java / beginner
Snippet
Constructor-based Dependency Injection
Constructor injection is the recommended way to handle dependencies. It ensures that required fields are final and the bean is fully initialized upon creation.
snippet.java
java
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@Componentpublic class NotificationManager {private final EmailService emailService;public NotificationManager(EmailService emailService) {this.emailService = emailService;}}
spring
Breakdown
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private final EmailService emailService;
Declares an immutable dependency.
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public NotificationManager(EmailService emailService)
Spring automatically finds and injects the required bean through the constructor.