Java Utililty Methods File Read via ByteBuffer

List of utility methods to do File Read via ByteBuffer

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Description

The list of methods to do File Read via ByteBuffer are organized into topic(s).

Method

longreadUint32(final DataInput di)
Read a 32-bit big-endian unsigned integer using a DataInput. 
final byte[] buf8 = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
di.readFully(buf8, 4, 4);
return ByteBuffer.wrap(buf8).getLong();
intreadUint32AsInt(DataInput di)
Overflow checking since java can't handle unsigned numbers. 
final long l = readUint32(di);
if (l > Integer.MAX_VALUE) {
    throw new IOException("uint32 value read overflows int");
return (int) l;
longreadUintLE(byte[] bytes, int pointer, int size)
read Uint LE 
ByteBuffer buffer = ByteBuffer.allocate(8);
buffer.put(bytes, pointer, size);
buffer.put(new byte[8 - size]);
buffer.flip();
return buffer.order(ByteOrder.LITTLE_ENDIAN).getLong();
longreadUnsignedInt(InputStream is)
Reads an unsigned integer (32 bit) from specified input stream. 
return (long) readInt(is) & 0xffffffffL;
intreadUnsignedInt24(InputStream is)
Reads an unsigned 24 bit integer from specified input stream. 
ByteBuffer bb4 = getByteBuffer(4);
for (int cnt = 0; cnt < 3;) {
    int n = is.read(bb4.array(), cnt, bb4.array().length - cnt - 1);
    if (n < 0) {
        throw new IOException("End of stream");
    cnt += n;
bb4.position(0);
return bb4.getInt() & 0xffffff;
StringreadUtf8(DataInput in)
Safely reads a string as UTF-8 from a byte stream. 
byte[] bytes = new byte[in.readInt()];
in.readFully(bytes);
return decodeUtf8(bytes);
longreadVarLong(byte[] arr)
read Var Long 
return readVarLong(ByteBuffer.wrap(arr));
short[]readWaveFile44100_16Bit_Mono(String dir, String name)
read Wave Fil Bi Mono 
try {
    return readWaveFile44100_16Bit_Mono(new BufferedInputStream(new FileInputStream(new File(dir, name))));
} catch (FileNotFoundException e) {
    e.printStackTrace();
    return null;
booleanreadWavHeader(DataInputStream inStrm, FileChannel fc)
read Wav Header 
byte[] buf = new byte[16];
int size;
ByteBuffer bb = ByteBuffer.wrap(buf).order(ByteOrder.LITTLE_ENDIAN);
bb.clear();
try {
    inStrm.readInt();
    inStrm.readFully(buf, 0, 8);
    if (!"WAVEfmt ".equals(new String(buf, 0, 8)))
...
voidreadWholeFile(File file, StringBuilder stringBuilder)
Reads a whole file into a StringBuffer based on java.nio 
long length = file.length();
MappedByteBuffer in = new FileInputStream(file).getChannel().map(FileChannel.MapMode.READ_ONLY, 0, length);
int i = 0;
while (i < length)
    stringBuilder.append((char) in.get(i++));