Code example for field injection and other changes

spring-boot/dependency-injection/src/main/java/com/example/ExampleApplicationCI.java

@@ -1,22 +1,19 @@
 package com.example;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.ApplicationContext;
 
 import com.example.constructorinjection.Cake;
 
-@SpringBootApplication(scanBasePackages= {"com.example.constructorinjection","com.example.dependency"})
-public class ExampleApplicationCI  {
+@SpringBootApplication(scanBasePackages = { "com.example.constructorinjection", "com.example.dependency" })
+public class ExampleApplicationCI {
 
-	private static Logger LOGGER=LoggerFactory.getLogger(ExampleApplicationCI.class);
 	public static void main(String[] args) {
-		
+
 		ApplicationContext context = SpringApplication.run(ExampleApplicationCI.class, args);
 		Cake obj = context.getBean(Cake.class);
-		LOGGER.info("Cake : "+ obj.toString());
+		System.out.println("Cake : " + obj.toString());
 	}
 
 }

spring-boot/dependency-injection/src/main/java/com/example/ExampleApplicationFI.java

@@ -0,0 +1,19 @@
+package com.example;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.context.ApplicationContext;
+
+import com.example.fieldinjection.IceCream;
+
+@SpringBootApplication(scanBasePackages = { "com.example.dependency", "com.example.fieldinjection" })
+public class ExampleApplicationFI {
+
+	public static void main(String[] args) {
+
+		ApplicationContext context = SpringApplication.run(ExampleApplicationSI.class, args);
+		IceCream obj = context.getBean(IceCream.class);
+		System.out.println("IceCream : " + obj.toString());
+	}
+
+}

spring-boot/dependency-injection/src/main/java/com/example/ExampleApplicationSI.java

@@ -1,22 +1,19 @@
 package com.example;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.context.ApplicationContext;
 
-import com.example.setterinjection.Cake;
+import com.example.setterinjection.Cookie;
 
-@SpringBootApplication(scanBasePackages= {"com.example.setterinjection","com.example.dependency"})
-public class ExampleApplicationSI  {
+@SpringBootApplication(scanBasePackages = { "com.example.setterinjection", "com.example.dependency", })
+public class ExampleApplicationSI {
 
-	private static Logger LOGGER=LoggerFactory.getLogger(ExampleApplicationSI.class);
 	public static void main(String[] args) {
-		
+
 		ApplicationContext context = SpringApplication.run(ExampleApplicationSI.class, args);
-		Cake obj = context.getBean(Cake.class);
-		LOGGER.info("Cake : "+ obj.toString());
+		Cookie obj = context.getBean(Cookie.class);
+		System.out.println("Cookie : " + obj.toString());
 	}
 
 }

spring-boot/dependency-injection/src/main/java/com/example/constructorinjection/Cake.java

@@ -1,26 +1,21 @@
 package com.example.constructorinjection;
 
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import java.util.Objects;
+
 import org.springframework.stereotype.Component;
 
 import com.example.dependency.Flavor;
 
-
 @Component
 public class Cake {
 
-	private static Logger LOGGER = LoggerFactory.getLogger(Cake.class);
-
-
 	private Flavor flavor;
 
-	public Cake(Flavor flavor) throws IllegalAccessException {
-		
-		//check if the required dependency is not null
-		if (flavor != null) {
+	Cake(Flavor flavor) {
+
+		// check if the required dependency is not null
+		if (Objects.requireNonNull(flavor) != null) {
 			this.flavor = flavor;
-			LOGGER.info("Flavor from Constructor Injection : " + flavor);
 		} else {
 			throw new IllegalArgumentException("Cake cannot be created with null flavor object");
 		}
@@ -29,10 +24,11 @@ public class Cake {
 	public Flavor getFlavor() {
 		return flavor;
 	}
-	
+
 	@Override
 	public String toString() {
 		return "Cake [flavor=" + flavor + "]";
 	}
 
+
 }

spring-boot/dependency-injection/src/main/java/com/example/constructorinjection/Sandwich.java

@@ -0,0 +1,32 @@
+package com.example.constructorinjection;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import com.example.dependency.Bread;
+import com.example.dependency.Topping;
+
+@Component
+public class Sandwich {
+
+	Topping toppings;
+	Bread breadType;
+
+	Sandwich(Topping toppings) {
+		this.toppings = toppings;
+	}
+
+	@Autowired
+	Sandwich(Topping toppings, Bread breadType) {
+		this.toppings = toppings;
+		this.breadType = breadType;
+	}
+
+	public Topping getToppings() {
+		return toppings;
+	}
+
+	public Bread getBreadType() {
+		return breadType;
+	}
+}

spring-boot/dependency-injection/src/main/java/com/example/dependency/Bread.java

@@ -0,0 +1,17 @@
+package com.example.dependency;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class Bread {
+
+	String breadType;
+
+	public String getBreadType() {
+		return breadType;
+	}
+
+	void setBreadType(String breadType) {
+		this.breadType = breadType;
+	}
+}

spring-boot/dependency-injection/src/main/java/com/example/dependency/Flavor.java

@@ -4,14 +4,14 @@ import org.springframework.stereotype.Component;
 
 @Component
 public class Flavor {
-	
-	String flavorType = " Chocolate ";
-	String color = " White ";
-	
+
+	String flavorType;
+	String color;
+
 	public String getFlavorType() {
 		return flavorType;
 	}
-	
+
 	public String getColor() {
 		return color;
 	}
@@ -20,6 +20,5 @@ public class Flavor {
 	public String toString() {
 		return "Flavor [flavorType=" + flavorType + ", color=" + color + "]";
 	}
-	
 
 }

spring-boot/dependency-injection/src/main/java/com/example/dependency/Pizza.java

@@ -0,0 +1,26 @@
+package com.example.dependency;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+@Component
+public class Pizza {
+
+	@Autowired
+	Topping toppings;
+
+	Pizza(Topping toppings) {
+		this.toppings = toppings;
+	}
+
+	@Autowired
+	public Topping getToppings() {
+		System.out.println("Using field injection - " + this.toppings);
+		return toppings;
+	}
+
+	public void setToppings(Topping toppings) {
+		this.toppings = toppings;
+	}
+
+}

spring-boot/dependency-injection/src/main/java/com/example/dependency/Topping.java

@@ -5,13 +5,13 @@ import org.springframework.stereotype.Component;
 @Component
 public class Topping {
 
-	private String toppingName;
+	String toppingName;
 
 	public String getToppingName() {
 		return toppingName;
 	}
 
-	public void setToppingName(String toppingName) {
+	void setToppingName(String toppingName) {
 		this.toppingName = toppingName;
 	}
 
@@ -20,5 +20,4 @@ public class Topping {
 		return "Topping [toppingName=" + toppingName + "]";
 	}
 
-
 }

spring-boot/dependency-injection/src/main/java/com/example/fieldinjection/IceCream.java

@@ -0,0 +1,27 @@
+package com.example.fieldinjection;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import com.example.dependency.Topping;
+
+@Component
+public class IceCream {
+
+	@Autowired
+	Topping toppings;
+
+	public Topping getToppings() {
+		return toppings;
+	}
+
+	void setToppings(Topping toppings) {
+		this.toppings = toppings;
+	}
+
+	@Override
+	public String toString() {
+		return "IceCream [toppings=" + toppings + "]";
+	}
+
+}

spring-boot/dependency-injection/src/main/java/com/example/setterinjection/Cookie.java

@@ -0,0 +1,27 @@
+package com.example.setterinjection;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import com.example.dependency.Topping;
+
+@Component
+public class Cookie {
+
+	private Topping toppings;
+
+	@Autowired
+	void setTopping(Topping toppings) {
+		this.toppings = toppings;
+	}
+
+	public Topping getTopping() {
+		return toppings;
+	}
+
+	@Override
+	public String toString() {
+		return "Cookie [toppings=" + toppings + "]";
+	}
+
+}

spring-boot/dependency-injection/src/main/resources/application.properties

@@ -1,2 +0,0 @@
-spring.main.web-application-type=none
-spring.main.banner-mode=off

spring-boot/dependency-injection/src/test/java/com/example/test/constructorinjection/TestCakeClassConstructorInjection.java

@@ -3,7 +3,7 @@ package com.example.test.constructorinjection;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.runner.RunWith;
-import org.springframework.beans.factory.annotation.Autowired;
+import org.mockito.InjectMocks;
 import org.springframework.boot.test.context.SpringBootTest;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
@@ -14,12 +14,15 @@ import com.example.constructorinjection.Cake;
 @SpringBootTest(classes = ExampleApplicationCI.class)
 public class TestCakeClassConstructorInjection {
 
-	@Autowired
+//	@Mock
+//	Flavor flavor;
+
+	@InjectMocks
 	Cake cake;
 
 	@Test
 	public void testConstructorInjection() {
-		String testColor = cake.getFlavor().getColor();
-		Assert.assertEquals(testColor, " White ");
+		System.out.println(cake.toString());
+		Assert.assertNotNull(cake.getFlavor());
 	}
 }

spring-boot/dependency-injection/src/test/java/com/example/test/fieldinjection/TestCookieClassFieldInjection.java

@@ -0,0 +1,25 @@
+package com.example.test.fieldinjection;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.InjectMocks;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+import com.example.ExampleApplicationSI;
+import com.example.fieldinjection.IceCream;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringBootTest(classes = ExampleApplicationSI.class)
+public class TestCookieClassFieldInjection {
+
+	@InjectMocks
+	IceCream iceCream;
+
+	@Test
+	public void testSetterInjection() {
+		System.out.println(iceCream.toString());
+		Assert.assertNotNull(iceCream.getToppings());
+	}
+}