org.infinispan.commons.marshall.AbstractMarshaller Maven / Gradle / Ivy
package org.infinispan.commons.marshall;
import java.io.IOException;
import java.io.InputStream;
import org.infinispan.commons.io.ByteBuffer;
import org.infinispan.commons.io.ByteBufferImpl;
import org.infinispan.commons.io.LazyByteArrayOutputStream;
/**
* Abstract Marshaller implementation containing shared implementations.
*
* @author Galder Zamarreño
* @since 4.1
*/
public abstract class AbstractMarshaller implements Marshaller {
protected final MarshallableTypeHints marshallableTypeHints = new MarshallableTypeHints();
@Override
public BufferSizePredictor getBufferSizePredictor(Object o) {
return marshallableTypeHints.getBufferSizePredictor(o.getClass());
}
/**
* This is a convenience method for converting an object into a {@link org.infinispan.commons.io.ByteBuffer} which takes
* an estimated size as parameter. A {@link org.infinispan.commons.io.ByteBuffer} allows direct access to the byte
* array with minimal array copying
*
* @param o object to marshall
* @param estimatedSize an estimate of how large the resulting byte array may be
*/
protected abstract ByteBuffer objectToBuffer(Object o, int estimatedSize) throws IOException, InterruptedException;
@Override
public ByteBuffer objectToBuffer(Object obj) throws IOException, InterruptedException {
if (obj != null) {
BufferSizePredictor sizePredictor = marshallableTypeHints
.getBufferSizePredictor(obj.getClass());
int estimatedSize = sizePredictor.nextSize(obj);
ByteBuffer byteBuffer = objectToBuffer(obj, estimatedSize);
int length = byteBuffer.getLength();
// If the prediction is way off, then trim it
if (estimatedSize > (length * 4)) {
byte[] buffer = trimBuffer(byteBuffer);
byteBuffer = ByteBufferImpl.create(buffer);
}
sizePredictor.recordSize(length);
return byteBuffer;
} else {
return objectToBuffer(null, 1);
}
}
@Override
public byte[] objectToByteBuffer(Object o) throws IOException, InterruptedException {
if (o != null) {
BufferSizePredictor sizePredictor = marshallableTypeHints
.getBufferSizePredictor(o.getClass());
byte[] bytes = objectToByteBuffer(o, sizePredictor.nextSize(o));
sizePredictor.recordSize(bytes.length);
return bytes;
} else {
return objectToByteBuffer(null, 1);
}
}
@Override
public byte[] objectToByteBuffer(Object obj, int estimatedSize) throws IOException, InterruptedException {
ByteBuffer b = objectToBuffer(obj, estimatedSize);
return trimBuffer(b);
}
private byte[] trimBuffer(ByteBuffer b) {
byte[] bytes = new byte[b.getLength()];
System.arraycopy(b.getBuf(), b.getOffset(), bytes, 0, b.getLength());
return bytes;
}
@Override
public Object objectFromByteBuffer(byte[] buf) throws IOException, ClassNotFoundException {
return objectFromByteBuffer(buf, 0, buf.length);
}
/**
* This method implements {@link StreamingMarshaller#objectFromInputStream(java.io.InputStream)}, but its
* implementation has been moved here rather that keeping under a class that implements StreamingMarshaller
* in order to avoid code duplication.
*/
public Object objectFromInputStream(InputStream inputStream) throws IOException, ClassNotFoundException {
int len = inputStream.available();
LazyByteArrayOutputStream bytes;
byte[] buf;
if(len > 0) {
bytes = new LazyByteArrayOutputStream(len);
buf = new byte[Math.min(len, 1024)];
} else {
// Some input stream providers do not implement available()
bytes = new LazyByteArrayOutputStream();
buf = new byte[1024];
}
int bytesRead;
while ((bytesRead = inputStream.read(buf, 0, buf.length)) != -1) bytes.write(buf, 0, bytesRead);
return objectFromByteBuffer(bytes.getRawBuffer(), 0, bytes.size());
}
}