opennlp.tools.tokenize.WhitespaceTokenStream Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package opennlp.tools.tokenize;
import java.io.IOException;
import opennlp.tools.util.FilterObjectStream;
import opennlp.tools.util.ObjectStream;
import opennlp.tools.util.Span;
/**
* This stream formats {@link ObjectStream} of {@link TokenSample samples} into whitespace
* separated token strings.
*/
public class WhitespaceTokenStream extends FilterObjectStream {
/**
* Initializes a {@link WhitespaceTokenStream}.
*
* @param tokens The {@link ObjectStream stream} of tokens to be separated.
*/
public WhitespaceTokenStream(ObjectStream tokens) {
super(tokens);
}
@Override
public String read() throws IOException {
TokenSample tokenSample = samples.read();
if (tokenSample != null) {
StringBuilder whitespaceSeparatedTokenString = new StringBuilder();
for (Span token : tokenSample.getTokenSpans()) {
whitespaceSeparatedTokenString.append(
token.getCoveredText(tokenSample.getText()));
whitespaceSeparatedTokenString.append(' ');
}
// Shorten string by one to get rid of last space
if (whitespaceSeparatedTokenString.length() > 0) {
whitespaceSeparatedTokenString.setLength(
whitespaceSeparatedTokenString.length() - 1 );
}
return whitespaceSeparatedTokenString.toString();
}
return null;
}
}