/*
* $Id: Abbreviations.java 536 2008-02-19 06:03:27Z weiju $
*
* Created on 2005/09/25
* Copyright 2005-2008 by Wei-ju Wu
* This file is part of The Z-machine Preservation Project (ZMPP).
*
* ZMPP is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* ZMPP is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with ZMPP. If not, see <http://www.gnu.org/licenses/>.
*/
package org.zmpp.vm;
import org.zmpp.base.Memory;
import org.zmpp.encoding.ZCharDecoder.AbbreviationsTable;
/**
* This class represents a view to the abbreviations table. The table starts at
* the predefined address within the header and contains pointers to ZSCII
* strings in the memory map. These pointers are word addresses as opposed to
* all other addresses in the memory map, therefore the actual value has to
* multiplied by two to get the real address.
*
* @author Wei-ju Wu
* @version 1.0
*/
public class Abbreviations implements AbbreviationsTable {
/**
* The memory object.
*/
private Memory memory;
/**
* The start address of the abbreviations table.
*/
private int address;
/**
* Constructor.
*
* @param memory the memory map
* @param address the start address of the abbreviations table
*/
public Abbreviations(final Memory memory, final int address) {
super();
this.memory = memory;
this.address = address;
}
/**
* The abbreviation table contains word addresses, so read out the pointer
* and multiply by two
*
* @param entryNum the entry index in the abbreviations table
* @return the word address
*/
public int getWordAddress(final int entryNum) {
return memory.readUnsignedShort(address + entryNum * 2) * 2;
}
}