This is the official Java driver for Factual's API:

Driver Documentation

• Getting Started
• Debugging and Support

Querying Factual Data

• Query Filters
• Field Selection
• Row Filters
• Geo Filters
• Paging: Limit and Offset
• Sorting Results

Other APIs

• Crosswalk API
• Match API and Resolve API
• Monetize API
• Geopulse

Supporting Calls & Services

• Facets Call
• Schema Call
• Geocoding

Using Specific Datasets

• World Geographies
• Global Products
• Products Crosswalk

Writing to Factual

• Submit and Insert
  
• Clear
  
• Flag an Entity
  

Other Items & Miscellany

• Raw Requests
• Multi Queries
• Diffs
• Set Request Timeout

API Documentation

• Factual REST API Documentation
• Factual Support