evolve(demo1):dependency injection - constructor injection

spring-demo-1/src/applicationContext.xml

@@ -8,8 +8,16 @@
     http://www.springframework.org/schema/context/spring-context.xsd">
 
     <!-- Define your beans here -->
+
+    <bean id="myFortuneService"
+      class="com.luv2code.springdemo.HappyFortuneService"></bean>
+
     <bean id="myCoach"
       class="com.luv2code.springdemo.TrackCoach">
+
+    		<!-- set up constrcutor injection -->
+    		<constructor-arg ref="myFortuneService"></constructor-arg>
+
     </bean>
 
 </beans>

spring-demo-1/src/com/luv2code/springdemo/BaseballCoach.java

@@ -3,9 +3,22 @@
 
 public class BaseballCoach implements Coach {
 
+	// define a private field for dependency
+	private FortuneService fortuneService;
+
+	// define a constructor for dependency injection
+	public BaseballCoach(FortuneService theFortuneService) {
+		fortuneService = theFortuneService;
+	}
+
 	@Override
 	public String getDailyWorkout() {
 		return "Spend 30 minutes on batting practice";
 	}
 
+	@Override
+	public String getDailyFortune() {
+		return fortuneService.getFortune();
+	}
+
 }

spring-demo-1/src/com/luv2code/springdemo/Coach.java

@@ -4,4 +4,5 @@ public interface Coach {
 
 	public String getDailyWorkout();
 
+	public String getDailyFortune();
 }

spring-demo-1/src/com/luv2code/springdemo/FortuneService.java

@@ -0,0 +1,6 @@
+package com.luv2code.springdemo;
+
+public interface FortuneService {
+
+	public String getFortune();
+}

spring-demo-1/src/com/luv2code/springdemo/HappyFortuneService.java

@@ -0,0 +1,9 @@
+package com.luv2code.springdemo;
+
+public class HappyFortuneService implements FortuneService {
+
+	@Override
+	public String getFortune() {
+		return "This a your lucky day";
+	}
+}

spring-demo-1/src/com/luv2code/springdemo/HelloSpringApp.java

@@ -14,6 +14,7 @@ public static void main(String[] args) {
 
 		// call methods on bean
 		System.out.println(theCoach.getDailyWorkout());
+		System.out.println(theCoach.getDailyFortune());
 
 		// close the context
 		context.close();

spring-demo-1/src/com/luv2code/springdemo/TrackCoach.java

@@ -2,9 +2,25 @@
 
 public class TrackCoach implements Coach {
 
+	private FortuneService fortuneService;
+
+	public TrackCoach() {
+
+	}
+
+	public TrackCoach(FortuneService fortuneService) {
+		super();
+		this.fortuneService = fortuneService;
+	}
+
 	@Override
 	public String getDailyWorkout() {
 		return "Run a hard 5K";
 	}
 
+	@Override
+	public String getDailyFortune() {
+		return "Just do it: " + fortuneService.getFortune();
+	}
+
 }