opennlp.tools.formats.muc.DocumentSplitterStream 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.formats.muc;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import opennlp.tools.util.FilterObjectStream;
import opennlp.tools.util.InvalidFormatException;
import opennlp.tools.util.ObjectStream;
class DocumentSplitterStream extends FilterObjectStream {
private static final String DOC_START_ELEMENT = "";
private static final String DOC_END_ELEMENT = " ";
private final List docs = new ArrayList<>();
DocumentSplitterStream(ObjectStream samples) {
super(samples);
}
@Override
public String read() throws IOException {
if (docs.isEmpty()) {
String newDocs = samples.read();
if (newDocs != null) {
int docStartOffset = 0;
while (true) {
int startDocElement = newDocs.indexOf(DOC_START_ELEMENT, docStartOffset);
int endDocElement = newDocs.indexOf(DOC_END_ELEMENT, docStartOffset);
if (startDocElement != -1 && endDocElement != -1) {
if (startDocElement < endDocElement) {
docs.add(newDocs.substring(startDocElement, endDocElement + DOC_END_ELEMENT.length()));
docStartOffset = endDocElement + DOC_END_ELEMENT.length();
}
else {
throw new InvalidFormatException(" element is not closed!");
}
}
else if (startDocElement != endDocElement) {
throw new InvalidFormatException("Missing or element!");
}
else {
break;
}
}
}
}
if (docs.size() > 0) {
return docs.remove(0);
}
else {
return null;
}
}
}