[Spring学习笔记 2 ]装配各种类型的属性 map,list,array,null,properties

一.spring Ioc容器补充(1)
Spring Ioc容器 DI(依赖注入):
注入的方式：设值方法注入setter(属性注入)/构造子注入（构造函数传入依赖的对象)/字段注入field（注解）/接口注入out
装配的方式:手动装配<property>，<constructor-arg>,@Autowired,@Resource/自动装配

1.装配各种类型的属性：
A、简单属性value属性或者value元素

      <bean id="person" class="com.lspring.step2.Person">
    <property name="name" value="liyy"></property>
    <!-- property元素中的内容叫属性值，会自动把value描述的值转换成对应属性的类型 -->
    <property name="age" >
    <value>30</value>
    </property>
    <property name="tel"><value>ABCD</value></property>
    <!-- 也可以使用value装配一些Spring支持的类型 -->
    <property name="homePage"><value>http://google.com</value></property>
    </bean>

B、引用其它bean,使用ref属性或者ref标签
 <!--ref引用其它的bean,local表示引用本容器中的bean,parent表示引用父容器中的某个bean,bean表示先在当前容器中找，找不到再到父容器中找 -->
        <property name="parent">
            <ref bean="person_c"></ref>
        </property>

C、使用内部bean

    <property name="parent">
            <bean class="com.lspring.step2.Person">
                <constructor-arg value="Jerry"></constructor-arg>
                <constructor-arg>
                    <value>33</value>
                </constructor-arg>
            </bean>
        </property>

D、使用集合/装配集合
1).数组
代码：
    private String[] favs;
    
    public String[] getFavs() {
        return favs;
    }

    public void setFavs(String[] favs) {
        this.favs = favs;
    }    

xml配置：
<!-- 装配数组 -->
        <property name="favs">
            <array>
                <value>足球</value>
                <value>篮球</value>
                <value>排球</value>
            </array>
        </property>

2).装配list
    private List<String> school;
    
    
    public List<String> getSchool() {
        return school;
    }

    public void setSchool(List<String> school) {
        this.school = school;
    }


    <!-- 装配list集合 -->
        <property name="school">
            <list>
                <value>中华第一小学</value>
                <value>中华第一高中</value>
                <value>中华第一大学</value>
            </list>
        </property>


3).装配set 不接受重复的值，只显示一条重复的传下
    private Set<String> cities;
    
    public Set<String> getCities() {
        return cities;
    }

    public void setCities(Set<String> cities) {
        this.cities = cities;
    }
    <property name="cities">
            <set>
                <value>shanghai</value>
                <value>shanghai</value>
                <value>shanghai</value>
            </set>
        </property>    

E.装配Map

    private Map<String, Double> scores; 

    public Map<String, Double> getScores() {
        return scores;
    }

    public void setScores(Map<String, Double> scores) {
        this.scores = scores;
    }
<!-- 装配Map -->
        <property name="scores">
        <map>
            <entry key="语文" value="50"></entry>
            <entry key="外文" value="30"></entry>
            <!-- 也可以使用key-ref,和value-ref来指向其他的bean -->        
        </map>
        </property>

F.装配properties 
private Properties properties;
    
    public Properties getProperties() {
        return properties;
    }

    public void setProperties(Properties properties) {
        this.properties = properties;
    }

        <!-- 装配属性类型 -->
        <!-- <property name="properties"> <props> <prop key="qq">1213343</prop> 
            <prop key="msn">kkk@qqq.com</prop> </props> </property> -->
        <!-- 在value中直接使用值对作为属性内容 -->
        <property name="properties">
            <value>
                qq=133234
                msn=1312@dfjk.com
            </value>
        </property>

G.装配空值
    private Integer age=25;
    默认给age赋初值
    
    <bean id="person_null" class="com.lspring.step2.Person">
        <property name="name" value="小哥李"></property>
        <property name="age">
        <!-- 使用nul标签来指定空值。 -->
        <null></null>
        </property>
    </bean>

 

 

代码如下：Person.java PersonDao.java

package com.lspring.step2;

import java.net.URL;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
import java.util.Vector;

public class Person {
    private String name;
    private Integer age=25;
    private String tel;
    private Person parent;
    private String[] favs;
    private List<String> school = new Vector();
    private Set<String> cities;
    private Properties properties;
    
    public Properties getProperties() {
        return properties;
    }

    public void setProperties(Properties properties) {
        this.properties = properties;
    }

    private Map<String, Double> scores; 

    public Map<String, Double> getScores() {
        return scores;
    }

    public void setScores(Map<String, Double> scores) {
        this.scores = scores;
    }

    public Set<String> getCities() {
        return cities;
    }

    public void setCities(Set<String> cities) {
        this.cities = cities;
    }

    public List<String> getSchool() {
        return school;
    }

    public void setSchool(List<String> school) {
        this.school = school;
    }

    public String[] getFavs() {
        return favs;
    }

    public void setFavs(String[] favs) {
        this.favs = favs;
    }

    private URL homePage;

    public URL getHomePage() {
        return homePage;
    }

    public void setHomePage(URL homePage) {
        this.homePage = homePage;
    }

    public String getName() {
        return name;
    }

    public Person(String name, Integer age) {
        super();
        this.name = name;
        this.age = age;
    }

    public Person() {
        super();
        System.out.println("初始化person!");
    }

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

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public String getTel() {
        return tel;
    }

    public void setTel(String tel) {
        this.tel = tel;
    }

    public Person getParent() {
        return parent;
    }

    public void setParent(Person parent) {
        this.parent = parent;
    }

    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + ", tel=" + tel + ", parent=" + parent + ", favs=" + Arrays.toString(favs) + ", school=" + school + ", cities=" + cities + ", properties=" + properties + ", scores=" + scores + ", homePage=" + homePage + "]";
    }
}

package com.lspring.step2;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class PersonDao {
	@Test
	public void injectTest(){
		@SuppressWarnings("resource")
		ApplicationContext applicationContext = new ClassPathXmlApplicationContext("beans_step2.xml");
		System.out.println(applicationContext.getBean("person"));
		System.out.println(applicationContext.getBean("person_c"));
		Person person = (Person) applicationContext.getBean("person");
		//Spring 会把集合类型，初始化时统一使用某种类型
		System.out.println(person.getSchool().getClass());
		System.out.println("person_null:"+applicationContext.getBean("person_null"));
	}
	
}

　　xml文件如下：beans_step2.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-3.2.xsd">
    <bean id="person_c" class="com.lspring.step2.Person">
        <constructor-arg>
            <value>Tom</value>
        </constructor-arg>
        <constructor-arg value="22"></constructor-arg>
        <property name="parent">
            <bean class="com.lspring.step2.Person">
                <constructor-arg value="Jerry"></constructor-arg>
                <constructor-arg>
                    <value>33</value>
                </constructor-arg>
            </bean>
        </property>
    </bean>

    <bean id="person" class="com.lspring.step2.Person">
        <property name="name" value="liyy"></property>
        <!-- property元素中的内容叫属性值，会自动把value描述的值转换成对应属性的类型 -->
        <property name="age">
            <value>30</value>
        </property>
        <property name="tel">
            <value>ABCD</value>
        </property>
        <!-- 也可以使用value装配一些Spring支持的类型 -->
        <property name="homePage">
            <value>http://google.com</value>
        </property>
        <!-- 1. <property name="parent" ref="person_c"></property>=2. <property 
            name="parent"><ref bean="person_c"/></property> -->
        <!--ref引用其它的bean,local表示引用本容器中的bean,parent表示引用父容器中的某个bean,bean表示先在当前容器中找，找不到再到父容器中找 -->
        <property name="parent">
            <ref bean="person_c"></ref>
        </property>
        <!-- 装配数组 -->
        <property name="favs">
            <array>
                <value>足球</value>
                <value>篮球</value>
                <value>排球</value>
            </array>
        </property>
        <!-- 装配list集合 -->
        <property name="school">
            <list>
                <value>中华第一小学</value>
                <value>中华第一高中</value>
                <value>中华第一大学</value>
            </list>
        </property>
        <!-- 装配set集合 -->
        <property name="cities">
            <set>
                <value>shanghai</value>
                <value>shanghai</value>
                <value>shanghai</value>
            </set>
        </property>
        <!-- 装配Map -->
        <property name="scores">
            <map>
                <entry key="语文" value="50"></entry>
                <entry key="外文" value="30"></entry>
                <!-- 也可以使用key-ref,和value-ref来指向其他的bean -->
            </map>
        </property>
        <!-- 装配属性类型 -->
        <!-- <property name="properties"> <props> <prop key="qq">1213343</prop> 
            <prop key="msn">kkk@qqq.com</prop> </props> </property> -->
        <!-- 在value中直接使用值对作为属性内容 -->
        <property name="properties">
            <value>
                qq=133234
                msn=1312@dfjk.com
            </value>
        </property>
    </bean>
    <bean id="person_null" class="com.lspring.step2.Person">
        <property name="name" value="小哥李"></property>
        <property name="age">
            <!-- 使用nul标签来指定空值。 -->
            <null></null>
        </property>
    </bean>
</beans>