Add examples

spring-all/src/main/java/org/baeldung/async/AsyncComponent.java

@@ -1,11 +1,11 @@
 package org.baeldung.async;
 
-import java.util.concurrent.Future;
-
 import org.springframework.scheduling.annotation.Async;
 import org.springframework.scheduling.annotation.AsyncResult;
 import org.springframework.stereotype.Component;
 
+import java.util.concurrent.Future;
+
 @Component
 public class AsyncComponent {
 
@@ -19,7 +19,7 @@ public class AsyncComponent {
         System.out.println("Execute method asynchronously " + Thread.currentThread().getName());
         try {
             Thread.sleep(5000);
-            return new AsyncResult<String>("hello world !!!!");
+            return new AsyncResult<>("hello world !!!!");
         } catch (final InterruptedException e) {
 
         }

spring-all/src/main/java/org/baeldung/startup/InitializingBeanExampleBean.java

@@ -1,14 +1,23 @@
 package org.baeldung.startup;
 
+import org.apache.log4j.Logger;
 import org.springframework.beans.factory.InitializingBean;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Scope;
+import org.springframework.core.env.Environment;
 import org.springframework.stereotype.Component;
 
 @Component
 @Scope(value = "prototype")
 public class InitializingBeanExampleBean implements InitializingBean {
 
+    private static final Logger LOG = Logger.getLogger(InitializingBeanExampleBean.class);
+
+    @Autowired
+    private Environment environment;
+
     @Override
     public void afterPropertiesSet() throws Exception {
+        LOG.info(environment);
     }
 }

spring-all/src/main/java/org/baeldung/startup/InvalidInitExampleBean.java

@@ -0,0 +1,18 @@
+package org.baeldung.startup;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.Scope;
+import org.springframework.core.env.Environment;
+import org.springframework.stereotype.Component;
+
+@Component
+@Scope("prototype")
+public class InvalidInitExampleBean {
+
+    @Autowired
+    private Environment environment;
+
+    public InvalidInitExampleBean() {
+        environment.getActiveProfiles();
+    }
+}

spring-all/src/main/java/org/baeldung/startup/LogicInConstructorExampleBean.java

@@ -1,5 +1,6 @@
 package org.baeldung.startup;
 
+import org.apache.log4j.Logger;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Scope;
 import org.springframework.core.env.Environment;
@@ -9,10 +10,14 @@ import org.springframework.stereotype.Component;
 @Scope(value = "prototype")
 public class LogicInConstructorExampleBean {
 
-    @Autowired
+    private static final Logger LOG = Logger.getLogger(LogicInConstructorExampleBean.class);
-    private Environment environment;
 
-    public LogicInConstructorExampleBean() {
+    private final Environment environment;
-        environment.getActiveProfiles();
+
+    @Autowired
+    public LogicInConstructorExampleBean(Environment environment) {
+        this.environment = environment;
+
+        LOG.info(environment);
     }
 }

spring-all/src/main/java/org/baeldung/startup/PostConstructExampleBean.java

@@ -1,17 +1,24 @@
 package org.baeldung.startup;
 
+import org.apache.log4j.Logger;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Scope;
 import org.springframework.core.env.Environment;
 import org.springframework.stereotype.Component;
 
+import javax.annotation.PostConstruct;
+
 @Component
 @Scope(value = "prototype")
 public class PostConstructExampleBean {
 
+    private static final Logger LOG = Logger.getLogger(PostConstructExampleBean.class);
+
     @Autowired
     private Environment environment;
 
-    public PostConstructExampleBean() {
+    @PostConstruct
+    public void init() {
+        LOG.info(environment);
     }
 }

spring-all/src/main/java/org/baeldung/startup/SpringStartupConfig.java

@@ -6,5 +6,4 @@ import org.springframework.context.annotation.Configuration;
 @Configuration
 @ComponentScan("org.baeldung.startup")
 public class SpringStartupConfig {
-
 }

spring-all/src/test/java/org/baeldung/startup/SpringStartupTest.java

@@ -17,9 +17,22 @@ public class SpringStartupTest {
     private ApplicationContext ctx;
 
     @Test(expected = BeanCreationException.class)
-    public void whenInstantiating_shouldThrowNPE() throws Exception {
+    public void whenInstantiating_shouldThrowBCE() throws Exception {
+        ctx.getBean(InvalidInitExampleBean.class);
+    }
+
+    @Test
+    public void whenPostConstruct_shouldLogEnv() throws Exception {
+        ctx.getBean(PostConstructExampleBean.class);
+    }
+
+    @Test
+    public void whenConstructorInjection_shouldLogEnv() throws Exception {
         ctx.getBean(LogicInConstructorExampleBean.class);
     }
 
-
+    @Test
+    public void whenInitializingBean_shouldLogEnv() throws Exception {
+        ctx.getBean(InitializingBeanExampleBean.class);
+    }
 }