Session: Querying: How to use Highlighting

Highlighting can be a great feature for increasing search UX. To take leverage of it use highlight method.

Syntax

IDocumentQuery<T> highlight(String fieldName,
                            int fragmentLength,
                            int fragmentCount,
                            Reference<Highlightings> highlightings);

IDocumentQuery<T> highlight(String fieldName,
                            int fragmentLength,
                            int fragmentCount,
                            HighlightingOptions options,
                            Reference<Highlightings> highlightings);

Options

private String groupKey;
private String[] preTags;
private String[] postTags;

// getters and setters

Example

Reference<Highlightings> highlightingsRef = new Reference<>();
List<SearchItem> results = session
    .query(SearchItem.class, ContentSearchIndex.class)
    .highlight("text", 128, 1, highlightingsRef)
    .search("text", "raven")
    .toList();

StringBuilder builder = new StringBuilder();
builder.append("<ul>");

for (SearchItem result : results) {
    String[] fragments = highlightingsRef.value.getFragments(result.getId());
    builder.append("<li>")
        .append(fragments[0])
        .append("</li>");
}

builder.append("</ul>");
String ul = builder.toString();

from index 'ContentSearchIndex'
where search(text, 'raven')
include highlight(text, 128, 1)

Remarks