Example usage for com.google.common.io ByteStreams newDataInput

Introduction

In this page you can find the example usage for com.google.common.io ByteStreams newDataInput.

Prototype

public static ByteArrayDataInput newDataInput(byte[] bytes, int start) 

Source Link

Document

Returns a new ByteArrayDataInput instance to read from the bytes array, starting at the given position.

Usage

From source file:de.nx42.maps4cim.header.HeaderParser.java

/**
 * Actually parses the relevant part of the header and writes the results
 * into a new CustomHeader-object/*from   w  ww . j  av a 2  s  . c  o m*/
 * @param header a byte-array containing at least the relevant part of the
 * map's header (can be retrieved via {@link HeaderParser#getRelevantPart(InputStream)})
 * @return the CustomHeader-object containing the data of this header
 * @throws ParseException if there is an error parsing the header
 */
protected static CustomHeader execute(byte[] header) throws ParseException {
    CustomHeader ch = CustomHeader.newEmpty();

    // read intro
    int introEnd = readToString(header, 0);
    ch.intro = Arrays.copyOfRange(header, 0, introEnd);

    // read date/times
    int dateStart = readAfterGap(header, introEnd, 3);
    int dateEnd = readAfterBytes(header, dateStart, CustomHeader.staticBinary01)
            - CustomHeader.staticBinary01.length;

    // read 64 bit integers (date/time) until end is reached
    int dateAmount = (dateEnd - dateStart) / 8;
    long[] dateTimeStamps = new long[dateAmount];
    ByteArrayDataInput bin = ByteStreams.newDataInput(header, dateStart);

    for (int i = 0; i < dateAmount; i++) {
        dateTimeStamps[i] = bin.readLong();
    }

    // interpret dates
    if (dateAmount >= 6) {
        // current format (custom map)
        ch.unusedDate1 = DateUtils.ticksToDate(dateTimeStamps[0]);
        ch.unusedDate2 = DateUtils.ticksToDate(dateTimeStamps[1]);
        ch.lastSaved = DateUtils.ticksToDate(dateTimeStamps[2]);
        ch.mapCreated = DateUtils.ticksToDate(dateTimeStamps[3]);
        ch.workTime1 = dateTimeStamps[4];
        ch.workTime2 = dateTimeStamps[5];
    } else if (dateAmount >= 4) {
        // old format (campaign map), without mapCreated and workTime2
        ch.unusedDate1 = DateUtils.ticksToDate(dateTimeStamps[0]);
        ch.unusedDate2 = DateUtils.ticksToDate(dateTimeStamps[1]);
        ch.lastSaved = ch.mapCreated = DateUtils.ticksToDate(dateTimeStamps[2]);
        ch.workTime1 = ch.workTime2 = dateTimeStamps[3];
    } else {
        // fail, just write some default values
        log.warn("Can't read date & time values: unexpected format");
        ch.unusedDate1 = ch.unusedDate2 = CustomHeader.unusedDateDefault;
        ch.lastSaved = ch.mapCreated = DateUtils.getDateUTC(2013, 1, 1, 12, 0, 0);
    }

    // read map name
    int nameStart = readAfterString(header, dateEnd, CustomHeader.staticString02);
    ch.mapName = parseHeaderString(header, nameStart);

    // get minimap PNG length (watch out for euro update strings!)
    int mapNameEnd = readAfterString(header, nameStart);
    int beginPngLen = mapNameEnd;
    int firstStringAfterMapName = readToString(header, mapNameEnd);
    if (mapNameEnd == firstStringAfterMapName) {
        beginPngLen = readAfterString(header, firstStringAfterMapName);
    }

    // read minimap image
    ch.pngLength = Arrays.copyOfRange(header, beginPngLen, beginPngLen + 3);
    int beginPng = beginPngLen + 3;
    int pngLength = int24parse(ch.pngLength);
    int pngEnd = beginPng + pngLength;
    ch.png = Arrays.copyOfRange(header, beginPng, pngEnd);

    // find out if euro building style
    int firstStringAfterPng = readToString(header, pngEnd);

    String europeIdentifier = parseHeaderString(header, firstStringAfterPng);
    ch.buildingSet = europeIdentifier.contains("cim2.europe") ? BuildingSet.EUROPEAN : BuildingSet.AMERICAN;

    return ch;
}

---