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IOC(Inversion of Control)
: 기존의 프로그래밍에서 개발자가 관리하던 객체의 라이프 사이클(생성, 제어, 소멸 등)을 컨테이너에게 제어권을 위임하는 프로그래밍 기법
: 의존성들을 외부에 정의하고 컨테이너에 의해 공급받음
<BMICalculator.java>
package DI02;
public class BMICalculator {
private double lowWeight;
private double normal;
private double overWeight;
private double obesity;
public void bmicalculation(double weight, double height) {
double h = height * 0.01;
double result = weight / (h*h);
System.out.println("BMI 지수: "+(int)result);
if(result > obesity) {
System.out.println("비만.");
}else if(result > overWeight) {
System.out.println("과체중.");
}else if(result > normal) {
System.out.println("정상.");
}else {
System.out.println("저체중.");
}
}
public void setLowWeight(double lowWeight) {
this.lowWeight = lowWeight;
}
public void setNormal(double normal) {
this.normal = normal;
}
public void setOverWeight(double overWeight) {
this.overWeight = overWeight;
}
public void setObesity(double obesity) {
this.obesity = obesity;
}
}
<MyInfo.java>
package DI02;
import java.util.ArrayList;
public class MyInfo {
private String name;
private double height;
private double weight;
private ArrayList<String> hobbies;
private BMICalculator bmiCalculator;
public void bmiCalculation() {
bmiCalculator.bmicalculation(weight, height);
}
public void getInfo() {
System.out.println("이름: "+name);
System.out.println("키: "+height);
System.out.println("몸무게: "+weight);
System.out.println("취미: "+hobbies);
bmiCalculation();
}
public void setName(String name) {
this.name = name;
}
public void setHeight(double height) {
this.height = height;
}
public void setWeight(double weight) {
this.weight = weight;
}
public void setHobbies(ArrayList<String> hobbies) {
this.hobbies = hobbies;
}
public void setBmiCalculator(BMICalculator bmiCalculator) {
this.bmiCalculator = bmiCalculator;
}
}
<MainClass.java>
package DI02;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
public class MainClass {
public static void main(String[] args) {
String configLocation = "classpath:applicationCTX2.xml";
AbstractApplicationContext ctx = new GenericXmlApplicationContext(configLocation);
MyInfo myInfo = ctx.getBean("myInfo", MyInfo.class);
myInfo.getInfo();
ctx.close();
}
}
<applicationCTX2.xml>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="bmiCalculator" class="DI02.BMICalculator">
<property name="lowWeight" value="18.5"/>
<property name="normal" value="23"/>
<property name="overWeight" value="25"/>
<property name="obesity" value="30"/>
</bean>
<bean id="myInfo" class="DI02.MyInfo">
<property name=" value="김춘추"/>
<property name="height" value="170"/>
<property name="weight" value="72"/>
<property name="hobbies">
<list>
<value>말타기</value>
<value>활쏘기</value>
</list>
</property>
<property name="bmiCalculator>
<ref bean="bmiCalculator"/>
</property>
</bean>
</beans>
<결과>
김춘추
키: 170.0
몸무게: 72.0
취미: [말타기, 활쏘기]
BMI 지수: 24
정상
<Student.java>
package DI03;
public class Student {
private String name;
private int age;
private String gradeNum;
private String classNum;
public Student(String name, int age, String gradeNum, String classNum) {
super();
this.name = name;
this.age = age;
this.gradeNum = gradeNum;
this.classNum = classNum;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getGradeNum() {
return gradeNum;
}
public void setGradeNum(String gradeNum) {
this.gradeNum = gradeNum;
}
public String getClassNum() {
return classNum;
}
public void setClassNum(String classNum) {
this.classNum = classNum;
}
}
<StudentInfo.java>
package DI03;
public class StudentInfo {
private Student student;
public StudentInfo(Student student) {
this.student = student;
}
public void getStudentInfo() {
if(student!=null) {
System.out.println("이름: "+student.getName());
System.out.println("나이: "+student.getAge());
System.out.println("학년: "+student.getGradeNum());
System.out.println("반 : "+student.getClassNum());
System.out.println("==================");
}
}
public Student getStudent() {
return student;
}
public void setStudent(Student student) {
this.student = student;
}
}
<MainClass.java>
package DI03;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
public class MainClass {
public static void main(String[] args) {
String configLocation = "classpath:applicationCTX3.xml";
AbstractApplicationContext ctx = new GenericXmlApplicationContext(configLocation);
StudentInfo studentInfo = ctx.getBean("studentInfo", StudentInfo.class);
studentInfo.getStudentInfo();
Student student2 = ctx.getBean("student2", Student.class);
studentInfo.setStudent(student2);
studentInfo.getStudentInfo();
System.out.println("student2.getAge()-->"+student2.getAge());
System.out.println(student2.getAge()+5);
ctx.close();
Student student3 = new Student("김유신", 30, "3학년", "11번");
System.out.println("student3.getAge()-->"+student3.getAge());
}
}
<applicationCTX3.xml>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="student1" class="DI03.Student">
<constructor-arg value="연개소문"/>
<constructor-arg value="50"/>
<constructor-arg value="4학년"/>
<constructor-arg value="25번"/>
</bean>
<bean id="student2" class="DI03.Student">
<constructor-arg value="양만춘"/>
<constructor-arg value="38"/>
<constructor-arg value="3학년"/>
<constructor-arg value="11번"/>
</bean>
<bean id="studentInfo" class="DI03.StudentInfo">
<constructor-arg>
<ref bean="student1"/>
</constructor-arg>
</bean>
</beans>
<결과>
이름: 연아들
나이: 50
학년: 4학년
반 : 25번
==================
이름: 양만춘
나이: 38
학년: 3학년
반 : 11번
==================
student2.getAge()-->38
43
student3.getAge()-->30
<CollectionBean.java>
package DI04;
import java.util.Map;
public class CollectionBean {
private Map<String, String> addressList;
public Map<String, String> getAddressList() {
return addressList;
}
public void setAddressList(Map<String, String> addressList) {
this.addressList = addressList;
}
}
<MainClass.java>
package DI04;
import java.util.Map;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
public class MainClass {
public static void main(String[] args) {
String configLocation = "classpath:applicationCTX4.xml";
AbstractApplicationContext ac = new GenericXmlApplicationContext(configLocation);
CollectionBean collectionBean = ac.getBean("collectionBean", CollectionBean.class);
Map<String, String> addressList = (Map<String,String>)collectionBean.getAddressList();
System.out.println("홍길동 주소 :"+addressList.get("홍길동"));
System.out.println("중앙 주소 :"+addressList.get("중앙"));
}
}
<applicationCTX4.xml>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="collectionBean" class="DI04.CollectionBean">
<property name="addressList">
<map>
<entry>
<key><value>홍길동</value></key><value>율도국</value>
</entry>
<entry>
<key><value>중앙</value></key><value>강남</value>
</entry>
</map>
</property>
</bean>
</beans>
<결과>
홍길동 주소 :율도국
중앙 주소 :강남
<Student.java>
package DI07;
import java.util.ArrayList;
public class Student {
private String name;
private int age;
private ArrayList<String> hobbies;
private double weight;
private double height;
public Student(String name, int age, ArrayList<String> hobbies) {
this.name = name;
this.age = age;
this.hobbies = hobbies;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public ArrayList<String> getHobbies() {
return hobbies;
}
public void setHobbies(ArrayList<String> hobbies) {
this.hobbies = hobbies;
}
public double getWeight() {
return weight;
}
public void setWeight(double weight) {
this.weight = weight;
}
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
}
<ApplicationConfig.java>
package DI07;
import java.util.ArrayList;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class ApplicationConfig {
@Bean
public Student student1() {
ArrayList<String> hobbies = new ArrayList<String>();
hobbies.add("팝뮤직");
hobbies.add("피아노");
Student student = new Student("안예은", 27, hobbies);
student.setHeight(160);
student.setWeight(50);
return student;
}
@Bean
public Student student2() {
ArrayList<String> hobbies = new ArrayList<String>();
hobbies.add("뮤지컬");
hobbies.add("음악감상");
Student student = new Student("김준수", 35, hobbies);
student.setHeight(178);
student.setWeight(70);
return student;
}
}
<MainClass.java>
package DI07;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
public class MainClass {
public static void main(String[] args) {
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ApplicationConfig.class);
Student student1 = ctx.getBean("student1",Student.class);
System.out.println("이름: "+student1.getName());
System.out.println("나이: "+student1.getAge());
System.out.println("취미: "+student1.getHobbies());
System.out.println("신장: "+student1.getHeight());
System.out.println("몸무게: "+student1.getWeight());
Student student2 = ctx.getBean("student2",Student.class);
System.out.println("이름: "+student2.getName());
System.out.println("나이: "+student2.getAge());
System.out.println("취미: "+student2.getHobbies());
System.out.println("신장: "+student2.getHeight());
System.out.println("몸무게: "+student2.getWeight());
}
}
<결과>
이름: 안예은
나이: 27
취미: [팝뮤직, 피아노]
신장: 160.0
몸무게: 50.0
이름: 김준수
나이: 35
취미: [뮤지컬, 음악감상]
신장: 178.0
몸무게: 70.0
<Student>
package DI08;
import java.util.ArrayList;
public class Student {
private String name;
private int age;
private ArrayList<String> hobbies;
private double weight;
private double height;
public Student(String name, int age, ArrayList<String> hobbies) {
this.name = name;
this.age = age;
this.hobbies = hobbies;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public ArrayList<String> getHobbies() {
return hobbies;
}
public void setHobbies(ArrayList<String> hobbies) {
this.hobbies = hobbies;
}
public double getWeight() {
return weight;
}
public void setWeight(double weight) {
this.weight = weight;
}
public double getHeight() {
return height;
}
public void setHeight(double height) {
this.height = height;
}
}
<ApplicationConfig.java>
package DI08;
import java.util.ArrayList;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
public class ApplicationConfig {
@Bean
public Student student1() {
ArrayList<String> hobbies = new ArrayList<String>();
hobbies.add("수영");
hobbies.add("물내리기");
Student student = new Student("을지문덕", 55, hobbies);
student.setHeight(170);
student.setWeight(70);
return student;
}
}
<MainClass.java>
package DI08;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
import DI08.Student;
public class MainClass {
public static void main(String[] args) {
AbstractApplicationContext ctx = new GenericXmlApplicationContext("classpath:applicationCTX8.xml");
Student student1 = ctx.getBean("student1",Student.class);
System.out.println("이름: "+student1.getName());
System.out.println("나이: "+student1.getAge());
System.out.println("취미: "+student1.getHobbies());
System.out.println("신장: "+student1.getHeight());
System.out.println("몸무게: "+student1.getWeight());
Student student2 = ctx.getBean("student2",Student.class);
System.out.println("이름: "+student2.getName());
System.out.println("나이: "+student2.getAge());
System.out.println("취미: "+student2.getHobbies());
System.out.println("신장: "+student2.getHeight());
System.out.println("몸무게: "+student2.getWeight());
ctx.close();
}
}
<applicationCTX8.xml>
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd">
//context로 Annotation과 xml 환경설정 연결
<context:annotation-config></context:annotation-config>
<bean class="DI08.ApplicationConfig"></bean>
<bean id="student2" class="DI08.Student">
<constructor-arg value="양만춘"/>
<constructor-arg value="30"/>
<constructor-arg>
<list>
<value>활쏘기</value>
<value>안시성</value>
</list>
</constructor-arg>
<property name="height" value="175"/>
<property name="weight" value="70"/>
</bean>
</beans>
<결과>
이름: 을지문덕
나이: 55
취미: [수영, 물내리기]
신장: 170.0
몸무게: 70.0
이름: 양만춘
나이: 30
취미: [활쏘기, 안시성]
신장: 175.0
몸무게: 70.0
xml과 Annotation 각각의 특징
xml은 AbstractApplicationContext ctx = new GenericXmlApplicationContext("classpath:");를 사용하고,
Annotation은 @Configuration과 @Bean을 설정해 준 후
AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(클래스명.class);를 사용하여 연결해준다.
xml과 annotation을 혼합 사용 시에는 xml파일에서 <context:annotaion-config/>를 작성해 annotation연결을 수행한다.
DI 종류 중 setter와 constructor 각각의 장점
--Setter Injection
--Constructor Injection