Main benefits of Collections Framework in Java are as follows:

1. Reusability: Java Collections Framework provides

common classes and utility methods than can be used with

different types of collections. This promotes the reusability

of the code. A developer does not have to re-invent the

wheel by writing the same method again.

2. Quality: Using Java Collection Framework improves the

program quality, since the code is already tested and used

by thousands of developers.

3. Speed: Most of programmers report that their development

speed increased since they can focus on core logic and use

the generic collections provided by Java framework.

4. Maintenance: Since most of the Java Collections

framework code is open source and API documents is

widely available, it is easy to maintain the code written

with the help of Java Collections framework. One

developer can easily pick the code of previous developer.

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