opennlp.tools.util.ParagraphStream 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.util;
import java.io.IOException;
/**
* A {@link FilterObjectStream} which merges text lines into paragraphs.
*
* The boundary of paragraph is defined by an empty text line.
* If the last paragraph in the stream is not terminated by an empty line
* the left over is assumed to be a paragraph.
*/
public class ParagraphStream extends FilterObjectStream {
/**
* Initializes an {@link FilterObjectStream}.
*
* @param lineStream The {@link ObjectStream stream} of samples.
*/
public ParagraphStream(ObjectStream lineStream) {
super(lineStream);
}
@Override
public String read() throws IOException {
StringBuilder paragraph = new StringBuilder();
while (true) {
String line = samples.read();
// The last paragraph in the input might not
// be terminated well with a new line at the end.
if (line == null || line.isEmpty()) {
if (paragraph.length() > 0) {
return paragraph.toString();
}
}
else {
paragraph.append(line).append('\n');
}
if (line == null)
return null;
}
}
}