Search and Highlight Text in Documents Using GroupDocs.Search for Java

In today’s digital age, search and highlight text across massive document collections is a common requirement. Whether you’re building a legal review tool, an academic research portal, or a customer‑support dashboard, being able to instantly locate and emphasize key terms dramatically improves usability. In this comprehensive guide, you’ll discover how to implement search and highlight text with GroupDocs.Search for Java—covering both full‑document highlighting and fragment‑level highlighting for focused context.

Quick Answers

  • What does “search and highlight text” mean? It refers to locating query terms in a document and visually emphasizing them (e.g., with background color).
  • Which library provides this capability? GroupDocs.Search for Java.
  • Do I need a license? A free trial works for evaluation; a full license is required for production.
  • Can I customize highlight colors? Yes—any RGB color can be set via HighlightOptions.
  • Is fragment highlighting supported? Absolutely; you can define terms before/after the match to create concise snippets.

What Is Search and Highlight Text?

Search and highlight text is the process of scanning a document index for a given query, retrieving matching documents, and then marking each occurrence of the query term within the document output (HTML, PDF, etc.). This visual cue helps end‑users spot relevant information instantly.

Why Use GroupDocs.Search for Java?

  • High‑performance indexing with configurable compression.
  • Rich highlighting API that works on whole documents and on custom fragments.
  • Cross‑format support (DOCX, PDF, PPTX, TXT, and more).
  • Easy Maven integration and clear Java‑centric API.

Prerequisites

  • Java Development Kit (JDK) 8 or newer.
  • Maven for dependency management.
  • An IDE such as IntelliJ IDEA or Eclipse.
  • Basic familiarity with Java syntax.

Setting Up GroupDocs.Search for Java

Add the GroupDocs repository and dependency to your pom.xml:

<repositories>
   <repository>
      <id>repository.groupdocs.com</id>
      <name>GroupDocs Repository</name>
      <url>https://releases.groupdocs.com/search/java/</url>
   </repository>
</repositories>

<dependencies>
   <dependency>
      <groupId>com.groupdocs</groupId>
      <artifactId>groupdocs-search</artifactId>
      <version>25.4</version>
   </dependency>
</dependencies>

You can also download the latest JAR directly from the official site: GroupDocs.Search for Java releases.

License Acquisition

Start with a free trial or obtain a temporary license for evaluation. For production deployments, purchase a full license to unlock all features.

Implementation Guide

The implementation is split into two practical sections: highlighting in entire documents and highlighting in fragments. Both sections include the essential steps for how to highlight Java documents using GroupDocs.Search.

Configuring Index Settings

Before indexing, configure the storage to use high compression—this reduces disk usage while preserving search speed.

IndexSettings settings = new IndexSettings();
settings.setTextStorageSettings(new TextStorageSettings(Compression.High));

Highlighting in Entire Documents

Step 1: Create and Populate the Index

Create an index folder and add all source files you want to search.

String indexFolder = "/path/to/your/document/directory/HighlightingInEntireDocument";
Index index = new Index(indexFolder, settings);
index.add("/path/to/your/documents");

Step 2: Perform Search and Apply Highlighting

Search for the term (e.g., ipsum) and generate an HTML file with highlighted matches.

SearchResult result = index.search("ipsum");

if (result.getDocumentCount() > 0) {
    FoundDocument document = result.getFoundDocument(0);
    OutputAdapter outputAdapter = new FileOutputAdapter(OutputFormat.Html, "/path/to/your/output/directory/Highlighted.html");
    
    Highlighter highlighter = new DocumentHighlighter(outputAdapter);
    HighlightOptions options = new HighlightOptions();
    options.setHighlightColor(new Color(150, 255, 150)); // Custom green shade
    options.setUseInlineStyles(false); // Prefer CSS for styling
    
    index.highlight(document, highlighter, options);
}

Key options explained

  • Compression – high compression saves storage.
  • HighlightColor – set any RGB value to match your UI palette.
  • UseInlineStyles – false generates clean HTML that can be styled globally with CSS.

Highlighting in Fragments

Step 1: Index and Search (same as above)

String indexFolder = "/path/to/your/document/directory/HighlightingInFragments";
Index index = new Index(indexFolder, settings);
index.add("/path/to/your/documents");

SearchResult result = index.search("ipsum");

Step 2: Define Fragment Context and Highlight

Specify how many terms before and after the match should appear in each fragment.

HighlightOptions options = new HighlightOptions();
options.setTermsBefore(5); // Include 5 terms before the match
options.setTermsAfter(5);   // Include 5 terms after the match
options.setHighlightColor(new Color(127, 200, 255)); // Custom blue shade
options.setUseInlineStyles(true); // Use inline styles for emphasis

FoundDocument document = result.getFoundDocument(0);
FragmentHighlighter highlighter = new FragmentHighlighter(OutputFormat.Html);

index.highlight(document, highlighter, options);

Step 3: Retrieve and Write Highlighted Fragments

Collect the generated fragments and write them to an HTML file.

StringBuilder stringBuilder = new StringBuilder();
FragmentContainer[] fragmentContainers = highlighter.getResult();

for (FragmentContainer container : fragmentContainers) {
    String[] fragments = container.getFragments();
    
    if (fragments.length > 0) {
        stringBuilder.append("\n<br>").append(container.getFieldName()).append("<br>\n");
        
        for (String fragment : fragments) {
            stringBuilder.append(fragment).append("\n");
        }
    }
}

try {
    Files.write(Paths.get("/path/to/your/output/directory/Fragments.html"), stringBuilder.toString().getBytes());
} catch (IOException ex) {
    // Handle exceptions
}

Practical Applications

  1. Legal Document Review – instantly highlight statutes, clauses, or case references.
  2. Academic Research – surface key terminology across dozens of PDFs and Word files.
  3. Customer Support – pinpoint order numbers or error codes within ticket histories.

Performance Considerations

  • Index Size – high compression (Compression.High) reduces disk footprint.
  • Fragment Context – larger termsBefore/After values increase accuracy but may affect speed.
  • Memory Management – monitor JVM heap when indexing large corpora; consider incremental indexing for very large sets.

Common Issues and Solutions

  • Indexing Errors – verify file paths and ensure the application has read/write permissions.
  • No Highlights Appear – confirm that UseInlineStyles matches your output format (HTML vs. PDF).
  • Color Not Applied – make sure the RGB values are within 0‑255 range and that the HTML viewer supports the style.

Frequently Asked Questions

Q: What are the benefits of using GroupDocs.Search for Java?
A: It offers fast, scalable indexing, customizable highlighting, and support for many document formats.

Q: How can I integrate GroupDocs.Search with a REST API?
A: Expose the search and highlight methods via Spring Boot controllers, returning HTML or JSON payloads.

Q: Does the library handle password‑protected files?
A: Yes—provide the password when adding the document to the index.

Q: Can I customize the highlight markup beyond color?
A: Absolutely; you can inject CSS classes via HighlightOptions or modify the HTML after generation.

Q: What version was tested for this guide?
A: The code was validated against GroupDocs.Search 25.4.

Last Updated: 2025-12-26
Tested With: GroupDocs.Search 25.4
Author: GroupDocs