Search icon CANCEL
Subscription
0
Cart icon
Your Cart (0 item)
Close icon
You have no products in your basket yet
Save more on your purchases! discount-offer-chevron-icon
Savings automatically calculated. No voucher code required.
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Newsletter Hub
Free Learning
Arrow right icon
timer SALE ENDS IN
0 Days
:
00 Hours
:
00 Minutes
:
00 Seconds
Arrow up icon
GO TO TOP
Design Patterns and Best Practices in Java

You're reading from   Design Patterns and Best Practices in Java A comprehensive guide to building smart and reusable code in Java

Arrow left icon
Product type Paperback
Published in Jun 2018
Publisher Packt
ISBN-13 9781786463593
Length 280 pages
Edition 1st Edition
Languages
Arrow right icon
Authors (4):
Arrow left icon
 Singh Singh
Author Profile Icon Singh
Singh
 Puri Puri
Author Profile Icon Puri
Puri
 Ianculescu Ianculescu
Author Profile Icon Ianculescu
Ianculescu
 Torje Torje
Author Profile Icon Torje
Torje
Arrow right icon
View More author details
Toc

Table of Contents (11) Chapters Close

Preface 1. From Object-Oriented to Functional Programming FREE CHAPTER 2. Creational Patterns 3. Behavioral Patterns 4. Structural Patterns 5. Functional Patterns 6. Let's Get Reactive 7. Reactive Design Patterns 8. Trends in Application Architecture 9. Best Practices in Java 10. Other Books You May Enjoy

Error handling


The Observables contain a couple of operators that allow error handling, swallowing exceptions, transforming exceptions, call-finally blocks, retrying the failed sequence, and disposing resources even if an error occurs.

The catch operator

These operators enable recovering from errors by continuing the sequence:

  • onErrorResumeNext: Instructs an Observable to pass control to another Observable given by a supplier, instead of invoking onError when something goes wrong
  • onErrorReturn: Instructs an Observable to emit a default supplied by a function, in case of error
  • onErrorReturnItem: Instructs an Observable to emit a supplied default, in case of error
  • onExceptionResumeNext: Instructs an Observable to pass control to another Observable instead of invoking onError in case something goes wrong

The following example shows how to use the onErrorReturnItem method; calling it without the flatMap trick will stop the flow and output Default at the end. By deferring the call to the exception...

lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime
Visually different images