- /*
- * 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.
- */
-
- /* $Id$ */
-
- package org.apache.fop.pdf;
-
- import java.io.ByteArrayOutputStream;
- import java.io.IOException;
- import java.io.OutputStream;
- import java.io.OutputStreamWriter;
- import java.io.Writer;
- import java.security.MessageDigest;
- import java.security.NoSuchAlgorithmException;
-
- /**
- * Class representing a PDF stream.
- * <p>
- * A derivative of the PDF Object, a PDF Stream has not only a dictionary
- * but a stream of PDF commands. The stream of commands is where the real
- * work is done, the dictionary just provides information like the stream
- * length.
- */
- public class PDFStream extends AbstractPDFStream {
-
- /**
- * The stream of PDF commands
- */
- protected StreamCache data;
-
- private transient Writer streamWriter;
- private transient char[] charBuffer;
-
- /**
- * Create an empty stream object
- */
- public PDFStream() {
- setUp();
- }
-
- public PDFStream(PDFDictionary dictionary) {
- super(dictionary);
- setUp();
- }
-
- public PDFStream(PDFDictionary dictionary, boolean encodeOnTheFly) {
- super(dictionary, encodeOnTheFly);
- setUp();
- }
-
- public PDFStream(boolean encodeOnTheFly) {
- super(encodeOnTheFly);
- setUp();
- }
-
- private void setUp() {
- try {
- data = StreamCacheFactory.getInstance().createStreamCache();
- this.streamWriter = new OutputStreamWriter(
- getBufferOutputStream(), PDFDocument.ENCODING);
- //Buffer to minimize calls to the converter
- this.streamWriter = new java.io.BufferedWriter(this.streamWriter);
- } catch (IOException e) {
- throw new RuntimeException(e);
- }
- }
-
- /**
- * Append data to the stream
- *
- * @param s the string of PDF to add
- */
- public void add(String s) {
- try {
- this.streamWriter.write(s);
- } catch (IOException ex) {
- //TODO throw the exception and catch it elsewhere
- ex.printStackTrace();
- }
- }
-
- /**
- * Append data to the stream
- *
- * @param sb the string buffer of PDF to add
- */
- public void add(StringBuffer sb) {
- try {
- int nHave = sb.length();
- if (charBuffer == null) {
- charBuffer = new char [ nHave * 2 ];
- } else {
- int nAvail = charBuffer.length;
- if (nAvail < nHave) {
- int nAlloc = nAvail;
- while (nAlloc < nHave) {
- nAlloc *= 2;
- }
- charBuffer = new char [ nAlloc ];
- }
- }
- sb.getChars(0, nHave, charBuffer, 0);
- this.streamWriter.write(charBuffer, 0, nHave);
- } catch (IOException ex) {
- //TODO throw the exception and catch it elsewhere
- ex.printStackTrace();
- }
- }
-
- private void flush() throws IOException {
- this.streamWriter.flush();
- }
-
- /**
- * Returns a Writer that writes to the OutputStream of the buffer.
- * @return the Writer
- */
- public Writer getBufferWriter() {
- return this.streamWriter;
- }
-
- /**
- * Returns an OutputStream that can be used to write to the buffer which is used
- * to build up the PDF stream.
- * @return the OutputStream
- * @throws IOException In case of an I/O problem
- */
- public OutputStream getBufferOutputStream() throws IOException {
- if (this.streamWriter != null) {
- flush(); //Just to be sure
- }
- return this.data.getOutputStream();
- }
-
- /**
- * Used to set the contents of the PDF stream.
- * @param data the contents as a byte array
- * @throws IOException in case of an I/O problem
- */
- public void setData(byte[] data) throws IOException {
- this.data.clear();
- this.data.write(data);
- }
-
- /**
- * Returns the size of the content.
- * @return size of the content
- */
- public int getDataLength() {
- try {
- flush();
- return data.getSize();
- } catch (Exception e) {
- //TODO throw the exception and catch it elsewhere
- e.printStackTrace();
- return 0;
- }
- }
-
- /** {@inheritDoc} */
- protected int getSizeHint() throws IOException {
- flush();
- return data.getSize();
- }
-
- /** {@inheritDoc} */
- protected void outputRawStreamData(OutputStream out) throws IOException {
- flush();
- data.outputContents(out);
- }
-
- /**
- * {@inheritDoc}
- */
- public int output(OutputStream stream) throws IOException {
- final int len = super.output(stream);
-
- //Now that the data has been written, it can be discarded.
- // this.data = null;
- return len;
- }
-
- public String streamHashCode() throws IOException {
- ByteArrayOutputStream bos = new ByteArrayOutputStream();
- outputRawStreamData(bos);
- try {
- MessageDigest md = MessageDigest.getInstance("MD5");
- byte[] thedigest = md.digest(bos.toByteArray());
- StringBuilder hex = new StringBuilder();
- for (byte b : thedigest) {
- hex.append(String.format("%02x", b));
- }
- return hex.toString();
- } catch (NoSuchAlgorithmException e) {
- throw new IOException(e);
- }
- }
- }
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