| /* |
| * 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.afp.modca; |
| |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| import org.apache.commons.io.output.ByteArrayOutputStream; |
| |
| import org.apache.fop.afp.ptoca.PtocaConstants; |
| import org.apache.fop.afp.util.BinaryUtils; |
| |
| /** |
| * Presentation text data contains the graphic characters and the control |
| * sequences necessary to position the characters within the object space. The |
| * data consists of: - graphic characters to be presented - control sequences |
| * that position them - modal control sequences that adjust the positions by |
| * small amounts - other functions causing text to be presented with differences |
| * in appearance. |
| * <p> |
| * The graphic characters are expected to conform to a coded font representation |
| * so that they can be translated from the code point in the object data to the |
| * character in the coded font. The units of measure for linear displacements |
| * are derived from the PresentationTextDescriptor or from the hierarchical |
| * defaults. |
| * <p> |
| * In addition to graphic character code points, Presentation Text data can |
| * contain embedded control sequences. These are strings of two or more bytes |
| * which signal an alternate mode of processing for the content of the current |
| * Presentation Text data. |
| * <p> |
| * The content for this object can be created using {@link org.apache.fop.afp.ptoca.PtocaBuilder}. |
| */ |
| public class PresentationTextData extends AbstractAFPObject implements PtocaConstants { |
| |
| /** the maximum size of the presentation text data.*/ |
| private static final int MAX_SIZE = 8192; |
| |
| /** the AFP data relating to this presentation text data. */ |
| private final ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| |
| /** |
| * Default constructor for the PresentationTextData. |
| */ |
| public PresentationTextData() { |
| this(false); |
| } |
| |
| private static final int HEADER_LENGTH = 9; |
| |
| /** |
| * Constructor for the PresentationTextData, the boolean flag indicate |
| * whether the control sequence prefix should be set to indicate the start |
| * of a new control sequence. |
| * |
| * @param controlInd |
| * The control sequence indicator. |
| */ |
| public PresentationTextData(boolean controlInd) { |
| final byte[] data = { |
| 0x5A, // Structured field identifier |
| 0x00, // Record length byte 1 |
| 0x00, // Record length byte 2 |
| SF_CLASS, // PresentationTextData identifier byte 1 |
| Type.DATA, // PresentationTextData identifier byte 2 |
| Category.PRESENTATION_TEXT, // PresentationTextData identifier byte 3 |
| 0x00, // Flag |
| 0x00, // Reserved |
| 0x00, // Reserved |
| }; |
| baos.write(data, 0, HEADER_LENGTH); |
| |
| if (controlInd) { |
| baos.write(new byte[] {0x2B, (byte) 0xD3}, 0, 2); |
| } |
| } |
| |
| /** |
| * Returns the number of data bytes still available in this object until it is full and a new |
| * one has to be started. |
| * @return the number of data bytes available |
| */ |
| public int getBytesAvailable() { |
| return MAX_SIZE - baos.size() + HEADER_LENGTH; |
| } |
| |
| /** |
| * Returns the output stream the content data is written to. |
| * @return the output stream |
| */ |
| protected OutputStream getOutputStream() { |
| return this.baos; |
| } |
| |
| /** {@inheritDoc} */ |
| public void writeToStream(OutputStream os) throws IOException { |
| assert getBytesAvailable() >= 0; |
| byte[] data = baos.toByteArray(); |
| byte[] size = BinaryUtils.convert(data.length - 1, 2); |
| data[1] = size[0]; |
| data[2] = size[1]; |
| os.write(data); |
| } |
| |
| } |