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Java 9 Dependency Injection
book

Java 9 Dependency Injection

by Nilang Patel, Krunal Patel
April 2018
Intermediate to advanced content levelIntermediate to advanced
246 pages
6h 11m
English
Packt Publishing
Content preview from Java 9 Dependency Injection

Optional injection

Guice provides a way to declare an injection as optional. The method and field might be optional, which causes Guice to quietly overlook them when the dependencies aren't accessible. Optional injection can be used by mentioning the @Inject(optional=true) annotation:

public class AppConsumer {  private static final String DEFAULT_MSG = "Hello";  private string message = DEFAULT_MSG;    @Inject(optional=true)  public void setDefaultMessage(@Named("SMS") String message) {    this.message = message;  }}
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Publisher Resources

ISBN: 9781788296250Supplemental Content