/* Copyright (C) 2002 Univ. of Massachusetts Amherst, Computer Science Dept.
This file is part of "MALLET" (MAchine Learning for LanguagE Toolkit).
http://www.cs.umass.edu/~mccallum/mallet
This software is provided under the terms of the Common Public License,
version 1.0, as published by http://www.opensource.org. For further
information, see the file `LICENSE' included with this distribution. */
package cc.mallet.pipe;
import java.io.*;
import cc.mallet.types.*;
/** Convert a token sequence in the target field into a feature sequence in the target field.
@author Andrew McCallum <a href="mailto:mccallum@cs.umass.edu">mccallum@cs.umass.edu</a>
*/
public class Target2FeatureSequence extends Pipe implements Serializable
{
public Target2FeatureSequence ()
{
super (null, new Alphabet());
}
public Instance pipe (Instance carrier)
{
//Object in = carrier.getData();
Object target = carrier.getTarget();
if (target instanceof FeatureSequence)
; // Nothing to do
else if (target instanceof TokenSequence) {
TokenSequence ts = (TokenSequence) target;
FeatureSequence fs = new FeatureSequence (getTargetAlphabet(), ts.size());
for (int i = 0; i < ts.size(); i++)
fs.add (ts.get(i).getText());
carrier.setTarget(fs);
} else {
throw new IllegalArgumentException ("Unrecognized target type.");
}
return carrier;
}
// Serialization
private static final long serialVersionUID = 1;
private static final int CURRENT_SERIAL_VERSION = 0;
private void writeObject (ObjectOutputStream out) throws IOException {
out.writeInt (CURRENT_SERIAL_VERSION);
}
private void readObject (ObjectInputStream in) throws IOException, ClassNotFoundException {
int version = in.readInt ();
}
}