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The Adobe Experience Manager SDK
There is a newer version: 2025.3.19823.20250304T101418Z-250200
/*
*
*	File: Index.java
*
*
*	ADOBE CONFIDENTIAL
*	___________________
*
*	Copyright 2004 Adobe Systems Incorporated
*	All Rights Reserved.
*
*	NOTICE: All information contained herein is, and remains the property of
*	Adobe Systems Incorporated and its suppliers, if any. The intellectual
*	and technical concepts contained herein are proprietary to Adobe Systems
*	Incorporated and its suppliers and may be covered by U.S. and Foreign
*	Patents, patents in process, and are protected by trade secret or
*	copyright law. Dissemination of this information or reproduction of this
*	material is strictly forbidden unless prior written permission is obtained
*	from Adobe Systems Incorporated.
*
*/

package com.adobe.fontengine.font.cff;

import com.adobe.fontengine.font.InvalidFontException;
import com.adobe.fontengine.font.UnsupportedFontException;
import com.adobe.fontengine.font.cff.CFFByteArray.CFFByteArrayBuilder;

/** Represents an INDEX structure.
 */
class Index {
  
  /* Our strategy is to entirely parse an Index at construction time. We 
   * still need to retain some access to the bits to deliver them (this 
   * is particularly true for superclasses of this one, such as NameIndex). */
  
  /** The container for our bytes. */
  public final CFFByteArray data;
  /** The offset of our bytes in data. */
  public final int offset;
  
  /** The size of the INDEX structure, in bytes. */
  protected final int size;
  
  /** The number of entries in the index. */
  protected final int entryCount;
  
  /** The offsets of the entries, relative to the beginning of the 
   * data array. If there are no entries, entryOffsets
   * is undefined. Otherwise, this array has entryCount + 1
   * elements, with the last entry being the offset of the byte following
   * the last byte of the last entry.
   */
  protected final int[] entryOffsets;
  
  
  /** Construct a Index from a CFFByteArray.
   * @param data the CFFByteArray to get data from
   * @param offset the offset of the first byte in data
   */
  Index (CFFByteArray data, int offset)
      throws InvalidFontException, UnsupportedFontException {
    
    this.data = data;
    this.offset = offset;
    
    entryCount = data.getcard16 (offset + 0);
    entryOffsets = new int [entryCount + 1];
    
    if (entryCount == 0) {
      size = 2;
      return; }
    
    int offSize = data.getOffSize (offset + 2);
    int firstDataByteOffset = offset + 3 + offSize * (entryCount + 1);
    for (int i = 0; i < entryCount + 1; i++) {
      entryOffsets [i] = firstDataByteOffset
                           + data.getOffset (offset + 3 + offSize * i, offSize,
                               "INDEX offset too big")
                           - 1; }
    
    size = entryOffsets [entryCount] - offset;
  }
  
  /** The size, in bytes, of this INDEX in the data.*/
  public int size () {
    return size;
  }
  
  /** The number of entries in the INDEX.
   */
  public int getCount () {
    return entryCount;
  }
  
  /** The offset, in data, of entry.
   */
  public int offsetOf (int entry) {
    return entryOffsets [entry];
  }
  
  /** The offset, in data, of the first byte following entry.
   */
  public int offsetFollowing (int entry) {
    return entryOffsets [entry + 1];
  }

  /** The size, in bytes, of entry.
   */
  public int sizeOf (int entry) {
    return entryOffsets [entry + 1] - entryOffsets [entry];
  }
  
  
  public void stream (CFFByteArrayBuilder bb) throws InvalidFontException {
    bb.addBytes (data, offset, size);
  }
  
  static public class Cursor {
    int base;
    int offset; }
  
  static public Cursor startIndex (CFFByteArrayBuilder bb, int n) {
    if (n == 0) {
      bb.addCard16 (0);
      return null; }

    bb.addCard16 (n);
    bb.addCard8 (4);

    bb.addCard32 (1);

    Cursor cursor = new Cursor ();
    cursor.offset = bb.getSize();

    for (int i = 0; i < n; i++) {
      bb.addCard32 (1); }

    cursor.base = bb.getSize() - 1; 
    return cursor;
  }

  static public Cursor elementEntered (CFFByteArrayBuilder bb, Cursor cursor) {
    bb.setCard32 (cursor.offset, bb.getSize() - cursor.base);
    cursor.offset += 4;
    return cursor;
  }
}