Java Excel Libraries

Polars is a high-performance columnar data processing library designed for efficient analytical workflows. It functions as a structured data library that organizes information into typed columns, utilizing the Apache Arrow memory format to enable zero-copy data sharing and cache-friendly, vectorized operations. The engine is built to handle large-scale tabular datasets, providing both local and distributed analytical runtimes that scale from single-machine environments to multi-node clusters. The project distinguishes itself through a sophisticated lazy query engine that constructs abstract e

EPPlus is a .NET library designed for programmatically creating, manipulating, and styling Excel files using the Open XML format. It functions as an office file manipulator and spreadsheet processor that allows for the generation and modification of workbooks without requiring the local installation of office productivity software. The library enables the creation of complex workbooks featuring charts, pivot tables, and conditional formatting for automated reporting. It includes an internal calculation engine to execute embedded formulas and spreadsheet logic, and provides security features s

SheetJS is a comprehensive library for parsing, manipulating, and generating complex spreadsheet file formats. It functions as a universal data processor that maps diverse binary, XML, and text-based file structures into a unified internal object model, allowing developers to create, read, and transform workbook data programmatically. The library distinguishes itself through a portable logic layer that provides a consistent execution environment across web browsers, server-side runtimes, and native desktop or mobile applications. By utilizing stream-based processing, it handles large files in

This project is an educational resource and a collection of instructional materials for performing data manipulation and statistical analysis using Python. It provides a comprehensive set of guides and code examples for using the Pandas, NumPy, and Matplotlib libraries to analyze structured data. The resource includes a dedicated guide for reshaping, cleaning, and aggregating tabular data and time series via Pandas, alongside a reference for high-performance vectorized operations and linear algebra using NumPy. It also features tutorials for creating publication-quality charts, distribution p

Pandas is a high-performance data analysis library that provides a comprehensive framework for manipulating, cleaning, and transforming structured datasets. It centers on labeled one-dimensional and two-dimensional data structures, allowing users to construct, filter, and reshape tabular information while performing complex arithmetic and logical operations. The library distinguishes itself through a sophisticated indexing engine that enables automatic data alignment during calculations and relational merges. By utilizing a block-based memory layout, it optimizes cache locality for vectorized

This is a Laravel Excel integration library used for importing and exporting spreadsheet files within the Laravel framework. It functions as both a spreadsheet data exporter for converting database queries and collections into files and a spreadsheet data importer for mapping workbook data to database models. The library includes an HTML to spreadsheet converter that transforms HTML table templates into downloadable documents to preserve specific layout designs. It supports large dataset exports via background queuing and processes bulk data imports through chunked reading and batch inserts.

Day.js is a lightweight utility for parsing, validating, and manipulating date objects. It provides a fluent, chainable interface that allows for complex time calculations and transformations to be performed through a sequence of readable method calls. By utilizing an immutable wrapper pattern, the library ensures data integrity by creating new instances for every operation rather than modifying existing objects. The project is distinguished by a minimalist core abstraction that maintains a small footprint by offloading non-essential features to an optional, modular plugin system. This archit

xlwings - Make Excel fly with Python!

This library is a header-only C++ framework designed for the serialization, parsing, and manipulation of structured data. It provides a recursive variant data model that represents arbitrary structures as native types, allowing developers to navigate, modify, and patch hierarchical data using standard pointer paths and declarative update patterns. The project distinguishes itself through its template-based architecture, which enables type-safe data structures and custom type mapping at compile time. It offers a unified interface for binary format abstraction, supporting multiple compact repre

Webhook.site is a web-based tool that captures, inspects, and debugs incoming HTTP requests and emails sent to a unique URL, without requiring any server setup. It also functions as an API mocking and response modification tool, capable of generating mock APIs from OpenAPI specifications and altering HTTP responses, headers, and status codes for testing purposes. Beyond inspection, it serves as a platform for webhook automation and workflow orchestration, triggering multi-step automations—including database queries, SSH commands, and HTTP calls—when a webhook is received. The service distingu

Gson is a Java library designed for the serialization and deserialization of objects into structured text formats. It functions as a reflection-based data mapper, inspecting class structures at runtime to automatically convert memory-resident objects into data representations and reconstruct them back into typed language objects. The library distinguishes itself through a modular type-adapter pattern that allows for custom conversion rules for complex or nested structures. It also provides robust support for production environments by generating build-time metadata and configuration rules, wh

smartTable is a data grid component and table view framework for Android. It functions as an annotation-driven UI library that uses class and field markers to automatically map data models to visual columns and define table properties. The project distinguishes itself through deep spreadsheet integration, providing tools to import and export data to and from Excel files while preserving cell formatting, styles, colors, and alignment. It also features a canvas-based rendering system that supports complex grid layouts with merged cells, frozen headers, and column locking. The library covers a

vue-admin-template is a boilerplate for building administrative interfaces using Vue.js. It provides a pre-configured layout, routing, and state management to bootstrap admin dashboards. The project includes a role-based access control system to restrict menu visibility and route access based on user permissions. It features a component scaffolding tool for generating boilerplate views and business components from templates, as well as an automated SVG icon management system for registering and rendering vector graphics. The template covers data management through Excel import and export uti

DuckDB is an in-process analytical database engine designed to run directly within an application process. As a zero-dependency, embedded system, it provides enterprise-grade SQL data processing capabilities without the overhead of managing a dedicated database server. It is built to handle complex analytical and aggregation tasks by storing and retrieving information in columns, allowing for high-performance relational data manipulation. The engine distinguishes itself through a columnar vectorized execution model that maximizes CPU cache efficiency during query operations. It employs adapti

This project is a Model Context Protocol server that enables artificial intelligence assistants to interact directly with Microsoft Excel files. It functions as a bridge, allowing external systems to read, write, and modify spreadsheet data through a standardized interface. By supporting both direct file manipulation and headless application automation, the server provides a comprehensive utility for programmatic workbook management. The server distinguishes itself by combining data processing capabilities with a visual rendering pipeline. It can generate image snapshots of specific spreadshe

OpenBB is a financial data platform and investment research terminal designed to aggregate, normalize, and distribute market data across analytical workflows. It functions as a comprehensive ecosystem that bridges disparate financial data providers with custom applications, spreadsheets, and internal modeling infrastructure. The platform distinguishes itself through a provider-based data abstraction layer that normalizes heterogeneous financial APIs into a consistent, schema-driven format. This architecture supports quantitative research automation and the construction of interactive, widget-

PHPExcel is a PHP spreadsheet library used for programmatically reading and writing spreadsheet files in various formats. It utilizes an in-memory spreadsheet model that maps spreadsheet structures to a hierarchy of objects for programmatic manipulation. The library functions as an Office Open XML processor for generating and manipulating XLSX documents and serves as a reader for extracting data and structure from legacy binary XLS files. It also includes tools for CSV data integration and importing. The project provides capabilities for automated report generation and spreadsheet data extra

Actual is a local-first personal finance manager designed to help users track income, manage expenses, and maintain a balanced budget. It functions as a data-centric application that prioritizes offline access and local file storage, ensuring that financial records remain available and performant regardless of network connectivity. The platform distinguishes itself through a robust architectural foundation that emphasizes data integrity and auditability. Every financial action is recorded as an immutable sequence of events, and all currency values are processed using an integer-based arithmet

This project is an AI agent orchestration platform that provides a visual environment for building, testing, and deploying complex automation workflows. It functions as a low-code development interface where users can chain discrete functional blocks into dependency-aware pipelines to integrate artificial intelligence with external data and services. The platform supports the creation of intelligent conversational agents, automated business processes, and multi-service API orchestrations within a unified workspace. The platform distinguishes itself through its event-driven integration engine,

jsPDF is a document creation engine designed to generate professional PDF files through a unified programming interface. It functions as a cross-platform graphics library that enables the programmatic assembly of data into structured layouts, supporting both client-side generation within web browsers and server-side rendering in backend environments. The library utilizes a canvas-based drawing API that translates high-level geometric and text instructions into standardized PDF vector primitives. By employing a cross-platform runtime abstraction, it decouples document generation logic from env

This project is a curated library of Python code examples, educational resources, and programming tutorials. It functions as an educational repository designed to teach Python language fundamentals through practical implementation tasks, real-world exercises, and functional code snippets. The collection covers a diverse range of implementation examples, including the development of interactive websites and message boards using web frameworks. It also features scripts for audio speech processing, automated media processing for images, and the extraction of data from web content. Additional ca

VeighNa is an event-driven, modular platform designed for the development, backtesting, and execution of automated financial trading strategies. It provides a comprehensive suite of tools that includes a centralized trading terminal for monitoring portfolios and market conditions, alongside a robust algorithmic trading engine that manages real-time data processing and order execution. The platform distinguishes itself through a highly decoupled architecture that isolates algorithmic logic from market connectivity, allowing for independent strategy development and testing. It utilizes a dynami

XlsxWriter is a library for generating spreadsheets in the XLSX format, functioning as an Excel workbook writer and file generator. It provides the capability to write data, apply cell formatting, and build complex layouts across multiple worksheets. The project distinguishes itself with a memory-optimized writing mode that flushes large datasets to disk row-by-row, enabling the creation of files exceeding 4 GB while minimizing RAM consumption. It also includes a specialized mechanism for embedding binary project files and digital signatures to enable VBA macros and signed scripts within work

This project is a comprehensive, community-driven directory of software resources, libraries, and frameworks for the Java programming language. It serves as a centralized knowledge base designed to help developers discover tools and industry-standard solutions for building and maintaining software applications. The repository distinguishes itself through a hierarchical taxonomy that organizes a vast array of technical components into a structured, navigable tree. By relying on distributed peer contributions, the index remains a living resource that reflects current community-recommended pract

This project is a collection of Python scripts and tools designed for web scraping, browser automation, and large-scale data extraction. It provides a set of implementations for retrieving information from websites and private APIs, including tools for multimedia downloading and social media data archiving. The toolset includes specialized mechanisms for bypassing anti-scraping measures through IP proxy pool rotation and multi-threaded crawlers. It also features capabilities for simulating browser sessions to handle authentication, intercepting session cookies, and decrypting network payloads

This project is a command-line processor designed for the parsing, filtering, and transformation of structured data streams. It functions as a declarative programming environment that treats data as immutable streams, allowing users to perform complex structural modifications through the composition of small, reusable functions. By utilizing a recursive tree traversal engine, the system enables the navigation, inspection, and modification of deeply nested hierarchical data structures. The engine distinguishes itself through a stream-oriented architecture that processes input records one by on

ClosedXML is an open-source .NET spreadsheet library and wrapper used for reading and writing Excel files. It provides an object-oriented interface for manipulating workbook structures and cell data within .xlsx and .xlsm files using the OpenXML standard. The library abstracts the complexity of the OpenXML SDK, allowing developers to generate and modify spreadsheets programmatically without requiring Microsoft Office to be installed on the system. It covers a range of spreadsheet management capabilities, including workbook generation, file loading, and data extraction. The toolset supports p

FlatBuffers is a cross-platform serialization library designed for performance-critical applications that require efficient, zero-copy data access. By organizing data in a structured binary format, it allows applications to read and write complex data structures directly from memory-mapped buffers without the need for intermediate parsing or temporary object allocation. The project distinguishes itself through a schema-driven approach that balances high-performance access with long-term data evolution. It utilizes a unique memory layout featuring relative offsets and inline fixed-size structu

This project is a Model Context Protocol server that provides an interface for AI agents to programmatically create, read, and modify Excel workbooks. It serves as a bridge that enables large language models to perform spreadsheet automation and data visualization. The server allows AI agents to generate native Excel charts and pivot tables from raw data, transforming structured information into visual summaries. It provides a mechanism for remote spreadsheet management through a protocol-based connectivity layer. The system covers a broad range of spreadsheet manipulation capabilities, incl

This project is an algorithmic trading engine designed for the automated execution of cryptocurrency strategies. It provides a modular execution core that connects to multiple centralized and decentralized exchanges, allowing users to deploy rule-based trading logic across various spot and futures markets. The platform serves as a comprehensive environment for the entire trading lifecycle, from initial strategy development to live market operations. What distinguishes this platform is its integrated suite for quantitative analysis and predictive modeling. It features a robust backtesting engi

Apache Fesod is a lightweight Java library that wraps Apache POI to provide a streaming API for reading and writing large Excel files. Its core identity is a low-memory spreadsheet processor that prevents out-of-memory errors by handling data row by row, never loading an entire document into memory at once. The library distinguishes itself through a listener-driven event model that fires row-level events to user code as each row is parsed, enabling incremental processing. It also includes an object mapping layer that maps spreadsheet rows directly to Java objects using configurable column map

WeChatMsg is a database forensic parser and local data processor designed to extract and reconstruct structured message data from raw binary files. By operating entirely on the host machine, the tool ensures data sovereignty and privacy, performing all decryption and transformation tasks without requiring network access or external dependencies. The project distinguishes itself through a static analysis-based extraction method that reconstructs message threads by matching unique identifiers and timestamps across fragmented database tables. Its decoupled architecture separates low-level binary

Laravel-Excel is an integration library for importing and exporting spreadsheet data between Laravel applications and Excel or CSV files. It provides a suite of tools for bidirectional spreadsheet integration, including a system for reading workbooks and mapping data into database models. The library distinguishes itself through a background processing system that handles large imports and exports using chunking and job queues. It supports template-driven exports by converting HTML tables from view templates into spreadsheet cells. The toolset covers broad capabilities for large dataset proc

ImHex is a professional-grade hex editor and binary data analysis platform designed for inspecting, modifying, and reverse engineering raw file contents. It functions as a schema-driven engine that interprets complex binary structures by applying custom definitions to map and visualize byte-level data. The platform distinguishes itself through a dedicated domain-specific language that allows users to define structural schemas for automated file parsing. This capability is supported by a dynamic plugin architecture and an event-driven registry, which enable the integration of external modules

Handsontable is a JavaScript data grid that provides a spreadsheet-like interface for managing and editing large datasets within web applications. It functions as a virtualized data table that renders only visible cells to maintain performance, paired with a synchronization layer that binds the grid to underlying data structures. The project distinguishes itself through a built-in spreadsheet calculation engine for evaluating mathematical and logical expressions and a dedicated tool for exporting grid content into Excel XLSX files. It ensures interoperability with external spreadsheet softwar

Chart.js is a declarative data visualization framework that renders interactive, responsive charts directly onto an HTML5 canvas element. It functions as a configuration-driven engine, transforming structured datasets into complex graphical representations by merging user-defined settings with global defaults. The library utilizes a high-performance rendering pipeline that executes drawing commands during each animation frame to maintain smooth visual feedback. The project distinguishes itself through a modular, extensible architecture that allows developers to register custom scales, control

Pandoc is a universal document converter that translates content between a wide range of markup and binary formats. It functions by parsing input documents into a unified intermediate abstract syntax tree, which serves as the foundation for consistent manipulation and transformation across diverse output types. The system is distinguished by its modular reader-writer pipeline, which decouples input parsing from output generation to allow for granular control over document structure. Users can programmatically manipulate this intermediate tree through a robust filter system, supporting both ex

PhpSpreadsheet is a PHP library used for reading and writing spreadsheet files across various formats. It functions as a spreadsheet file generator and an Excel file parser, allowing for the programmatic creation and manipulation of documents compatible with software such as Microsoft Excel and LibreOffice Calc. The library provides capabilities for programmatic spreadsheet generation and data extraction, enabling the conversion of data from spreadsheet files into programmable PHP formats. It also facilitates cross-format spreadsheet conversion, allowing data to be moved between different sta

D3 is a modular library providing low-level primitives for creating data-driven visualizations. It functions as a flexible framework that allows for direct control over visual presentation by mapping abstract data dimensions to graphical properties, such as position, color, and size, without imposing predefined chart abstractions. The library distinguishes itself by offering specialized tools for complex data representation, including algorithmic layouts for hierarchical structures and geographic projection utilities for mapping spherical coordinates. It also includes a comprehensive suite fo

Docling is a modular framework designed for document parsing, layout analysis, and structured data extraction. It transforms unstructured files and web content into a unified, hierarchical data model that preserves the spatial and semantic relationships between text, tables, images, and layout elements. By normalizing diverse input formats into a consistent internal representation, the library enables uniform processing across various document types. The project distinguishes itself through a schema-driven approach that maps document regions to strongly-typed objects, ensuring data accuracy t

Vue-typescript-admin-template is a TypeScript-based admin panel starter built with Vue CLI 3, providing a complete foundation for building enterprise back-office interfaces. It enforces type safety across Vue components using TypeScript, reducing runtime errors and improving code maintainability, while offering a dynamic route permission system that controls sidebar navigation and page access by mapping user roles to route permissions at runtime. The template includes a mock API service layer that simulates backend responses for frontend development without a live server, along with internati

This project is a comprehensive platform for quantitative investment research, machine learning, and algorithmic trading. It provides an end-to-end environment for developing, testing, and executing financial strategies, supporting the entire lifecycle from data ingestion and feature engineering to model training and backtesting. The system is distinguished by its configuration-driven workflow orchestration, which allows researchers to automate complex pipelines and manage experiments through declarative files. It features a high-performance data infrastructure that utilizes custom binary for

ExcelDataReader is a C# library used to extract data and metadata from Microsoft Excel spreadsheets and CSV files. It functions as a workbook parser that converts spreadsheet content into structured data sets for programmatic access and iteration. The project includes a specialized metadata extractor for retrieving cell-level details, such as number formats, styles, row heights, column widths, and merged cell ranges. It also provides a stream processor for parsing plain text CSV files with customizable encoding and separator detection. The library supports the OpenXML standard for modern spr

This project is an algorithmic trading platform designed to automate financial market analysis and the execution of investment strategies. It provides an end-to-end environment for processing real-time market data through automated decision models, allowing for the triggering of financial transactions based on predefined quantitative signals and risk parameters without manual intervention. The platform distinguishes itself through a modular pipeline architecture that decouples data ingestion, signal generation, and trade execution, facilitating the iterative refinement of investment models. I

Kotaemon is an orchestration framework designed for building modular, agentic workflows that integrate document processing, retrieval-augmented generation, and multi-step reasoning. It provides a comprehensive platform for developing document-based question answering systems, allowing users to chain language models, prompt templates, and external tools into complex, automated pipelines. The system distinguishes itself through a highly modular architecture that emphasizes component-based composition and schema-driven data exchange. It supports autonomous agents capable of decomposing complex q

This project is an uncompromising, deterministic code formatter for Python. It functions by parsing source code into an abstract syntax tree and regenerating it according to a rigid, opinionated set of style rules. By automating the formatting process, it eliminates manual style debates and configuration overhead, ensuring that code remains consistent across entire projects regardless of the original input. The tool distinguishes itself through its focus on speed and seamless integration into development workflows. It utilizes content-based file caching and parallel processing to maintain hig

This project serves as a comprehensive language ecosystem index, functioning as a centralized, community-curated directory for the Go programming language. It organizes a vast landscape of software components, libraries, and development tools into a structured, navigable hierarchy, enabling developers to efficiently discover resources tailored to specific functional domains. The repository distinguishes itself through a decentralized contribution model, where community-driven updates ensure the index remains current with the rapidly evolving software landscape. Beyond simple resource listing,