apex-lang is an open source Apex library, its Apex port of very popular Apache Common Lang java project. Almost all java developers and open source projects in Java depend on Apache Common Lang. This is really good to see that something similar came to apex in open source. apex-lang is comprising of many Utility classes that port the Apache’s stuff to apex, plus give nice wrapper on top of standard Salesforce apex api also. Here is a list of useful Apex util classes

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