SpringOne Platform 2017 Arjen Poutsma, Pivotal In Spring Framework 5.0, we introduced a new, functional web framework, next to the existing annotation-driven programming model. In this talk, we will discuss this new framework: how it is used, what its goals are, how it compares to the annotation model, and other related topics.

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New in Spring Framework 5.0:
Functional Web Framework
By Arjen Poutsma
@poutsma

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I do like annotations...
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...but there are downsides
• “Magic”
• No link between data and behavior
• Reflection
• Performance
• Type Erasure
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4. Unless otherwise indicated, these slides are © 2013-2016 Pivotal Software, Inc. and licensed under a
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Functional Web Framework: Design Goals
• Functional Style
• java.util.function
• java.util.stream
• More library; less framework
• Explicit
• Customizable
• No reflection
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Functional Style – Immutability
• No change after construction
• Builders
• Thread-safety
• e.g. String
• toUpperCase()
• StringBuilder
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Functional Style - First Class Functions
• Functions as first-class citizens
• Functions as arguments
• Functions as return value
• Reusability
• e.g. String
• indexOf(char) vs indexOf(Predicate<Char>)
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Functional Style - Pure Functions
• Same result given same arguments
• No side effects
• Limit side effects
• Application boundaries
• Testability
• Cacheability
• Parallelization
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Where does this fit in?
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9. Unless otherwise indicated, these slides are © 2013-2016 Pivotal Software, Inc. and licensed under a
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Demo
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Q&A
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