// **********************************************************************// // <copyright>// //  BBN Technologies//  10 Moulton Street//  Cambridge, MA 02138//  (617) 873-8000// //  Copyright (C) BBNT Solutions LLC. All rights reserved.// // </copyright>// **********************************************************************// // $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/layer/vpf/DcwVariableLengthIndexFile.java,v $// $RCSfile: DcwVariableLengthIndexFile.java,v $// $Revision: 1.2.2.2 $// $Date: 2005/08/09 21:17:51 $// $Author: dietrick $// // **********************************************************************package com.bbn.openmap.layer.vpf;import java.io.IOException;import com.bbn.openmap.io.FormatException;import com.bbn.openmap.io.BinaryFile;import com.bbn.openmap.io.BinaryBufferedFile;/** * Read in a VPF variable length index file, and allows access to * individual records. */public class DcwVariableLengthIndexFile {    /** holds all the offset,size pairs */    final private int offsettable[];    /** the number of records */    final private int recordCount;    /** the end of the file offset */    final private int endOfFileOffset;    /**     * Construct a new index file.     *      * @param filename the name of the file to read in.     * @param msbfirst the byte order of the file to be read.     * @exception FormatException some error was encountered in trying     *            to read the file.     */    public DcwVariableLengthIndexFile(String filename, boolean msbfirst)            throws FormatException, IOException {        this(new BinaryBufferedFile(filename), msbfirst);    }    /**     * Construct a new index file.     *      * @param inputstream BinaryBufferedFile handle.     * @param msbfirst the byte order of the file to be read.     * @exception FormatException some error was encountered in trying     *            to read the file.     */    public DcwVariableLengthIndexFile(BinaryFile inputstream, boolean msbfirst)            throws FormatException {        try {            inputstream.byteOrder(msbfirst);            recordCount = inputstream.readInteger();            /*int HeaderLength = */inputstream.readInteger();            offsettable = new int[recordCount * 2];            inputstream.readIntegerArray(offsettable, 0, recordCount * 2);            endOfFileOffset = offsettable[offsettable.length - 2]                    + offsettable[offsettable.length - 1];            inputstream.close();            //          com.bbn.openmap.util.Debug.output("VLI.init(): number            // of entries(" + recordCount +            //                                            ") HeaderLength(" + HeaderLength + ")");        } catch (IOException i) {            throw new FormatException("IOException with "                    + inputstream.getName() + ": " + i.getMessage());        }    }    /**     * get the offset byte offset of the record in the associated     * table file. If recordNumber is greater than the number of     * records, this returns the offset of the end-of-file.     *      * @param recordNumber the record to retrieve the offset for     */    public int recordOffset(int recordNumber) {        return (recordCount < recordNumber) ? endOfFileOffset                : offsettable[(recordNumber - 1) * 2];    }    /**     * get the size of the record in the associated table file If     * recordNumber is greater than the number of records, this     * returns a record size of 0.     *      * @param recordNumber the record to retrieve the offset for     */    public int recordSize(int recordNumber) {        return (recordCount < recordNumber) ? 0                : offsettable[(recordNumber - 1) * 2 + 1];    }    /** get the number of records in the index file */    public int getRecordCount() {        return recordCount;    }    /** close the associated input file */    public void close() {}}