35 lines
852 B
Markdown
35 lines
852 B
Markdown
---
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layout: pattern
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title: Lazy Loading
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folder: lazy-loading
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permalink: /patterns/lazy-loading/
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categories: Other
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tags:
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- Java
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- Difficulty-Beginner
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- Idiom
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- Performance
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---
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## Intent
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Lazy loading is a design pattern commonly used to defer
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initialization of an object until the point at which it is needed. It can
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contribute to efficiency in the program's operation if properly and
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appropriately used.
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## Class diagram
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## Applicability
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Use the Lazy Loading idiom when
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* eager loading is expensive or the object to be loaded might not be needed at all
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## Real world examples
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* JPA annotations @OneToOne, @OneToMany, @ManyToOne, @ManyToMany and fetch = FetchType.LAZY
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## Credits
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* [J2EE Design Patterns](http://www.amazon.com/J2EE-Design-Patterns-William-Crawford/dp/0596004273/ref=sr_1_2)
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