Spring--IOC（一）

第一节：spring ioc简介
IOC（控制反转：Inverse of Control ） ，又称作 依赖注入，是一种重要的面向对象编程的法则来削减计算机程序
的耦合问题，也是轻量级的 Spring 框架的核心。

一些对象与其之间的依赖关系

public class ZhangSan implements Tester{

    public void test(){
        System.out.println("张三-测试程序");
    }
}


public class Lisi implements Tester{

    public void test(){
        System.out.println("李四-测试程序");
    }
}


public interface Tester {

    public void test();
}

public class JavaWork {
    
    private Tester tester;
    
    public void setTester(Tester tester) {
        this.tester = tester;
    }

    public void doTest(){
        /*ZhangSan zhangsan=new ZhangSan();
        zhangsan.test();*/
        tester.test(); //如果测试人员换成lisi就要改代码，改为使用接口方式，降低对象之间的耦合度
    }
}

使用普通方式的业务执行代码与使用spring控制对象的代码，beans.xml 使用反射机制来创建对象。

public class Test {

    /**
     * 主管执行命令
     * @param args
     */
    public static void main(String[] args) {
        JavaWork javaWork=new JavaWork();
        // javaWork.setTester(new ZhangSan());
        javaWork.setTester(new Lisi());
        javaWork.doTest();
    }
}


public class Test2 {

    public static void main(String[] args) {
        ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
        JavaWork javaWork=(JavaWork)ac.getBean("javaWork");
        javaWork.doTest();
    }
}

<?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="zhangsan" class="com.java1234.service.ZhangSan"></bean>
    
    <bean id="lisi" class="com.java1234.service.Lisi"></bean>
    
    <bean id="javaWork" class="com.java1234.service.JavaWork">
    <!-- 给JavaWork类中的属性tester注入对象 ，ref对应bean id-->
        <property name="tester" ref="lisi"></property>
    </bean>
  
</beans>

 第三节：装配一个 bean
第四节：依赖注入
1，属性注入；
2，构造函数注入；(通过类型；通过索引；联合使用,不常用)
3，工厂方法注入；(非静态工厂，静态工厂)
4，泛型依赖注入；(Spring4 整合 Hibernate4 的时候顺带讲), 参考：http://jinnianshilongnian.iteye.com/blog/1989330

例子用到的类

public class People {

    private int id;
    private String name;
    private int age;
    
    
    
    public People() {
        super();
        // TODO Auto-generated constructor stub
    }
    
    
    
    
    public People(int id, String name, int age) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
    }




    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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;
    }


    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age + "]";
    }

    
    
}


public class PeopleFactory {

    public People createPeople(){
        People p=new People();
        p.setId(5);
        p.setName("小七");
        p.setAge(77);
        return p;
    }
}



public class PeopleFactory2 {

    public static People createPeople(){
        People p=new People();
        p.setId(8);
        p.setName("小八");
        p.setAge(88);
        return p;
    }
}




public class Test2 {

    public static void main(String[] args) {
        ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml");
        People people=(People)ac.getBean("people");
        System.out.println(people);
        
        // 属性注入
        People people2=(People)ac.getBean("people2");
        System.out.println(people2);
        
        // 构造方法注入
        People people3=(People)ac.getBean("people3");
        System.out.println(people3);
        
        People people4=(People)ac.getBean("people4");
        System.out.println(people4);
        
        People people5=(People)ac.getBean("people5");
        System.out.println(people5);
        
        // 工厂方法注入
        People people7=(People)ac.getBean("people7");
        System.out.println(people7);
        
        People people8=(People)ac.getBean("people8");
        System.out.println(people8);
    }
}

在xml配置文件中注入

<?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">

    <!-- 装配一个 bean -->
    <bean id="people" class="com.java1234.entity.People"></bean>
    
    <!-- 依赖注入,1，属性注入； -->
    <bean id="people2" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
    </bean>
    <!-- 2，构造函数注入；(通过类型；通过索引；联合使用) -->
    <bean id="people3" class="com.java1234.entity.People">
        <constructor-arg type="int" value="2"></constructor-arg>
        <constructor-arg type="String" value="李四"></constructor-arg>
        <constructor-arg type="int" value="22"></constructor-arg>
    </bean>
    
    <bean id="people4" class="com.java1234.entity.People">
        <constructor-arg index="0" value="3"></constructor-arg>
        <constructor-arg index="1" value="王五"></constructor-arg>
        <constructor-arg index="2" value="55"></constructor-arg>
    </bean>
    
    <bean id="people5" class="com.java1234.entity.People">
        <constructor-arg index="0" type="int" value="4"></constructor-arg>
        <constructor-arg index="1" type="String" value="招六"></constructor-arg>
        <constructor-arg index="2" type="int" value="66"></constructor-arg>
    </bean>
    <!-- 3，工厂方法注入；(非静态工厂，需要定义一个工厂bean) -->
    <bean id="peopleFactory" class="com.java1234.factory.PeopleFactory"></bean>
    
    <bean id="people7" factory-bean="peopleFactory" factory-method="createPeople"></bean>
  <!-- 静态工厂,不需要定义工厂bean,直接用类名.方法 -->
      <bean id="people8" class="com.java1234.factory.PeopleFactory2" factory-method="createPeople"></bean>
</beans>

 第五节：注入参数
1，基本类型值；
2，注入 bean；
3，内部 bean；
4，null 值；
5，级联属性；
6，集合类型属性；

public class Dog {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    
    
}


public class People {

    private int id;
    private String name;
    private int age;
    private Dog dog ;
    private List<String> hobbies=new ArrayList<String>();
    private Set<String> loves=new HashSet<String>();
    private Map<String,String> works=new HashMap<String,String>();
    private Properties addresses=new Properties();
    
    public People() {
        super();
        // TODO Auto-generated constructor stub
    }
    
    
    
    
    public People(int id, String name, int age) {
        super();
        this.id = id;
        this.name = name;
        this.age = age;
    }

    
    

    public Set<String> getLoves() {
        return loves;
    }




    public void setLoves(Set<String> loves) {
        this.loves = loves;
    }




    public List<String> getHobbies() {
        return hobbies;
    }




    public void setHobbies(List<String> hobbies) {
        this.hobbies = hobbies;
    }

    


    public Map<String, String> getWorks() {
        return works;
    }




    public void setWorks(Map<String, String> works) {
        this.works = works;
    }

    


    public Properties getAddresses() {
        return addresses;
    }




    public void setAddresses(Properties addresses) {
        this.addresses = addresses;
    }




    public Dog getDog() {
        return dog;
    }




    public void setDog(Dog dog) {
        this.dog = dog;
    }




    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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;
    }




    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age
                + ", dog=" + dog + ", hobbies=" + hobbies + ", loves=" + loves
                + ", works=" + works + ", addresses=" + addresses + "]";
    }

}



public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    // 基本类型值
    @Test
    public void test1() {
        People people=(People)ac.getBean("people1");
        System.out.println(people);
    }
    
    // 注入bean
    @Test
    public void test2() {
        People people=(People)ac.getBean("people2");
        System.out.println(people);
    }
    
    
    // 内部bean
    @Test
    public void test3() {
        People people=(People)ac.getBean("people3");
        System.out.println(people);
    }
    
    // 注入null
    @Test
    public void test4() {
        People people=(People)ac.getBean("people4");
        System.out.println(people);
    }
    
    // 级联属性
    @Test
    public void test5() {
        People people=(People)ac.getBean("people5");
        System.out.println(people);
    }
    
    // 注入集合
    @Test
    public void test6() {
        People people=(People)ac.getBean("people6");
        System.out.println(people);
    }
}

<?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="people1" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
    </bean>
    
    <!-- 注入bean -->
    <bean id="dog1" class="com.java1234.entity.Dog">
        <property name="name" value="Jack"></property>
    </bean>
    
    <bean id="people2" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <property name="dog" ref="dog1"></property>
    </bean>
    
    <!-- 内部bean -->
    <bean id="people3" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <property name="dog">
            <bean class="com.java1234.entity.Dog">
                <property name="name" value="Tom"></property>
            </bean>
        </property>
    </bean>
    
    <!-- 注入null -->
    <bean id="people4" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <property name="dog">
            <null></null>
        </property>
    </bean>
    
    <!-- 级联属性  需要在People类中创建对象dog=new Dog(),否则会报错-->
<!--      <bean id="people5" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <property name="dog.name" value="Jack2"></property>
    </bean>   -->
    
    <!-- 注入集合 -->
    <bean id="people6" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <property name="dog" ref="dog1"></property>
        <property name="hobbies">
            <list>
                <value>唱歌</value>
                <value>跳舞</value>
            </list>
        </property>
        <property name="loves">
            <set>
                <value>唱歌2</value>
                <value>跳舞2</value>
            </set>
        </property>
        <property name="works">
            <map>
                <entry>
                    <key><value>上午</value></key>
                    <value>写代码</value>
                </entry>
                <entry>
                    <key><value>下午</value></key>
                    <value>测试代码</value>
                </entry>
            </map>
        </property>
        <property name="addresses">
            <props>
                <prop key="address1">aaaaa</prop>
                <prop key="address2">bbbbb</prop>
            </props>
        </property>
    </bean>  
    
</beans>

第六节：Spring 自动装配
通过配置 default-autowire 属性，Spring IOC 容器可以自动为程序注入 bean；默认是 no，不启用自动装配；
default-autowire 的类型有 byName,byType,constructor；
byName：通过名称进行自动匹配；
byType：根据类型进行自动匹配；
constructor：和 byType 类似，只不过它是根据构造方法注入而言的，根据类型，自动注入；
建议：自动装配机制慎用，它屏蔽了装配细节，容易产生潜在的错误；

  default-autowire="constructor"  这里面配置各种装配方式

<?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"
        default-autowire="constructor">

    <!-- constructor：和 byType 类似，只不过它是根据构造方法注入而言的，根据类型，自动注入；People类中需要有个Dog的构造方法 -->
    <bean id="dog2" class="com.java1234.entity.Dog">
        <property name="name" value="Jack"></property>
    </bean>
    
    <!-- byName：通过名称进行自动匹配； bean id 和 People类中的属性名dog相同-->
    <!-- <bean id="dog" class="com.java1234.entity.Dog">
        <property name="name" value="Tom"></property>
    </bean> -->
    
    
    <bean id="people1" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
    
    </bean>
    
</beans>

public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    @Test
    public void test1() {
        People people=(People)ac.getBean("people1");
        System.out.println(people);
    }
    
}


package com.java1234.entity;


public class People {

    private int id;
    private String name;
    private int age;
    private Dog dog;
    
    
    
    public People() {
        super();
        // TODO Auto-generated constructor stub
    }
    
    
    public People(Dog dog) {
        super();
        System.out.println("constructor");
        this.dog = dog;
    }


    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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 Dog getDog() {
        return dog;
    }
    public void setDog(Dog dog) {
        this.dog = dog;
    }
    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age
                + ", dog=" + dog.getName() + "]";
    }
    
}



public class Dog {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    
    
}

第七节：方法注入
Spring bean 作用域默认是 单例 singleton； 可以通过配置 prototype ，实现多例；
方法注入 lookup-method

<?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">

    <!-- 单例 singleton； 多例 prototype ，测试 -->
    <bean id="dog" class="com.java1234.entity.Dog" scope="prototype">
        <property name="name" value="Jack"></property>
    </bean>
    
    
    
    <bean id="people1" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <!-- spring 通过cglib封装的，dog 都是单例 -->
        <!--  <property name="dog" ref="dog"></property>  -->
        <!-- People中的getDog改成抽象方法，通过spring动态注入 ，dog设置为prototype时每次都是新创建的，了解一下-->
        <lookup-method name="getDog" bean="dog"/>
    </bean>
    
</beans>

public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    @Test
    public void test1() {
        People people=(People)ac.getBean("people1");
        People people2=(People)ac.getBean("people1");
        //内部bean都是单例，除非采用方法注入
        System.out.println(people.getDog()==people2.getDog());
        
        //单例，多例测试
        System.out.println(ac.getBean("dog")==ac.getBean("dog"));
    }
    

}

public abstract class People {

    private int id;
    private String name;
    private int age;
    private Dog dog;
    
    
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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 abstract Dog getDog();
    
/*    public Dog getDog(){
        return dog;
    }*/
    public void setDog(Dog dog) {
        this.dog = dog;
    }
    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age
                + ", dog=" + dog.getName() + "]";
    }
    

}



public class Dog {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    
    
}

第八节：方法替换

<?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="people1" class="com.java1234.entity.People">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
        <property name="age" value="11"></property>
        <!-- 调用people1中的getDog 时就会调用people2中的reimplement替换方法 -->
        <replaced-method name="getDog" replacer="people2"></replaced-method>
    </bean>
    <!-- People2实现接口MethodReplacer，重写替换方法 -->
    <bean id="people2" class="com.java1234.entity.People2"></bean>
</beans>

public class People2 implements MethodReplacer {

    @Override
    public Object reimplement(Object arg0, Method arg1, Object[] arg2)
            throws Throwable {
        Dog dog=new Dog();
        dog.setName("Tom");
        return dog;
    }
    

}

public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    @Test
    public void test1() {
        People people=(People)ac.getBean("people1");
        System.out.println(people.getDog().getName());
    }
    

}

public class People {

    private int id;
    private String name;
    private int age;
    private Dog dog;
    
    
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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 Dog getDog() {
        Dog dog=new Dog();
        dog.setName("Jack");
        return dog;
    }
    public void setDog(Dog dog) {
        this.dog = dog;
    }
    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age
                + ", dog=" + dog.getName() + "]";
    }
    

}

public class Dog {

    private String name;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
    
    
}

第九节：bean之间的关系
1，继承；
2，依赖；
3，引用；

<?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="dog" class="com.java1234.entity.Dog">
        <property name="name" value="jack"></property>
    </bean>
    <!-- 定义一个父类，有公共属性 -->
    <bean id="abstractPeople" class="com.java1234.entity.People" abstract="true">
        <property name="className" value="高三5班"></property>
        <property name="age" value="19"></property>
    </bean>
    <!-- 子类继承父类的属性，也可以重写 -->
    <!-- 依赖关系 depends-on="autority" 先加载autority这个bean -->
    <bean id="zhangsan" parent="abstractPeople" depends-on="autority">
        <property name="id" value="1"></property>
        <property name="name" value="张三"></property>
    </bean>
    
    <bean id="lisi" parent="abstractPeople">
        <property name="id" value="2"></property>
        <property name="name" value="李四"></property>
        <property name="age" value="20"></property>
        <property name="dog" ref="dog"></property>    <!-- bean 之间的引用关系ref="" -->
    </bean>
    
    
    <bean id="autority" class="com.java1234.service.Authority"></bean>

public class T {

    private ApplicationContext ac;

    @Before
    public void setUp() throws Exception {
        ac=new ClassPathXmlApplicationContext("beans.xml");
    }

    @Test
    public void test1() {
        People zhangsan=(People)ac.getBean("zhangsan");
        System.out.println(zhangsan);
        
        People lisi=(People)ac.getBean("lisi");
        System.out.println(lisi);
    }
    

}


public class Authority {

    public Authority() {
        System.out.println("获取权限");
    }

    
}


public class People {

    private int id;
    private String name;
    private int age;
    private String className;
    private Dog dog;
    
    
    public People() {
        System.out.println("初始化People");
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    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 getClassName() {
        return className;
    }
    public void setClassName(String className) {
        this.className = className;
    }
    
    
    public Dog getDog() {
        return dog;
    }
    public void setDog(Dog dog) {
        this.dog = dog;
    }
    @Override
    public String toString() {
        return "People [id=" + id + ", name=" + name + ", age=" + age
                + ", className=" + className + ", dog=" + dog + "]";
    }


}

第十节：bean作用范围
1，singleton Spring ioc 容器中仅有一个 Bean实例，Bean 以单例的方式存在；
2，prototype 每次从容器中调用 Bean时，都返回一个新的实例；
3，request 每次 HTTP 请求都会创建一个新的 Bean； （前面2个重点，后面几个了解）
4，session 同一个 HTTP Session 共享一个 Bean；
5，global session 同一个全局 Session 共享一个 Bean，一般用于 Portlet 应用环境；
6，application 同一个 Application 共享一个 Bean；