Test data can be maintained in external files like Excel to separate data from code. This approach improves maintainability and allows easy updates without modifying the test scripts.

To read Excel files in Java, we use the Apache POI library, which supports both .xls and .xlsx formats.

Typical steps:

• Load the Excel file using FileInputStream to read it as a data stream.
• Create a Workbook instance:
  • XSSFWorkbook for .xlsx files
  • HSSFWorkbook for .xls files
• Access the specific Sheet containing the required data.
• Loop through Row and Cell objects to extract the data.

This allows dynamic data-driven testing without hardcoding values in the test scripts.