Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package com.doplgangr.secrecy.FileSystem; /** * This is an alias of a FILE in the secrecy system. * */ import android.graphics.Bitmap; import com.doplgangr.secrecy.Config; import com.doplgangr.secrecy.Util; import org.apache.commons.io.FilenameUtils; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.Serializable; import java.nio.ByteBuffer; import java.nio.channels.Channels; import java.nio.channels.FileChannel; import java.nio.channels.ReadableByteChannel; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import javax.crypto.CipherInputStream; public class File implements Serializable { public static final String NAME = "FILENAME"; public static final String TYPE = "FILETYPE"; public static final String FILETIMESTAMP = "FILETIMESTAMP"; public static final String FILESIZE = "FILESIZE"; public Boolean decrypting = false; private String name; private String size; private Date Timestamp; private String FileType; private java.io.File file; private java.io.File thumbnailRealFile; private Bitmap thumb = null; private Boolean invalidFile = false; private String key; public File(java.io.File file, String secret) { if (file.exists()) { name = FilenameUtils.getBaseName(file.getName()); try { name = Base64Coder.decodeString(name); //if name is invalid, return original name } catch (IllegalArgumentException ignored) { } FileType = FilenameUtils.getExtension(file.getName()); this.file = file; this.key = secret; String path = file.getParent(); this.size = humanReadableByteCount(file.length()); thumbnailRealFile = new java.io.File(path + "/_thumb" + file.getName()); Timestamp = new Date(file.lastModified()); } else { invalidFile = true; } } private static String humanReadableByteCount(long bytes) { int unit = 1024; if (bytes < unit) return bytes + " B"; int exp = (int) (Math.log(bytes) / Math.log(unit)); char pre = ("KMGTPE").charAt(exp - 1); return String.format("%.1f %sB", bytes / Math.pow(unit, exp), pre); } public String getName() { return name; } public String getSize() { return size; } public Bitmap getThumb(int size) { File thumbnailFile = new File(thumbnailRealFile, key); if ((!thumbnailFile.invalidFile) && (thumb == null)) { CipherInputStream streamThumb = thumbnailFile.readStream(new CryptStateListener() { @Override public void updateProgress(int progress) { } @Override public void setMax(int max) { } @Override public void onFailed(int statCode) { } @Override public void Finished() { } }); this.thumb = storage.getThumbnailfromStream(streamThumb, size); } return thumb; } public boolean hasThumbnail() { File thumbnailFile = new File(thumbnailRealFile, key); return (!thumbnailFile.invalidFile); } public String getType() { return FileType; } public java.io.File getFile() { return file; } public String getTimestamp() { DateFormat df = new SimpleDateFormat("MM/dd/yyyy HH:mm:ss"); if (Timestamp == null) return ""; return df.format(Timestamp); } public java.io.File readFile(CryptStateListener listener) { decrypting = true; InputStream is = null; OutputStream out = null; java.io.File outputFile = null; try { outputFile = java.io.File.createTempFile("tmp" + name, "." + FileType, storage.getTempFolder()); outputFile.mkdirs(); outputFile.createNewFile(); AES_Encryptor enc = new AES_Encryptor(key); is = new CipherInputStream(new FileInputStream(file), enc.decryptstream()); listener.setMax((int) file.length()); ReadableByteChannel inChannel = Channels.newChannel(is); FileChannel outChannel = new FileOutputStream(outputFile).getChannel(); ByteBuffer byteBuffer = ByteBuffer.allocate(Config.bufferSize); while (inChannel.read(byteBuffer) >= 0 || byteBuffer.position() > 0) { byteBuffer.flip(); outChannel.write(byteBuffer); byteBuffer.compact(); listener.updateProgress((int) outChannel.size()); } inChannel.close(); outChannel.close(); Util.log(outputFile.getName(), outputFile.length()); return outputFile; } catch (FileNotFoundException e) { listener.onFailed(2); Util.log("Encrypted File is missing", e.getMessage()); } catch (IOException e) { Util.log("IO Exception while decrypting", e.getMessage()); if (e.getMessage().contains("pad block corrupted")) listener.onFailed(1); else e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); } finally { listener.Finished(); decrypting = false; try { if (is != null) { is.close(); } if (out != null) { out.close(); } } catch (IOException e) { e.printStackTrace(); } } // An error occured. Too Bad if (outputFile != null) storage.purgeFile(outputFile); return null; } public CipherInputStream readStream(CryptStateListener listener) { try { AES_Encryptor enc = new AES_Encryptor(key); return new CipherInputStream(new FileInputStream(file), enc.decryptstream()) { @Override public int available() throws IOException { // The cipher input stream always returns 0 because // in certain implementations (padded ciphers), a // standard implementation may not be able to // accurately determine the number of available // bytes. In our case, however, we are not using a // padded cipher and the number of available bytes // 'should' be the same as the number available from // the underlying stream. int available = in.available(); Util.log("**CipherInputStream.available: " + available); return available; } }; } catch (FileNotFoundException e) { listener.onFailed(2); } catch (Exception e) { e.printStackTrace(); } return null; } public void delete() { storage.purgeFile(file); File thumbnailFile = new File(thumbnailRealFile, key); if (!thumbnailFile.invalidFile) thumbnailFile.delete(); } }