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Open source project

Proj4J

Proj4J is a Java library for coordinate reference system definitions and transformations for geospatial applications.

What this project record adds to its repository

The repository shows the code. This record adds who stands behind the project and which companies build on it, so an agent can judge a dependency, not just find one.

Who maintains it

The owning organization (Eclipse Foundation) as a record of its own, linked to the repository.

What's around it

Related projects (Spatial4j and others) and the articles that mention it, with their sources.

Get this project

The same record, three ways in. No key needed to try it.

MCP

curl -X POST https://mcp.decisioninsights.ai/api/mcp-public \
  -H "content-type: application/json" \
  -H "accept: application/json, text/event-stream" \
  -d '{"id":1,"jsonrpc":"2.0","method":"tools/call","params":{"arguments":{"slug":"proj4j"},"name":"di_get_project"}}'

REST

GET https://api.decisioninsights.ai/api/public/v1/projects/105afbc6-b60c-4541-823e-507834c2e474

CLI

di get-project --slug proj4j

The CLI command and the REST call for this record need a free account: run di login, or send your OAuth token. Over MCP it is free with none.

How an agent can check this project

The check What the record shows Where it is in the data
It's the right project locationtech.github.io/proj4j, not another "Proj4J" codeRepository
Someone stands behind it Maintained under Eclipse Foundation maintainer
View the raw record (JSON-LD)
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