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- No-Op transformer will produce [-3, 0, 3, 42, 0, 0, 0] or [-3, 0, 9, 11, 0, 0, 0, 84, 101, 115, 116, 32, 115, 116, 114, 105, 110, 103], where 0 is a protocol version.
- Pseudo-Crypto transformer, which adds 1 to every original byte, will produce [-3, 0, 4, 43, 1, 1, 1] or [-3, 0, 10, 12, 1, 1, 1, 85, 102, 116, 117, 33, 116, 117, 115, 106, 111, 104]
- Magic-Compressor will produce [-3, 0, 7] or [-3, 0, 17], where 7 and 17 are the result of a magic compression.
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Code Block |
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language | java |
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title | Interface |
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public interface CacheObjectTransformerManager extends CacheObjectTransformerGridCacheSharedManager {
/**
* Transforms the data.
*
* @param original Original data.
* @return Transformed data (started with {@link GridBinaryMarshaller#TRANSFORMED} when restorable)
* or {@code null} when transformation is not possible/suitable.
*/
public @Nullable ByteBuffer transform(ByteBuffer original);
/**
* Restores the data.
*
* @param transformed Transformed data.
* @return Restored data.
*/
public ByteBuffer restore(ByteBuffer transformed);
/**
* Returns {@code true} when direct byte buffers are required.
*
* @return Direct flag.
*/
public boolean direct();
} |
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Every customer may implement this interface in a proper way if necessary and specify it in the via plugin configuration:
Code Block |
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language | java |
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title | Custom transformer |
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IgniteConfiguration getConfiguration() {
IgniteConfiguration cfg = ...
cfg.setCacheObjectTransformersetPluginProviders(new XXXTransformerXXXPluginProvider());
return // Which provides some XXXCacheObjectTransformerManager()
return cfg;
} |
Examples
Compression example
Code Block |
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language | java |
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title | Compression |
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class CompressionTransformer extends CacheObjectTransformerAdapter {
protected ByteBuffer transform(ByteBuffer original) throws IgniteCheckedException {
int locOverheadoverhead = 45; // OriginalTransformed length.
flag int totalOverhead = CacheObjectTransformerUtils.OVERHEAD + locOverhead;+ length.
int origSize = original.remaining();
int lim = origSize - totalOverheadoverhead;
if (lim <= 0)
return thrownull; new// IgniteCheckedException("Compression is not profitable.");
ByteBuffer compressed = byteBuffer(limoverhead + (int)Zstd.compressBound(origSize));
compressed.put(TRANSFORMED);
compressed.positionputInt(locOverheadorigSize);
int size = Zstd.compress(compressed, original, 1);
if (size >= lim)
compressed.flip();
compressed.putInt(origSize); return null; // Compression is not profitable.
compressed.rewindflip();
return compressed;
}
protected ByteBuffer restore(ByteBuffer transformed) {
ByteBuffer restored = byteBuffer(transformed.getInt());
Zstd.decompress(restored, transformed);
restored.flip();
return restored;
}
} |
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Code Block |
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language | java |
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title | Encryption |
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class EncryptionTransformer extends CacheObjectTransformerAdapter {
private static final int SHIFT = 42; // Secret!
protected ByteBuffer transform(ByteBuffer original) throws IgniteCheckedException {
ByteBuffer transformed = byteBuffer(original.remaining() + 1); // Same capacity is required.
transformed.put(TRANSFORMED);
while (original.hasRemaining())
transformed.put((byte)(original.get() + SHIFT));
transformed.flip();
return transformed;
}
protected ByteBuffer restore(ByteBuffer transformed, int length) {
ByteBuffer restored = byteBuffer(transformed.remaining()); // Same size.
while (transformed.hasRemaining())
restored.put((byte)(transformed.get() - SHIFT));
restored.flip();
return restored;
}
} |
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