EasyExcel is a Java processing library designed for reading and writing XLS, XLSX, and CSV files. It functions as a memory-efficient spreadsheet parser, an object-relational mapper that binds spreadsheet columns to Java class fields, and a stream-based exporter for handling high-volume data.
The library distinguishes itself through a streaming model that processes large files row-by-row via listeners to prevent heap memory overflow. It also operates as a template engine, allowing the population of predefined spreadsheet files with dynamic data while preserving original layouts and styles.
Broad capabilities include automated report generation, data extraction from specific worksheets, and the application of cell styling, merging, and media embedding. The system also supports the direct streaming of spreadsheet data to and from HTTP request and response objects for web-based file transfers.