Spring-注入参数详解-[集合类型属性]

小小工匠
发布于 2021-08-16 16:28:00
3920
发布于 2021-08-16 16:28:00
文章被收录于专栏：小工匠聊架构
概述

java.util包中的集合类型是最常用的结构数据类型，主要包括List、Set、Map、Properties。
Spring为这些集合类型属性提供了专属的配置标签
常用集合

代码已托管到Github—> https://github.com/yangshangwei/SpringMaster
Set

实例

POJO类
package com.xgj.ioc.inject.construct.jihe.set;

import java.util.Iterator;
import java.util.Set;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取注入的set,遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {
        Set set = pets.getSet();
        Iterator it = set.iterator();
        while (it.hasNext()) {
            System.out.println("PetShop has " + it.next());
        }
    }
}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.set;

import java.util.HashSet;
import java.util.Set;

public class Pets {

    private Set set = new HashSet();

    public Set getSet() {
        return set;
    }

    public void setSet(Set set) {
        this.set = set;
    }

}
 
配置文件 

<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="pets" class="com.xgj.ioc.inject.construct.jihe.set.Pets">
        <property name="set">
            <set>
                <value>bearvalue>
                <value>dogvalue>
                <value>catvalue>
                <value>snakevalue>
                <value>pigvalue>
            set>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.set.PetShop">
        <property name="pets" ref="pets"/>
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.set;

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

public class InjectSetTest {
    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/set/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果 
 
 
List 
List属性既可以通过注入字符串，也可以通过注入容器中其他的Bean 
 
实例 
POJO类 
package com.xgj.ioc.inject.construct.jihe.list;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取容器注入的List，遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {
        for (int i = 0; i < pets.getPetsList().size(); i++) {
            System.out.println("PetShop has " + pets.getPetsList().get(i));
        }
    }

}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.list;

import java.util.ArrayList;
import java.util.List;

public class Pets {

    private List petsList = new ArrayList();

    public List getPetsList() {
        return petsList;
    }

    public void setPetsList(List petsList) {
        this.petsList = petsList;
    }

}
 
配置文件 

<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="pets" class="com.xgj.ioc.inject.construct.jihe.list.Pets">
        <property name="petsList">
            <list>
                <value>dogvalue>
                <value>catvalue>
                <value>bearvalue>
                <value>rabbitvalue>
                <value>birdvalue>
            list>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.list.PetShop">
        <property name="pets">
            <ref bean="pets"/>
        property>
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.list;

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

public class InjectListTest {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/list/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果 
 
假设一个属性类型可以通过字符串字面值进行配置，那么该类型对应的数组类型的属性比入String[],int[]也可以采用方式进行配置. 
 
Map 
 
实例 
POJO类 
package com.xgj.ioc.inject.construct.jihe.map;

import java.util.Map;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取容器注入的Map，遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {

        Map map = pets.getMap();

        for (Map.Entry entry : map.entrySet()) {

            System.out.println("编号Key = " + entry.getKey() + ",品种Value = "
                    + entry.getValue());

        }
    }
}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.map;

import java.util.HashMap;
import java.util.Map;

public class Pets {

    private Map map = new HashMap();

    public Map getMap() {
        return map;
    }

    public void setMap(Map map) {
        this.map = map;
    }

}
 
配置文件 

<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="pets" class="com.xgj.ioc.inject.construct.jihe.map.Pets">
        <property name="map">
            <map>
                <entry>
                    <key>
                        <value>135value>
                    key>
                    <value>catvalue>
                entry>
                <entry>
                    <key>
                        <value>137value>
                    key>
                    <value>birdvalue>
                entry>
                <entry>
                    <key>
                        <value>139value>
                    key>
                    <value>dogvalue>
                entry>
            map>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.map.PetShop">
        <property name="pets" ref="pets" />
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.map;

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

public class InjectMapTest {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/map/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果： 
 
如果Map元素的key和value都是对象，这可以采用以下配置方式 
<entry>
    <key>
        <ref bean="keyBbean"/>
    key>
    <ref bean="valueBean">
entry> 
 
Properties 
 
Propertites键值对可以看做Map类型的特例， Map的键值对可以是任何类型，Properties的键值对只能是字符串，因此配置简单一些，注意Value的配置没有子元素标签 
实例 
POJO类 
package com.xgj.ioc.inject.construct.jihe.properties;

import java.util.Map;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取容器注入的Map，遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {

        Map map = pets.getProperties();

        for (Map.Entry entry : map.entrySet()) {

            System.out.println("编号Key = " + entry.getKey() + ",品种Value = "
                    + entry.getValue());

        }
    }
}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.properties;

import java.util.Properties;

public class Pets {

    private Properties properties;

    public Properties getProperties() {
        return properties;
    }

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

}
 
配置文件 

<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="pets" class="com.xgj.ioc.inject.construct.jihe.properties.Pets">
        <property name="properties">
            <props>
                <prop key="101">catprop>
                <prop key="103">dogprop>
                <prop key="105">birdprop>
            props>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.properties.PetShop">
        <property name="pets" ref="pets" />
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.properties;

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

public class InjectPropertiesTest {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/properties/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果 
 
 
强类型集合 
Java5.0提供了强类型集合的新功能，允许为集合元素指定特定类型。 
实例 
POJO类 
package com.xgj.ioc.inject.construct.jihe.strongType;

import java.util.Map;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取容器注入的Map，遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {

        Map map = pets.getMap();

        for (Map.Entry entry : map.entrySet()) {

            System.out.println("编号Key = " + entry.getKey() + ",品种Value = "
                    + entry.getValue());

        }
    }
}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.strongType;

import java.util.HashMap;
import java.util.Map;

public class Pets {

    private Map<Integer, String> map = new HashMap<Integer, String>();

    public Map<Integer, String> getMap() {
        return map;
    }

    public void setMap(Map<Integer, String> map) {
        this.map = map;
    }

}
 
配置文件 

<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="pets" class="com.xgj.ioc.inject.construct.jihe.strongType.Pets">
        <property name="map">
            <map>
                <entry>
                    <key>
                        
                        <value>111value>
                    key>
                    <value>catvalue>
                entry>
                <entry>
                    <key>
                        <value>113value>
                    key>
                    <value>birdvalue>
                entry>
                <entry>
                    <key>
                        <value>115value>
                    key>
                    <value>dogvalue>
                entry>
            map>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.strongType.PetShop">
        <property name="pets" ref="pets" />
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.strongType;

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

public class InjectStrongTypeTest {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/strongType/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果   
 
集合合并 
Spring支持集合合并的功能，允许子bean继承父bean的同名属性集合元素，并将子bean和父bean中配置的集合属性组合并起来作为最终的bean的属性值。 
实例 
POJO类 
package com.xgj.ioc.inject.construct.jihe.merge;

import java.util.Map;

public class PetShop {

    private Pets pets;

    public void setPets(Pets pets) {
        this.pets = pets;
    }

    /**
     * 
     * 
     * @Title: petsInfo
     * 
     * @Description: 获取容器注入的Map，遍历输出
     * 
     * 
     * @return: void
     */
    public void petsInfo() {

        Map map = pets.getMap();

        for (Map.Entry entry : map.entrySet()) {

            System.out.println("编号Key = " + entry.getKey() + ",品种Value = "
                    + entry.getValue());

        }
    }
}
 
POJO类 
package com.xgj.ioc.inject.construct.jihe.merge;

import java.util.HashMap;
import java.util.Map;

public class Pets {

    private Map<Integer, String> map = new HashMap<Integer, String>();

    public Map<Integer, String> getMap() {
        return map;
    }

    public void setMap(Map<Integer, String> map) {
        this.map = map;
    }

}
 
配置文件 

<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="parentPets"   abstract="true" class="com.xgj.ioc.inject.construct.jihe.merge.Pets">
        <property name="map">
            <map>
                <entry>
                    <key>
                        
                        <value>111value>
                    key>
                    <value>catvalue>
                entry>
                <entry>
                    <key>
                        <value>113value>
                    key>
                    <value>birdvalue>
                entry>
                <entry>
                    <key>
                        <value>115value>
                    key>
                    <value>dogvalue>
                entry>
            map>
        property>
    bean>

    <bean id="pets" parent="parentPets"> 
        <property name="map">
            
            <map merge="true"> 
                <entry>
                    <key>
                        <value>117value>
                    key>
                    <value>monkeyvalue>
                entry>
            map>
        property>
    bean>

    <bean id="petShop" class="com.xgj.ioc.inject.construct.jihe.merge.PetShop">
        <property name="pets" ref="pets" />
    bean>

beans>
 
测试类 
package com.xgj.ioc.inject.construct.jihe.merge;

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

public class InjectStrongTypeTest {

    public static void main(String[] args) {

        ApplicationContext ctx = new ClassPathXmlApplicationContext(
                "classpath:com/xgj/ioc/inject/construct/jihe/merge/beans.xml");

        PetShop shop = ctx.getBean("petShop", PetShop.class);

        shop.petsInfo();

    }
}
 
运行结果
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原始发表：2017/07/20 ，如有侵权请联系 cloudcommunity@tencent.com 删除
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