+ * Please use {@link Image#Image(InputStream)} when possible instead, with a + * {@link Base64InputStream}; it can be much more efficient. + * + * @param base64EncodedData + * the Base64 encoded data as a String + * + * @throws IOException + * in case of I/O error or badly formated Base64 + */ + public Image(String base64EncodedData) throws IOException { + this(new Base64InputStream(new ByteArrayInputStream( + StringUtils.getBytes(base64EncodedData)), false)); + } + + /** + * Create a new {@link Image} from a stream. + * + * @param in + * the stream + * + * @throws IOException + * in case of I/O error + */ + public Image(InputStream in) throws IOException { + data = getTemporaryFile(); + size = IOUtils.write(in, data); + } + + /** + * The size of the enclosed image in bytes. + * + * @return the size + */ + public long getSize() { + return size; + } + + /** + * Generate an {@link InputStream} that you can {@link InputStream#reset()} + * for this {@link Image}. + *
+ * This {@link InputStream} will (always) be a new one, and you are + * responsible for it. + *
+ * Note: take care that the {@link InputStream} must not live past + * the {@link Image} life time! + * + * @return the stream + * + * @throws IOException + * in case of I/O error + */ + public InputStream newInputStream() throws IOException { + return new MarkableFileInputStream(data); + } + + /** + * Read the actual image data, as a byte array. + * + * @deprecated if possible, prefer the {@link Image#newInputStream()} + * method, as it can be more efficient + * + * @return the image data + */ + @Deprecated + public byte[] getData() { + try { + InputStream in = newInputStream(); + try { + return IOUtils.toByteArray(in); + } finally { + in.close(); + } + } catch (IOException e) { + throw new RuntimeException(e); + } + } + + /** + * Convert the given {@link Image} object into a Base64 representation of + * the same {@link Image} object. + * + * @deprecated Please use {@link Image#newInputStream()} instead, it is more + * efficient + * + * @return the Base64 representation + */ + @Deprecated + public String toBase64() { + try { + Base64InputStream stream = new Base64InputStream(newInputStream(), + true); + try { + return IOUtils.readSmallStream(stream); + } finally { + stream.close(); + } + } catch (IOException e) { + return null; + } + } + + /** + * Closing the {@link Image} will delete the associated temporary file on + * disk. + *
+ * Note that even if you don't, the program will still try to delete + * all the temporary files at JVM termination. + */ + @Override + public void close() throws IOException { + synchronized (instanceLock) { + if (size >= 0) { + size = -1; + data.delete(); + data = null; + + synchronized (lock) { + count--; + if (count <= 0) { + count = 0; + tmpRepository.close(); + tmpRepository = null; + } + } + } + } + } + + @Override + protected void finalize() throws Throwable { + try { + close(); + } finally { + super.finalize(); + } + } + + /** + * Return a newly created temporary file to work on. + * + * @return the file + * + * @throws IOException + * in case of I/O error + */ + private File getTemporaryFile() throws IOException { + synchronized (lock) { + if (tmpRepository == null) { + tmpRepository = new TempFiles(tempRoot, "images"); + count = 0; + } + + count++; + + return tmpRepository.createTempFile("image"); + } + } + + /** + * Write this {@link Image} for serialization purposes; that is, write the + * content of the backing temporary file. + * + * @param out + * the {@link OutputStream} to write to + * + * @throws IOException + * in case of I/O error + */ + private void writeObject(ObjectOutputStream out) throws IOException { + InputStream in = newInputStream(); + try { + IOUtils.write(in, out); + } finally { + in.close(); + } + } + + /** + * Read an {@link Image} written by + * {@link Image#writeObject(java.io.ObjectOutputStream)}; that is, create a + * new temporary file with the saved content. + * + * @param in + * the {@link InputStream} to read from + * @throws IOException + * in case of I/O error + * @throws ClassNotFoundException + * will not be thrown by this method + */ + @SuppressWarnings("unused") + private void readObject(ObjectInputStream in) throws IOException, + ClassNotFoundException { + data = getTemporaryFile(); + IOUtils.write(in, data); + } + + /** + * Change the temporary root directory used by the program. + *
+ * Caution: the directory will be owned by the system, all its files + * now belong to us (and will most probably be deleted). + *
+ * Note: it may take some time until the new temporary root is used, we + * first need to make sure the previous one is not used anymore (i.e., we + * must reach a point where no unclosed {@link Image} remains in memory) to + * switch the temporary root. + * + * @param root + * the new temporary root, which will be owned by the + * system + */ + public static void setTemporaryFilesRoot(File root) { + tempRoot = root; + } +}