName()); try { copyFile(new FileInputStream(file), new FileOutputStream(destination)); } catch (FileNotFoundException e) { Log.e(Constants.TAG, "Error copying file to backup", e); destination = null; } return destination; } public static File getCacheDir(Context mContext) { File dir = mContext.getExternalCacheDir(); if (!dir.exists()) dir.mkdirs(); return dir; } public static File getExternalStoragePublicDir() { File dir = new File( Environment.getExternalStorageDirectory() + File.separator + Constants.TAG + File.separator); if (!dir.exists()) dir.mkdirs(); return dir; } public static File getBackupDir(String backupName) { File backupDir = new File(getExternalStoragePublicDir(), backupName); if (!backupDir.exists()) backupDir.mkdirs(); return backupDir; } public static File getSharedPreferencesFile(Context mContext) { File appData = mContext.getFilesDir().getParentFile(); String packageName = mContext.getApplicationContext().getPackageName(); return new File(appData + System.getProperty("file.separator") + "shared_prefs" + System.getProperty("file.separator") + packageName + "_preferences.xml"); } /** * Returns a directory size in bytes */ @SuppressWarnings("deprecation") public static long getSize(File directory) { StatFs statFs = new StatFs(directory.getAbsolutePath()); long blockSize = 0; try { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR2) { blockSize = statFs.getBlockSizeLong(); } else { blockSize = statFs.getBlockSize(); } // Can't understand why on some devices this fails } catch (NoSuchMethodError e) { Log.e(Constants.TAG, "Mysterious error", e); } return getSize(directory, blockSize); } private static long getSize(File directory, long blockSize) { File[] files = directory.listFiles(); if (files != null) { // space used by directory itself long size = directory.length(); for (File file : files) { if (file.isDirectory()) { // space used by subdirectory size += getSize(file, blockSize); } else { // file size need to rounded up to full block sizes // (not a perfect function, it adds additional block to 0 sized files // and file who perfectly fill their blocks) size += (file.length() / blockSize + 1) * blockSize; } } return size; } else { return 0; } } public static boolean copyDirectory(File sourceLocation, File targetLocation) { boolean res = true; // If target is a directory the method will be iterated if (sourceLocation.isDirectory()) { if (!targetLocation.exists()) { targetLocation.mkdirs(); } String[] children = sourceLocation.list(); for (int i = 0; i < sourceLocation.listFiles().length; i++) { res = res && copyDirectory(new File(sourceLocation, children[i]), new File(targetLocation, children[i])); } // Otherwise a file copy will be performed } else { try { res = res && copyFile(new FileInputStream(sourceLocation), new FileOutputStream(targetLocation)); } catch (FileNotFoundException e) { Log.e(Constants.TAG, "Error copying directory"); res = false; } } return res; } /** * Retrieves uri mime-type using ContentResolver * * @param mContext * @param uri * @return */ public static String getMimeType(Context mContext, Uri uri) { ContentResolver cR = mContext.getContentResolver(); String mimeType = cR.getType(uri); if (mimeType == null) { mimeType = getMimeType(uri.toString()); } return mimeType; } public static String getMimeType(String url) { String type = null; String extension = MimeTypeMap.getFileExtensionFromUrl(url); if (extension != null) { MimeTypeMap mime = MimeTypeMap.getSingleton(); type = mime.getMimeTypeFromExtension(extension); } return type; } /** * Retrieves uri mime-type between the ones managed by application * * @param mContext * @param uri * @return */ public static String getMimeTypeInternal(Context mContext, Uri uri) { String mimeType = getMimeType(mContext, uri); mimeType = getMimeTypeInternal(mContext, mimeType); return mimeType; } /** * Retrieves mime-type between the ones managed by application from given string * * @param mContext * @param mimeType * @return */ public static String getMimeTypeInternal(Context mContext, String mimeType) { if (mimeType != null) { if (mimeType.contains("image/")) { mimeType = Constants.MIME_TYPE_IMAGE; } else if (mimeType.contains("audio/")) { mimeType = Constants.MIME_TYPE_AUDIO; } else if (mimeType.contains("video/")) { mimeType = Constants.MIME_TYPE_VIDEO; } else { mimeType = Constants.MIME_TYPE_FILES; } } return mimeType; } /** * Creates a new attachment file copying data from source file * * @param mContext * @param uri * @return */ public static Attachment createAttachmentFromUri(Context mContext, Uri uri) { return createAttachmentFromUri(mContext, uri, false); } /** * Creates a fiile to be used as attachment. */ public static Attachment createAttachmentFromUri(Context mContext, Uri uri, boolean moveSource) { String name = FileHelper.getNameFromUri(mContext, uri); String extension = FileHelper.getFileExtension(FileHelper.getNameFromUri(mContext, uri)) .toLowerCase(Locale.getDefault()); File f; if (moveSource) { f = createNewAttachmentFile(mContext, extension); try { FileUtils.moveFile(new File(uri.getPath()), f); } catch (IOException e) { Log.e(Constants.TAG, "Can't move file " + uri.getPath()); } } else { f = StorageHelper.createExternalStoragePrivateFile(mContext, uri, extension); } Attachment mAttachment = null; if (f != null) { mAttachment = new Attachment(Uri.fromFile(f), StorageHelper.getMimeTypeInternal(mContext, uri)); mAttachment.setName(name); mAttachment.setSize(f.length()); } return mAttachment; } /** * Creates new attachment from web content * * @param mContext * @param url * @return * @throws IOException */ public static File createNewAttachmentFileFromHttp(Context mContext, String url) throws IOException { if (TextUtils.isEmpty(url)) { return null; } return getFromHttp(url, createNewAttachmentFile(mContext, FileHelper.getFileExtension(url))); } /** * Retrieves a file from its web url * * @param url * @return * @throws IOException */ public static File getFromHttp(String url, File file) throws IOException { URL imageUrl = new URL(url); // HttpURLConnection conn = (HttpURLConnection)imageUrl.openConnection(); // conn.setConnectTimeout(30000); // conn.setReadTimeout(30000); // conn.setInstanceFollowRedirects(true); // InputStream is=conn.getInputStream(); // OutputStream os = new FileOutputStream(f); // Utils.CopyStream(is, os); // File file = File.createTempFile("img", ".jpg"); FileUtils.copyURLToFile(imageUrl, file); // os.close(); return file; } }