| Which | General environment checking and version finding service. |
| WhichAnt | Get Version information about jakarta-ant. |
| WhichClass | Class finding service. |
| WhichConstant | Simple static constants used throughout org.apache.env package. |
| WhichCrimson | Get Version information about xml-crimson. |
| WhichFactory | Simple factory class for WhichProject implementations. |
| WhichJar | Static worker methods to find version info about jars and classpaths. |
| WhichSaxon | Get Version information about Saxon from http://saxon.sourceforge.net/. |
| WhichXalan | Get Version information about xml-xalan. |
| WhichXerces | Get Version information about xml-xerces. |
| WhichXmlCommons | Get Version information about xml-commons code. |