Merge pull request #7323 from rozagerardo/rozagerardo/BAEL-10914_Create-spring-mvc-basics-from-spring-mvc-java

[BAEL-10914] create spring mvc basics from spring mvc java - part 2

spring-core/README.md

@@ -24,3 +24,4 @@
 - [What is a Spring Bean?](https://www.baeldung.com/spring-bean)
 - [Spring PostConstruct and PreDestroy Annotations](https://www.baeldung.com/spring-postconstruct-predestroy)
 - [Guice vs Spring – Dependency Injection](https://www.baeldung.com/guice-spring-dependency-injection)
+- [Circular Dependencies in Spring](http://www.baeldung.com/circular-dependencies-in-spring)

spring-core/src/main/java/com/baeldung/circulardependency/CircularDependencyA.java

@@ -0,0 +1,29 @@
+package com.baeldung.circulardependency;
+
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.InitializingBean;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.ApplicationContextAware;
+import org.springframework.stereotype.Component;
+
+@Component
+public class CircularDependencyA implements ApplicationContextAware, InitializingBean {
+
+	private CircularDependencyB circB;
+
+	private ApplicationContext context;
+
+	public CircularDependencyB getCircB() {
+		return circB;
+	}
+
+	@Override
+	public void afterPropertiesSet() throws Exception {
+		circB = context.getBean(CircularDependencyB.class);
+	}
+
+	@Override
+	public void setApplicationContext(final ApplicationContext ctx) throws BeansException {
+		context = ctx;
+	}
+}

spring-core/src/main/java/com/baeldung/circulardependency/CircularDependencyB.java

@@ -0,0 +1,22 @@
+package com.baeldung.circulardependency;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+@Component
+public class CircularDependencyB {
+
+	private CircularDependencyA circA;
+
+	private String message = "Hi!";
+
+	@Autowired
+	public void setCircA(final CircularDependencyA circA) {
+		this.circA = circA;
+	}
+
+	public String getMessage() {
+		return message;
+	}
+
+}

spring-core/src/test/java/com/baeldung/circulardependency/CircularDependencyIntegrationTest.java

@@ -0,0 +1,35 @@
+package com.baeldung.circulardependency;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = { TestConfig.class })
+public class CircularDependencyIntegrationTest {
+
+    @Autowired
+    ApplicationContext context;
+
+    @Bean
+    public CircularDependencyA getCircularDependencyA() {
+        return new CircularDependencyA();
+    }
+
+    @Bean
+    public CircularDependencyB getCircularDependencyB() {
+        return new CircularDependencyB();
+    }
+
+    @Test
+    public void givenCircularDependency_whenSetterInjection_thenItWorks() {
+        final CircularDependencyA circA = context.getBean(CircularDependencyA.class);
+
+        Assert.assertEquals("Hi!", circA.getCircB().getMessage());
+    }
+}

spring-core/src/test/java/com/baeldung/circulardependency/TestConfig.java

@@ -0,0 +1,10 @@
+package com.baeldung.circulardependency;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan(basePackages = { "com.baeldung.circulardependency" })
+public class TestConfig {
+
+}