• Provide "free" (as in "free speech" and "free beer"), fast, lightweight implementations of the java.util Collections API. These implementations are designed to be pluggable replacements for their JDK equivalents.
• Whenever possible, provide the same collections support for primitive types. This gap in the JDK is often addressed by using the "wrapper" classes (java.lang.Integer, java.lang.Float, etc.) with Object-based collections. For most applications, however, collections which store primitives directly will require less space and yield significant performance gains.

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