Java Code Examples for net.jpountz.lz4.LZ4Factory#fastestInstance()

@Override
public byte[] uncompress(byte[] data) throws IOException {
	LZ4Factory factory = LZ4Factory.fastestInstance();
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	LZ4FastDecompressor decompresser = factory.fastDecompressor();
	LZ4BlockInputStream lzis = new LZ4BlockInputStream(new ByteArrayInputStream(data), decompresser);
	
	int count;
	byte[] buffer = new byte[2048];
	while ((count = lzis.read(buffer)) != -1) {
		baos.write(buffer, 0, count);
	}
	lzis.close();
	
	return baos.toByteArray();
}
 

public static void main(String[] args) throws Exception {

        if(args.length == 0){
            System.out.println("args[0] must be data file path");
            return;
        }
        LZ4Factory factory = LZ4Factory.fastestInstance();

        byte[] data = Files.toByteArray(new File(args[0]));
        final int decompressedLength = data.length;

        // compress data
        LZ4Compressor compressor = factory.fastCompressor();
        long start = System.currentTimeMillis();
        int maxCompressedLength = compressor.maxCompressedLength(decompressedLength);
        byte[] compressed = new byte[maxCompressedLength];
        int compressedLength = compressor.compress(data, 0, decompressedLength, compressed, 0, maxCompressedLength);
        System.out.println("compress take:" + (System.currentTimeMillis() - start));
        System.out.println(compressedLength);

        // decompress data
        // - method 1: when the decompressed length is known
        LZ4FastDecompressor decompressor = factory.fastDecompressor();
        start = System.currentTimeMillis();
        byte[] restored = new byte[decompressedLength];
        int compressedLength2 = decompressor.decompress(compressed, 0, restored, 0, decompressedLength);
        System.out.println("decompress take:" + (System.currentTimeMillis() - start));
        System.out.println(decompressedLength);
        // compressedLength == compressedLength2

        // - method 2: when the compressed length is known (a little slower)
        // the destination buffer needs to be over-sized
        LZ4SafeDecompressor decompressor2 = factory.safeDecompressor();
        int decompressedLength2 = decompressor2.decompress(compressed, 0, compressedLength, restored, 0);
    }
 

private Lz4FrameEncoder newEncoder(int blockSize, int maxEncodeSize) {
    Checksum checksum = XXHashFactory.fastestInstance().newStreamingHash32(DEFAULT_SEED).asChecksum();
    Lz4FrameEncoder encoder = new Lz4FrameEncoder(LZ4Factory.fastestInstance(), true,
                                                  blockSize,
                                                  checksum,
                                                  maxEncodeSize);
    encoder.handlerAdded(ctx);
    return encoder;
}
 

@Override
public byte[] compress(byte[] data) throws IOException {
	LZ4Factory factory = LZ4Factory.fastestInstance();
	ByteArrayOutputStream byteOutput = new ByteArrayOutputStream();
	LZ4Compressor compressor = factory.fastCompressor();
	LZ4BlockOutputStream compressedOutput = new LZ4BlockOutputStream(byteOutput, 2048, compressor);
	compressedOutput.write(data);
	compressedOutput.close();
	
	return byteOutput.toByteArray();
}
 

public static void main(String[] args) throws Exception {

        if(args.length == 0){
            System.out.println("args[0] must be data file path");
            return;
        }
        LZ4Factory factory = LZ4Factory.fastestInstance();

        byte[] data = Files.toByteArray(new File(args[0]));
        final int decompressedLength = data.length;

        // compress data
        LZ4Compressor compressor = factory.fastCompressor();
        long start = System.currentTimeMillis();
        int maxCompressedLength = compressor.maxCompressedLength(decompressedLength);
        byte[] compressed = new byte[maxCompressedLength];
        int compressedLength = compressor.compress(data, 0, decompressedLength, compressed, 0, maxCompressedLength);
        System.out.println("compress take:" + (System.currentTimeMillis() - start));
        System.out.println(compressedLength);

        // decompress data
        // - method 1: when the decompressed length is known
        LZ4FastDecompressor decompressor = factory.fastDecompressor();
        start = System.currentTimeMillis();
        byte[] restored = new byte[decompressedLength];
        int compressedLength2 = decompressor.decompress(compressed, 0, restored, 0, decompressedLength);
        System.out.println("decompress take:" + (System.currentTimeMillis() - start));
        System.out.println(decompressedLength);
        // compressedLength == compressedLength2

        // - method 2: when the compressed length is known (a little slower)
        // the destination buffer needs to be over-sized
        LZ4SafeDecompressor decompressor2 = factory.safeDecompressor();
        int decompressedLength2 = decompressor2.decompress(compressed, 0, compressedLength, restored, 0);
    }
 

public String getDataTypePriv() throws IOException {
	RandomAccessFile fin = new RandomAccessFile(sinfile,"r");
	byte[] res=null;
	byte[] rescomp=null;
	if (dataHeader.mmcfLen>0) {
		Object block = dataBlocks.firstElement();
		if (block instanceof AddrBlock) {
			res = new byte[(int)((AddrBlock)block).dataLen];
			fin.seek(getDataOffset()+((AddrBlock)block).dataOffset);
			fin.read(res);
			fin.close();
		}
		else {
			rescomp = new byte[(int)((LZ4ABlock)block).compDataLen];
			fin.seek(getDataOffset()+((LZ4ABlock)block).dataOffset);
			fin.read(rescomp);
			fin.close();
			LZ4Factory factory = LZ4Factory.fastestInstance();
			LZ4FastDecompressor decomp = factory.fastDecompressor();
			res = decomp.decompress(rescomp, (int)((LZ4ABlock)block).uncompDataLen);
		}
	}
	else {
		res = new byte[blocks.blocks[0].length];
		fin.seek(getDataOffset());
		fin.read(res);
		fin.close();
	}
	return getDataTypePriv(res);
}
 

private void read() throws IOException
{
    this.nso0 = new NSO0Header(this.fileReader, 0x0);
    
    LZ4Factory factory = LZ4Factory.fastestInstance();
    LZ4FastDecompressor decompressor = factory.fastDecompressor();
    
    NSO0SectionHeader textHeader = this.nso0.getSectionHeader(NXOSectionType.TEXT);
    NSO0SectionHeader rodataHeader = this.nso0.getSectionHeader(NXOSectionType.RODATA);
    NSO0SectionHeader dataHeader = this.nso0.getSectionHeader(NXOSectionType.DATA);
    
    int textOffset = textHeader.getMemoryOffset();
    int rodataOffset = rodataHeader.getMemoryOffset();
    int dataOffset = dataHeader.getMemoryOffset();
    int textSize = textHeader.getDecompressedSize();
    int rodataSize = rodataHeader.getDecompressedSize();
    int dataSize = dataHeader.getDecompressedSize();
    
    // The data section is last, so we use its offset + decompressed size
    byte[] full = new byte[dataOffset + dataSize];
    byte[] decompressedText;
    byte[] decompressedRodata;
    byte[] decompressedData;
    
    if (this.nso0.isSectionCompressed(NXOSectionType.TEXT))
    {
        byte[] compressedText = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.TEXT), this.nso0.getCompressedSectionSize(NXOSectionType.TEXT));
        decompressedText = new byte[textSize];
        decompressor.decompress(compressedText, decompressedText);
    }
    else
    {
        decompressedText = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.TEXT), textSize);
    }
    
    System.arraycopy(decompressedText, 0, full, textOffset, textSize);
    
    if (this.nso0.isSectionCompressed(NXOSectionType.RODATA))
    {
        byte[] compressedRodata = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.RODATA), this.nso0.getCompressedSectionSize(NXOSectionType.RODATA));
        decompressedRodata = new byte[rodataSize];
        decompressor.decompress(compressedRodata, decompressedRodata);
    }
    else
    {
        decompressedRodata = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.RODATA), rodataSize);
    }
    
    System.arraycopy(decompressedRodata, 0, full, rodataOffset, rodataSize);
    
    if (this.nso0.isSectionCompressed(NXOSectionType.DATA))
    {
        byte[] compressedData = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.DATA), this.nso0.getCompressedSectionSize(NXOSectionType.DATA));
        decompressedData = new byte[dataSize];
        decompressor.decompress(compressedData, decompressedData);
    }
    else
    {
        decompressedData = this.fileProvider.readBytes(this.nso0.getSectionFileOffset(NXOSectionType.DATA), dataSize);
    }
    
    System.arraycopy(decompressedData, 0, full, dataOffset, dataSize);
    this.memoryProvider = new ByteArrayProvider(full);
    
    this.sections = new NXOSection[3];
    this.sections[NXOSectionType.TEXT.ordinal()] = new NXOSection(NXOSectionType.TEXT, textOffset, textSize);
    this.sections[NXOSectionType.RODATA.ordinal()] = new NXOSection(NXOSectionType.RODATA, rodataOffset, rodataSize);
    this.sections[NXOSectionType.DATA.ordinal()] = new NXOSection(NXOSectionType.DATA, dataOffset, dataSize);
}
 

public ODAGPartLZ4Wrapper() {
    lz4factory = LZ4Factory.fastestInstance();
    reset();
}
 

public ODAGStashLZ4Wrapper() {
    lz4factory = LZ4Factory.fastestInstance();
    reset();
}
 

public LZ4ObjectCache() {
    lz4factory = LZ4Factory.fastestInstance();
    reset();
}
 

public static LZ4Factory fastestInstance() {
	return IBM_FIX ? LZ4Factory.unsafeInstance() : LZ4Factory.fastestInstance();
}
 

private LZ4Compressor()
{
    final LZ4Factory lz4Factory = LZ4Factory.fastestInstance();
    compressor = lz4Factory.fastCompressor();
    decompressor = lz4Factory.decompressor();
}
 

private LZ4Compressor()
{
    final LZ4Factory lz4Factory = LZ4Factory.fastestInstance();
    compressor = lz4Factory.fastCompressor();
    decompressor = lz4Factory.decompressor();
}
 

/**
 * Creates a new LZ4 encoder with hight or fast compression, default block size (64 KB)
 * and xxhash hashing for Java, based on Yann Collet's work available at
 * <a href="https://github.com/Cyan4973/xxHash">Github</a>.
 *
 * @param highCompressor  if {@code true} codec will use compressor which requires more memory
 *                        and is slower but compresses more efficiently
 *                        基于Yann Collet在Github上的工作，为Java创建一个新的LZ4编码器，它具有较高或快速的压缩、默认块大小(64 KB)和xxhash散列。
 */
public Lz4FrameEncoder(boolean highCompressor) {
    this(LZ4Factory.fastestInstance(), highCompressor, DEFAULT_BLOCK_SIZE,
            XXHashFactory.fastestInstance().newStreamingHash32(DEFAULT_SEED).asChecksum());
}
 

/**
 * Creates a LZ4 decoder with fastest decoder instance available on your machine.创建一个LZ4解码器，在您的机器上使用最快的解码器实例。
 *
 * @param validateChecksums  if {@code true}, the checksum field will be validated against the actual
 *                           uncompressed data, and if the checksums do not match, a suitable
 *                           {@link DecompressionException} will be thrown
 */
public Lz4FrameDecoder(boolean validateChecksums) {
    this(LZ4Factory.fastestInstance(), validateChecksums);
}