mirror of https://github.com/apache/lucene.git
LUCENE-9093: UnifiedHighlighter LengthGoalBreakIterator frag align
Matches in passages should be centered better on average. Closes #1123
This commit is contained in:
Nándor Mátravölgyi
David Smiley
parent
1851779ddb
commit
4c9cc2cefd
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@ -83,7 +83,10 @@ Other
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API Changes
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---------------------
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(No changes)
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* LUCENE-9093: Not an API change but a change in behavior of the UnifiedHighlighter's LengthGoalBreakIterator that will
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yield Passages sized a little different due to the fact that the sizing pivot is now the center of the first match and
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not its left edge.
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New Features
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---------------------
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@ -106,6 +109,10 @@ Improvements
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* LUCENE-9106: UniformSplit postings format allows extension of block/line serializers. (Bruno Roustant)
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* LUCENE-9093: UnifiedHighlighter's LengthGoalBreakIterator has a new fragmentAlignment option to better center the
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first match in the passage. Also the sizing point now pivots at the center of the first match term and not its left
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edge. This yields Passages that won't be identical to the previous behavior. (Nándor Mátravölgyi, David Smiley)
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Optimizations
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---------------------
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(No changes)
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@ -141,6 +141,7 @@ public class FieldHighlighter {
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}
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});
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Passage passage = new Passage(); // the current passage in-progress. Will either get reset or added to queue.
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int lastPassageEnd = 0;
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do {
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int start = off.startOffset();
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@ -158,9 +159,12 @@ public class FieldHighlighter {
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if (start >= contentLength) {
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break;
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}
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// find fragment from the middle of the match, so the result's length may be closer to fragsize
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final int center = start + (end - start) / 2;
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// advance breakIterator
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passage.setStartOffset(Math.max(this.breakIterator.preceding(start + 1), 0));
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passage.setEndOffset(Math.min(this.breakIterator.following(start), contentLength));
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passage.setStartOffset(Math.min(start, Math.max(this.breakIterator.preceding(Math.max(start + 1, center)), lastPassageEnd)));
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lastPassageEnd = Math.max(end, Math.min(this.breakIterator.following(Math.min(end - 1, center)), contentLength));
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passage.setEndOffset(lastPassageEnd);
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}
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// Add this term to the passage.
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BytesRef term = off.getTerm();// a reference; safe to refer to
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@ -33,22 +33,49 @@ public class LengthGoalBreakIterator extends BreakIterator {
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private final BreakIterator baseIter;
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private final int lengthGoal;
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private final float fragmentAlignment; // how much text to align before match-fragment, valid in range [0, 1]
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private final boolean isMinimumLength; // if false then is "closest to" length
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private int currentCache;
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/** Breaks will be at least {@code minLength} apart (to the extent possible). */
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/**
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* Breaks will be at least {@code minLength} apart (to the extent possible),
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* while trying to position the match inside the fragment according to {@code fragmentAlignment}.
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*/
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public static LengthGoalBreakIterator createMinLength(BreakIterator baseIter, int minLength,
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float fragmentAlignment) {
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return new LengthGoalBreakIterator(baseIter, minLength, fragmentAlignment, true, baseIter.current());
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}
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/** For backwards compatibility you can initialise the break iterator without fragmentAlignment. */
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@Deprecated
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public static LengthGoalBreakIterator createMinLength(BreakIterator baseIter, int minLength) {
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return new LengthGoalBreakIterator(baseIter, minLength, true);
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return createMinLength(baseIter, minLength, 0.f);
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}
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/** Breaks will be on average {@code targetLength} apart; the closest break to this target (before or after)
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* is chosen. */
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/**
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* Breaks will be on average {@code targetLength} apart; the closest break to this target (before or after)
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* is chosen. The match will be positioned according to {@code fragmentAlignment} as much as possible.
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*/
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public static LengthGoalBreakIterator createClosestToLength(BreakIterator baseIter, int targetLength,
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float fragmentAlignment) {
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return new LengthGoalBreakIterator(baseIter, targetLength, fragmentAlignment, false, baseIter.current());
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}
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/** For backwards compatibility you can initialise the break iterator without fragmentAlignment. */
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@Deprecated
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public static LengthGoalBreakIterator createClosestToLength(BreakIterator baseIter, int targetLength) {
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return new LengthGoalBreakIterator(baseIter, targetLength, false);
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return createClosestToLength(baseIter, targetLength, 0.f);
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}
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private LengthGoalBreakIterator(BreakIterator baseIter, int lengthGoal, boolean isMinimumLength) {
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private LengthGoalBreakIterator(BreakIterator baseIter, int lengthGoal, float fragmentAlignment,
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boolean isMinimumLength, int currentCache) {
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this.baseIter = baseIter;
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this.currentCache = currentCache;
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this.lengthGoal = lengthGoal;
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if (fragmentAlignment < 0.f || fragmentAlignment > 1.f || !Float.isFinite(fragmentAlignment)) {
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throw new IllegalArgumentException("fragmentAlignment must be >= zero and <= one");
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}
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this.fragmentAlignment = fragmentAlignment;
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this.isMinimumLength = isMinimumLength;
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}
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@ -60,12 +87,15 @@ public class LengthGoalBreakIterator extends BreakIterator {
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@Override
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public String toString() {
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String goalDesc = isMinimumLength ? "minLen" : "targetLen";
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return getClass().getSimpleName() + "{" + goalDesc + "=" + lengthGoal + ", baseIter=" + baseIter + "}";
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return getClass().getSimpleName() + "{" + goalDesc + "=" + lengthGoal + ", fragAlign=" + fragmentAlignment +
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", baseIter=" + baseIter + "}";
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}
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@Override
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public Object clone() {
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return new LengthGoalBreakIterator((BreakIterator) baseIter.clone(), lengthGoal, isMinimumLength);
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return new LengthGoalBreakIterator(
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(BreakIterator) baseIter.clone(), lengthGoal, fragmentAlignment, isMinimumLength, currentCache
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);
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}
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@Override
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@ -76,26 +106,28 @@ public class LengthGoalBreakIterator extends BreakIterator {
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@Override
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public void setText(String newText) {
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baseIter.setText(newText);
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currentCache = baseIter.current();
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}
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@Override
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public void setText(CharacterIterator newText) {
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baseIter.setText(newText);
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currentCache = baseIter.current();
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}
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@Override
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public int current() {
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return baseIter.current();
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return currentCache;
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}
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@Override
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public int first() {
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return baseIter.first();
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return currentCache = baseIter.first();
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}
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@Override
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public int last() {
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return baseIter.last();
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return currentCache = baseIter.last();
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}
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@Override
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@ -104,10 +136,10 @@ public class LengthGoalBreakIterator extends BreakIterator {
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return baseIter.next(n); // probably wrong
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}
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// called by getSummaryPassagesNoHighlight to generate default summary.
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// Called by getSummaryPassagesNoHighlight to generate default summary.
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@Override
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public int next() {
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return following(current());
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return following(currentCache, currentCache + lengthGoal);
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}
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@Override
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@ -116,65 +148,70 @@ public class LengthGoalBreakIterator extends BreakIterator {
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return baseIter.previous();
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}
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// called while the current position is the start of a new passage; find end of passage
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@Override
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public int following(int followingIdx) {
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final int startIdx = current();
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if (followingIdx < startIdx) {
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assert false : "Not supported";
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return baseIter.following(followingIdx);
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}
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final int targetIdx = startIdx + lengthGoal;
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// When followingIdx >= targetIdx, we can simply delegate since it will be >= the target
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if (followingIdx >= targetIdx - 1) {
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return baseIter.following(followingIdx);
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}
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// If target exceeds the text length, return the last index.
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if (targetIdx >= getText().getEndIndex()) {
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return baseIter.last();
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public int following(int matchEndIndex) {
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return following(matchEndIndex, (matchEndIndex + 1) + (int)(lengthGoal * (1.f - fragmentAlignment)));
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}
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// Find closest break >= the target
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private int following(int matchEndIndex, int targetIdx) {
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if (targetIdx >= getText().getEndIndex()) {
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if (currentCache == baseIter.last()) {
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return DONE;
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}
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return currentCache = baseIter.last();
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}
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final int afterIdx = baseIter.following(targetIdx - 1);
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if (afterIdx == DONE) { // we're at the end; can this happen?
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return current();
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if (afterIdx == DONE) {
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currentCache = baseIter.last();
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return DONE;
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}
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if (afterIdx == targetIdx) { // right on the money
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return afterIdx;
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return currentCache = afterIdx;
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}
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if (isMinimumLength) { // thus never undershoot
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return afterIdx;
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return currentCache = afterIdx;
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}
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// note: it is a shame that we invoke preceding() *in addition to* following(); BI's are sometimes expensive.
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// note: it is a shame that we invoke preceding() *one more time*; BI's are sometimes expensive.
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// Find closest break < target
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final int beforeIdx = baseIter.preceding(targetIdx); // or could do baseIter.previous() but we hope the BI implements preceding()
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if (beforeIdx <= followingIdx) { // too far back
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return moveToBreak(afterIdx);
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// Find closest break to target
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final int beforeIdx = baseIter.preceding(targetIdx);
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if (targetIdx - beforeIdx < afterIdx - targetIdx && beforeIdx > matchEndIndex) {
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return currentCache = beforeIdx;
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}
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if (targetIdx - beforeIdx <= afterIdx - targetIdx) {
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return beforeIdx;
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}
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return moveToBreak(afterIdx);
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}
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private int moveToBreak(int idx) { // precondition: idx is a known break
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// bi.isBoundary(idx) has side-effect of moving the position. Not obvious!
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//boolean moved = baseIter.isBoundary(idx); // probably not particularly expensive
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//assert moved && current() == idx;
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// TODO fix: Would prefer to do "- 1" instead of "- 2" but CustomSeparatorBreakIterator has a bug.
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int current = baseIter.following(idx - 2);
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assert current == idx : "following() didn't move us to the expected index.";
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return idx;
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return currentCache = afterIdx;
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}
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// called at start of new Passage given first word start offset
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@Override
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public int preceding(int offset) {
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return baseIter.preceding(offset); // no change needed
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public int preceding(int matchStartIndex) {
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final int targetIdx = (matchStartIndex - 1) - (int)(lengthGoal * fragmentAlignment);
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if (targetIdx <= 0) {
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if (currentCache == baseIter.first()) {
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return DONE;
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}
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return currentCache = baseIter.first();
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}
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final int beforeIdx = baseIter.preceding(targetIdx + 1);
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if (beforeIdx == DONE) {
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currentCache = baseIter.first();
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return DONE;
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}
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if (beforeIdx == targetIdx) { // right on the money
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return currentCache = beforeIdx;
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}
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if (isMinimumLength) { // thus never undershoot
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return currentCache = beforeIdx;
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}
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// note: it is a shame that we invoke following() *one more time*; BI's are sometimes expensive.
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// Find closest break to target
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final int afterIdx = baseIter.following(targetIdx - 1);
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if (afterIdx - targetIdx < targetIdx - beforeIdx && afterIdx < matchStartIndex) {
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return currentCache = afterIdx;
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}
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return currentCache = beforeIdx;
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}
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@Override
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@ -18,6 +18,7 @@
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package org.apache.lucene.search.uhighlight;
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import java.io.IOException;
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import java.text.BreakIterator;
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import org.apache.lucene.analysis.Analyzer;
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import org.apache.lucene.analysis.MockAnalyzer;
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@ -28,6 +29,7 @@ import org.apache.lucene.util.QueryBuilder;
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public class LengthGoalBreakIteratorTest extends LuceneTestCase {
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private static final String FIELD = "body";
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private static final float[] ALIGNS = {0.f, 0.5f, 1.f};
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// We test LengthGoalBreakIterator as it is used by the UnifiedHighlighter instead of directly, because it is
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// not a general purpose BreakIterator. A unit test of it directly wouldn't give as much confidence.
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@ -39,65 +41,159 @@ public class LengthGoalBreakIteratorTest extends LuceneTestCase {
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// 0 1
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// 01234567890123456789
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static final String CONTENT = "Aa bb. Cc dd. Ee ff";
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static final String CONTENT2 = "Aa bb Cc dd X Ee ff Gg hh.";
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static final String CONTENT3 = "Aa bbcc ddxyzee ffgg hh.";
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public void testFragmentAlignmentConstructor() throws IOException {
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BreakIterator baseBI = new CustomSeparatorBreakIterator('.');
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// test fragmentAlignment validation
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float[] valid_aligns = {0.f, 0.3333f, 0.5f, 0.99f, 1.f};
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for (float alignment : valid_aligns) {
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LengthGoalBreakIterator.createClosestToLength(baseBI, 50, alignment);
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}
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float[] invalid_aligns = {-0.01f, -1.f, 1.5f, Float.NaN, Float.NEGATIVE_INFINITY, Float.POSITIVE_INFINITY};
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for (float alignment : invalid_aligns) {
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expectThrows(IllegalArgumentException.class, () -> {
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LengthGoalBreakIterator.createClosestToLength(baseBI, 50, alignment);
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});
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}
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// test backwards compatibility constructors
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String backwardCompString = LengthGoalBreakIterator.createClosestToLength(baseBI, 50).toString();
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assertTrue(backwardCompString, backwardCompString.contains("fragAlign=0.0"));
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backwardCompString = LengthGoalBreakIterator.createMinLength(baseBI, 50).toString();
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assertTrue(backwardCompString, backwardCompString.contains("fragAlign=0.0"));
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}
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public void testTargetLen() throws IOException {
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// "goal" means target length goal to find closest break
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// at first word:
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Query query = query("aa");
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assertEquals("almost two sent",
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"<b>Aa</b> bb.", highlightClosestToLen(CONTENT, query, 9));
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assertEquals( "barely two sent",
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"<b>Aa</b> bb. Cc dd.", highlightClosestToLen(CONTENT, query, 10));
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assertEquals("long goal",
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"<b>Aa</b> bb. Cc dd. Ee ff", highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20)));
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assertEquals("almost two sent A",
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"<b>Aa</b> bb.", highlightClosestToLen(CONTENT, query, 7, 0.f));
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assertEquals("almost two sent B",
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"<b>Aa</b> bb.", highlightClosestToLen(CONTENT, query, 15, 0.5f));
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assertEquals("almost two sent C",
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"<b>Aa</b> bb.", highlightClosestToLen(CONTENT, query, 64, 1.f));
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assertEquals("barely two sent A",
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"<b>Aa</b> bb. Cc dd.", highlightClosestToLen(CONTENT, query, 8, 0.f));
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assertEquals("barely two sent B",
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"<b>Aa</b> bb. Cc dd.", highlightClosestToLen(CONTENT, query, 16, 0.5f));
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assertEquals("long goal A",
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"<b>Aa</b> bb. Cc dd. Ee ff", highlightClosestToLen(CONTENT, query, 14 + random().nextInt(20), 0.f));
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assertEquals("long goal B",
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"<b>Aa</b> bb. Cc dd. Ee ff", highlightClosestToLen(CONTENT, query, 28 + random().nextInt(20), 0.5f));
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// at some word not at start of passage
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query = query("dd");
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assertEquals("short goal",
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" Cc <b>dd</b>.", highlightClosestToLen(CONTENT, query, random().nextInt(5)));
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assertEquals("almost two sent",
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" Cc <b>dd</b>.", highlightClosestToLen(CONTENT, query, 10));
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assertEquals("barely two sent",
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" Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 11));
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assertEquals("long goal",
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" Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 12 + random().nextInt(20)));
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for (float align : ALIGNS) {
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// alignment is not meaningful if fragsize is shorter than or closer to match-fragment boundaries
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assertEquals("short goal " + align,
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" Cc <b>dd</b>.", highlightClosestToLen(CONTENT, query, random().nextInt(4), align));
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}
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// preceding/following inclusion by alignment parameter
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assertEquals("barely two sent A",
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" Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 11, 0.f));
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assertEquals("barely two sent B",
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" Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 11, 0.5f));
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assertEquals("barely two sent C",
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"Aa bb. Cc <b>dd</b>.", highlightClosestToLen(CONTENT, query, 11, 1.f));
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assertEquals("long goal A",
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" Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20), 0.f));
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assertEquals("long goal B",
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"Aa bb. Cc <b>dd</b>. Ee ff", highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20), 0.5f));
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assertEquals("long goal C",
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"Aa bb. Cc <b>dd</b>.", highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20), 1.f));
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query = query("ddxyzee");
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assertEquals("test fragment search from the middle of the match; almost including",
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"<b>ddxyzee</b> ", highlightClosestToLen(CONTENT3, query, 7, 0.5f, 1, ' '));
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assertEquals("test fragment search from the middle of the match; barely including",
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"bbcc <b>ddxyzee</b> ffgg ", highlightClosestToLen(CONTENT3, query, 14, 0.5f, 1, ' '));
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}
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public void testMinLen() throws IOException {
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// minLen mode is simpler than targetLen... just test a few cases
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Query query = query("dd");
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assertEquals("almost two sent",
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" Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 6));
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assertEquals("barely two sent",
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" Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 7));
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assertEquals("almost two sent A",
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" Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 0, 0.f));
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assertEquals("almost two sent B",
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" Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 1, 0.5f));
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assertEquals("almost two sent C",
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" Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 5, 1.f));
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assertEquals("barely two sent A",
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" Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 1, 0.f));
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assertEquals("barely two sent B",
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" Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 2, 0.5f));
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assertEquals("barely two sent C",
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"Aa bb. Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 7, 1.f));
|
||||
assertEquals("barely two sent D/a",
|
||||
" Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 2, 0.55f));
|
||||
assertEquals("barely two sent D/b",
|
||||
" Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 3, 0.55f));
|
||||
assertEquals("barely two sent E/a",
|
||||
" Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 10, 0.5f));
|
||||
assertEquals("barely two sent E/b",
|
||||
"Aa bb. Cc <b>dd</b>. Ee ff", highlightMinLen(CONTENT, query, 10, 0.7f));
|
||||
assertEquals("barely two sent E/c",
|
||||
"Aa bb. Cc <b>dd</b>.", highlightMinLen(CONTENT, query, 9, 0.9f));
|
||||
|
||||
query = query("ddxyzee");
|
||||
assertEquals("test fragment search from the middle of the match; almost including",
|
||||
"<b>ddxyzee</b> ", highlightMinLen(CONTENT3, query, 7, 0.5f, ' '));
|
||||
assertEquals("test fragment search from the middle of the match; barely including",
|
||||
"bbcc <b>ddxyzee</b> ffgg ", highlightMinLen(CONTENT3, query, 8, 0.5f, ' '));
|
||||
}
|
||||
|
||||
public void testMinLenPrecision() throws IOException {
|
||||
Query query = query("x");
|
||||
assertEquals("test absolute minimal length",
|
||||
"<b>X</b> ", highlightMinLen(CONTENT2, query, 1, 0.5f, ' '));
|
||||
assertEquals("test slightly above minimal length",
|
||||
"dd <b>X</b> Ee ", highlightMinLen(CONTENT2, query, 4, 0.5f, ' '));
|
||||
}
|
||||
|
||||
public void testDefaultSummaryTargetLen() throws IOException {
|
||||
Query query = query("zz");
|
||||
for (float align : ALIGNS) { // alignment is not used for creating default-summary
|
||||
assertEquals("Aa bb.",
|
||||
highlightClosestToLen(CONTENT, query, random().nextInt(10))); // < 10
|
||||
highlightClosestToLen(CONTENT, query, 6 + random().nextInt(4), align));
|
||||
assertEquals("Aa bb. Cc dd.",
|
||||
highlightClosestToLen(CONTENT, query, 10 + 6)); // cusp of adding 3rd sentence
|
||||
highlightClosestToLen(CONTENT, query, 12 + random().nextInt(4), align));
|
||||
assertEquals("Aa bb. Cc dd. Ee ff",
|
||||
highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20))); // >= 14
|
||||
highlightClosestToLen(CONTENT, query, 17 + random().nextInt(20), align));
|
||||
}
|
||||
assertEquals("Aa bb. Cc dd.",
|
||||
highlightClosestToLen(CONTENT, query, 6 + random().nextInt(4), 0.f, 2));
|
||||
}
|
||||
|
||||
private Query query(String qStr) {
|
||||
return new QueryBuilder(analyzer).createBooleanQuery(FIELD, qStr);
|
||||
}
|
||||
|
||||
private String highlightClosestToLen(String content, Query query, int lengthGoal) throws IOException {
|
||||
UnifiedHighlighter highlighter = new UnifiedHighlighter(null, analyzer);
|
||||
highlighter.setBreakIterator(() -> LengthGoalBreakIterator.createClosestToLength(new CustomSeparatorBreakIterator('.'), lengthGoal));
|
||||
return highlighter.highlightWithoutSearcher(FIELD, query, content, 1).toString();
|
||||
private String highlightClosestToLen(String content, Query query, int lengthGoal, float fragAlign) throws IOException {
|
||||
return highlightClosestToLen(content, query, lengthGoal, fragAlign, 1);
|
||||
}
|
||||
|
||||
private String highlightMinLen(String content, Query query, int lengthGoal) throws IOException {
|
||||
private String highlightClosestToLen(String content, Query query, int lengthGoal, float fragAlign, int maxPassages) throws IOException {
|
||||
return highlightClosestToLen(content, query, lengthGoal, fragAlign, maxPassages, '.');
|
||||
}
|
||||
|
||||
private String highlightClosestToLen(String content, Query query, int lengthGoal, float fragAlign, int maxPassages, char separator) throws IOException {
|
||||
UnifiedHighlighter highlighter = new UnifiedHighlighter(null, analyzer);
|
||||
highlighter.setBreakIterator(() -> LengthGoalBreakIterator.createClosestToLength(new CustomSeparatorBreakIterator(separator), lengthGoal, fragAlign));
|
||||
return highlighter.highlightWithoutSearcher(FIELD, query, content, maxPassages).toString();
|
||||
}
|
||||
|
||||
private String highlightMinLen(String content, Query query, int lengthGoal, float fragAlign) throws IOException {
|
||||
return highlightMinLen(content, query, lengthGoal, fragAlign, '.');
|
||||
}
|
||||
|
||||
private String highlightMinLen(String content, Query query, int lengthGoal, float fragAlign, char separator) throws IOException {
|
||||
// differs from above only by "createMinLength"
|
||||
UnifiedHighlighter highlighter = new UnifiedHighlighter(null, analyzer);
|
||||
highlighter.setBreakIterator(() -> LengthGoalBreakIterator.createMinLength(new CustomSeparatorBreakIterator('.'), lengthGoal));
|
||||
highlighter.setBreakIterator(() -> LengthGoalBreakIterator.createMinLength(new CustomSeparatorBreakIterator(separator), lengthGoal, fragAlign));
|
||||
return highlighter.highlightWithoutSearcher(FIELD, query, content, 1).toString();
|
||||
}
|
||||
}
|
||||
|
|
@ -184,6 +184,10 @@ Improvements
|
|||
|
||||
* SOLR-14129: Reuse Jackson ObjectMapper in AuditLoggerPlugin (janhoy)
|
||||
|
||||
* LUCENE-9093: The Unified highlighter has two new passage sizing parameters, hl.fragAlignRatio and
|
||||
hl.fragsizeIsMinimum, with defaults that aim to better center matches in fragments than previously. See the ref guide.
|
||||
Regardless of the settings, the passages may be sized differently than before. (Nándor Mátravölgyi, David Smiley)
|
||||
|
||||
Optimizations
|
||||
---------------------
|
||||
(No changes)
|
||||
|
|
|
|||
|
|
@ -326,8 +326,11 @@ public class UnifiedSolrHighlighter extends SolrHighlighter implements PluginInf
|
|||
if (fragsize <= 1) { // no real minimum size
|
||||
return baseBI;
|
||||
}
|
||||
return LengthGoalBreakIterator.createMinLength(baseBI, fragsize);
|
||||
// TODO option for using createClosestToLength()
|
||||
float fragalign = params.getFieldFloat(field, HighlightParams.FRAGALIGNRATIO, 0.5f);
|
||||
if (params.getFieldBool(field, HighlightParams.FRAGSIZEISMINIMUM, false)) {
|
||||
return LengthGoalBreakIterator.createMinLength(baseBI, fragsize, fragalign);
|
||||
}
|
||||
return LengthGoalBreakIterator.createClosestToLength(baseBI, fragsize, fragalign);
|
||||
}
|
||||
|
||||
/**
|
||||
|
|
|
|||
|
|
@ -251,8 +251,17 @@ public class TestUnifiedSolrHighlighter extends SolrTestCaseJ4 {
|
|||
req("q", "text:document", "sort", "id asc", "hl", "true", "hl.bs.type", "SEPARATOR","hl.bs.separator","#","hl.fragsize", "-1"),
|
||||
"//lst[@name='highlighting']/lst[@name='104']/arr[@name='text']/str='While the other <em>document</em> contains the same #'");
|
||||
|
||||
assertQ("CUSTOM breakiterator with fragsize 70 minimum",
|
||||
req("q", "text:document", "sort", "id asc", "hl", "true", "hl.bs.type", "SEPARATOR","hl.bs.separator","#","hl.fragsize", "70", "hl.fragsizeIsMinimum", "true"),
|
||||
"//lst[@name='highlighting']/lst[@name='103']/arr[@name='text']/str='This <em>document</em> contains # special characters, while the other <em>document</em> contains the same #'");
|
||||
assertQ("CUSTOM breakiterator with fragsize 70",
|
||||
req("q", "text:document", "sort", "id asc", "hl", "true", "hl.bs.type", "SEPARATOR","hl.bs.separator","#","hl.fragsize", "70"),
|
||||
"//lst[@name='highlighting']/lst[@name='103']/arr[@name='text']/str='This <em>document</em> contains #'");
|
||||
assertQ("CUSTOM breakiterator with fragsize 90",
|
||||
req("q", "text:document", "sort", "id asc", "hl", "true", "hl.bs.type", "SEPARATOR","hl.bs.separator","#","hl.fragsize", "90"),
|
||||
"//lst[@name='highlighting']/lst[@name='103']/arr[@name='text']/str='This <em>document</em> contains #'");
|
||||
assertQ("CUSTOM breakiterator with fragsize 100",
|
||||
req("q", "text:document", "sort", "id asc", "hl", "true", "hl.bs.type", "SEPARATOR","hl.bs.separator","#","hl.fragsize", "100"),
|
||||
"//lst[@name='highlighting']/lst[@name='103']/arr[@name='text']/str='This <em>document</em> contains # special characters, while the other <em>document</em> contains the same #'");
|
||||
}
|
||||
|
||||
|
|
@ -262,11 +271,17 @@ public class TestUnifiedSolrHighlighter extends SolrTestCaseJ4 {
|
|||
assertU(adoc("id", "10", "text", "This is a sentence just under seventy chars in length blah blah. Next sentence is here."));
|
||||
assertU(commit());
|
||||
assertQ("default fragsize",
|
||||
req("q", "text:seventy", "hl", "true"),
|
||||
req("q", "text:seventy", "hl", "true", "hl.fragsizeIsMinimum", "true"),
|
||||
"//lst[@name='highlighting']/lst[@name='10']/arr[@name='text']/str='This is a sentence just under <em>seventy</em> chars in length blah blah. Next sentence is here.'");
|
||||
assertQ("smaller fragsize",
|
||||
req("q", "text:seventy", "hl", "true", "hl.fragsize", "60"), // a bit smaller
|
||||
assertQ("default fragsize",
|
||||
req("q", "text:seventy", "hl", "true", "hl.fragsizeIsMinimum", "true", "hl.fragsize", "60"),
|
||||
"//lst[@name='highlighting']/lst[@name='10']/arr[@name='text']/str='This is a sentence just under <em>seventy</em> chars in length blah blah. '");
|
||||
assertQ("smaller fragsize",
|
||||
req("q", "text:seventy", "hl", "true"),
|
||||
"//lst[@name='highlighting']/lst[@name='10']/arr[@name='text']/str='This is a sentence just under <em>seventy</em> chars in length blah blah. '");
|
||||
assertQ("default fragsize",
|
||||
req("q", "text:seventy", "hl", "true", "hl.fragsize", "90"),
|
||||
"//lst[@name='highlighting']/lst[@name='10']/arr[@name='text']/str='This is a sentence just under <em>seventy</em> chars in length blah blah. Next sentence is here.'");
|
||||
}
|
||||
|
||||
public void testEncoder() {
|
||||
|
|
|
|||
|
|
@ -225,6 +225,14 @@ By default, the Unified Highlighter will usually pick the right offset source (s
|
|||
+
|
||||
The offset source can be explicitly configured to one of: `ANALYSIS`, `POSTINGS`, `POSTINGS_WITH_TERM_VECTORS`, or `TERM_VECTORS`.
|
||||
|
||||
`hl.fragAlignRatio`::
|
||||
Fragment alignment can influence where the match in a passage is positioned. This floating point value is used to break the `hl.fragsize` around the match. The default value of `0.5` means to align the match to the middle. A value of `0.0` would mean to align the match to the left, while `1.0` to align it to the right. _Note: there are situations where the requested alignment is not plausible. This depends on the length of the match, the used breakiterator and the text content around the match._
|
||||
|
||||
`hl.fragsizeIsMinimum`::
|
||||
By default this parameter is `false`. In this case the highlighter will accept a shorter fragment than `hl.fragsize`, if that is closer to the target than what the next longer choice would be.
|
||||
+
|
||||
When treating `hl.fragsize` as a strict minimum length is acceptable, turning this on has some performance benefits to consider.
|
||||
|
||||
`hl.tag.ellipsis`::
|
||||
By default, each snippet is returned as a separate value (as is done with the other highlighters). Set this parameter to instead return one string with this text as the delimiter. _Note: this is likely to be removed in the future._
|
||||
|
||||
|
|
|
|||
|
|
@ -47,6 +47,8 @@ public interface HighlightParams {
|
|||
|
||||
// sizing
|
||||
public static final String FRAGSIZE = HIGHLIGHT+".fragsize"; // OH, FVH, UH
|
||||
public static final String FRAGSIZEISMINIMUM = HIGHLIGHT+".fragsizeIsMinimum"; // UH
|
||||
public static final String FRAGALIGNRATIO = HIGHLIGHT+".fragAlignRatio"; // UH
|
||||
public static final String FRAGMENTER = HIGHLIGHT+".fragmenter"; // OH
|
||||
public static final String INCREMENT = HIGHLIGHT+".increment"; // OH
|
||||
public static final String REGEX = "regex"; // OH
|
||||
|
|
|
|||
Loading…
Reference in New Issue