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* 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
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package org.apache.lucene.search.uhighlight;
import org.elasticsearch.test.ESTestCase;
import java.text.BreakIterator;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import static org.hamcrest.Matchers.greaterThan;
import static org.hamcrest.Matchers.greaterThanOrEqualTo;
import static org.hamcrest.Matchers.lessThanOrEqualTo;
public class BoundedBreakIteratorScannerTests extends ESTestCase {
private static final String[] WORD_BOUNDARIES =
new String[] { " ", " ", "\t", "#", "\n" };
private static final String[] SENTENCE_BOUNDARIES =
new String[] { "! ", "? ", ". ", ".\n", ".\n\n" };
private void testRandomAsciiTextCase(BreakIterator bi, int maxLen) {
// Generate a random set of unique terms with ascii character
int maxSize = randomIntBetween(5, 100);
String[] vocabulary = new String[maxSize];
for (int i = 0; i < maxSize; i++) {
if (rarely()) {
vocabulary[i] = randomAlphaOfLengthBetween(50, 200);
} else {
vocabulary[i] = randomAlphaOfLengthBetween(1, 30);
}
}
// Generate a random text made of random terms separated with word-boundaries
// and sentence-boundaries.
StringBuilder text = new StringBuilder();
List<Integer> offsetList = new ArrayList<> ();
List<Integer> sizeList = new ArrayList<> ();
// the number of sentences to generate
int numSentences = randomIntBetween(10, 100);
int maxTermLen = 0;
for (int i = 0; i < numSentences; i++) {
// the number of terms in the sentence
int numTerms = randomIntBetween(5, 10);
for (int j = 0; j < numTerms; j++) {
int termId = randomIntBetween(0, vocabulary.length - 1);
String term = vocabulary[termId].toLowerCase(Locale.ROOT);
if (j == 0) {
// capitalize the first letter of the first term in the sentence
term = term.substring(0, 1).toUpperCase(Locale.ROOT) + term.substring(1);
} else {
String sep = randomFrom(WORD_BOUNDARIES);
text.append(sep);
}
maxTermLen = Math.max(term.length(), maxTermLen);
offsetList.add(text.length());
sizeList.add(term.length());
text.append(term);
}
String boundary = randomFrom(SENTENCE_BOUNDARIES);
text.append(boundary);
}
int[] sizes = sizeList.stream().mapToInt(i->i).toArray();
int[] offsets = offsetList.stream().mapToInt(i->i).toArray();
bi.setText(text.toString());
int currentPos = randomIntBetween(0, 20);
int lastEnd = -1;
int maxPassageLen = maxLen+(maxTermLen*2);
while (currentPos < offsets.length) {
// find the passage that contains the current term
int nextOffset = offsets[currentPos];
int start = bi.preceding(nextOffset+1);
int end = bi.following(nextOffset);
// check that the passage is valid
assertThat(start, greaterThanOrEqualTo(lastEnd));
assertThat(end, greaterThan(start));
assertThat(start, lessThanOrEqualTo(nextOffset));
assertThat(end, greaterThanOrEqualTo(nextOffset));
int passageLen = end-start;
assertThat(passageLen, lessThanOrEqualTo(maxPassageLen));
// checks that the start and end of the passage are on word boundaries.
int startPos = Arrays.binarySearch(offsets, start);
int endPos = Arrays.binarySearch(offsets, end);
if (startPos < 0) {
int lastWordEnd =
offsets[Math.abs(startPos)-2] + sizes[Math.abs(startPos)-2];
assertThat(start, greaterThanOrEqualTo(lastWordEnd));
}
if (endPos < 0) {
if (Math.abs(endPos)-2 < offsets.length) {
int lastWordEnd =
offsets[Math.abs(endPos) - 2] + sizes[Math.abs(endPos) - 2];
assertThat(end, greaterThanOrEqualTo(lastWordEnd));
}
// advance the position to the end of the current passage
currentPos = (Math.abs(endPos) - 1);
} else {
// advance the position to the end of the current passage
currentPos = endPos;
}
// randomly advance to the next term to highlight
currentPos += randomIntBetween(0, 20);
lastEnd = end;
}
}
public void testBoundedSentence() {
for (int i = 0; i < 20; i++) {
int maxLen = randomIntBetween(10, 500);
testRandomAsciiTextCase(
BoundedBreakIteratorScanner.getSentence(Locale.ROOT, maxLen),
maxLen
);
}
}
}