Spring @Primary annotation

In this post under Spring Core, I will explain with example the purpose of “@Primary” annotation. When doing autowiring by type, there may be scenarios where two bean definitions can be considered for injection. For example if we have below DAO class package package26; public class Dao { private String daoName; public Dao(String daoName) {…… Continue reading Spring @Primary annotation

Autowiring Optional beans

In this post under Spring Core, I will show with example how to use Java’s Optional class to declare a bean (to be injected) as optional. In one of my previous post under Spring Core, I showed you about “required” attribute in “@Autowired” annotation. For recap, “@Autowired” annotation has only one attribute named “required” whose…… Continue reading Autowiring Optional beans

Autowiring a collection and array of beans

In this post under Spring Core, I will explain with example how to autowire a collection and array of beans. For our example I will use the below “Dao” class Dao class package package22; public class Dao { private String daoName; public Dao(String daoName) { this.daoName = daoName; } @Override public String toString() { return…… Continue reading Autowiring a collection and array of beans

“required” attribute of @Autowired annotation

In this post under Spring Core, I will explain with example the purpose of “required” attribute of “@Autowired” annotation. When we tell Spring framework to wire two beans say “Bean2” to “Bean1” as shown below package package20;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Component;@Componentpublic class Bean1 { @Autowired private Bean2 bean2; public Bean2 getBean2() { return bean2; } public void…… Continue reading “required” attribute of @Autowired annotation

Example of @Autowired (setter injection approach 2)

In this post under Spring Core, I will show another approach of achieving setter injection using “@Autowired” annotation. In my previous posts, I showed with example how to achieve setter injection by applying “@Autowired” annotation at field level. In this post I will show how to achieve setter injection by applying “@Autowired” annotation directly on…… Continue reading Example of @Autowired (setter injection approach 2)

Example of @Autowired (constructor injection)

In this post under Spring Core, I will show with example, how to use “@Autowired” annotation for constructor injection. In previous post, I showed how to use “@Autowired” annotation for setter injection. We call an approach as setter injection, when Spring framework automatically inject dependency to an object by calling the setter method of the…… Continue reading Example of @Autowired (constructor injection)

Example of @Autowired (setter injection approach 1)

In this post under Spring Core, I will explain with example the purpose and how to use “@Autowired” annotation. Till now in all my previous posts, you have seen how to create a bean. We can create a bean using either “@Bean” or “@Component” annotation. I have also showed you how to wire one “@Bean”…… Continue reading Example of @Autowired (setter injection approach 1)

Using @Profile on @Component annotated beans

In the previous post under Spring Core, I showed how to use “@Profile” annotation with “@Configuration” and “@Bean” annotation. In this post under Spring Core, I will show with example how to use “@Profile” annotation with “@Component” annotation. In previous post I also mentioned that “@Profile” annotation can be used with “@Configuration”, “@Bean”, and “@Component”…… Continue reading Using @Profile on @Component annotated beans