How to use org.apache.commons.lang namespace in Java?

Question

I tried in Eclipse to use org.apache.commons.lang.NotImplementedException, though it seems from what I can see both from IntelliSense and the Package Explorer, that that namespace does not exist. So I guess I must load some other package(do you call them libraries in java?) than those it loaded by default.

This is my current setup:

Answer 1

You need to add Apache commons jar file to the project. You can select the jar you want from here - http://commons.apache.org/downloads/index.html
for lang you need this - commons-lang-2.5.jar

Answer 2

Download the commons lang library and add it to your eclipse project library.

To add the jar to your eclipse project library:

1. open project properties
2. choose Java Build Path
3. tab to Libraries
4. add jars (if the jar is inside your project folder)
5. add external jar (if the jar is outside your project folder)