springDI应用二

数组注入

  • 一个有数组的实体类，配置如下：
import java.util.Arrays;

public class TestBean {
    private String name;
    private Integer age;
    private Computer[] computers;

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

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

    public void setComputers(Computer[] computers) {
        this.computers = computers;
    }

    @Override
    public String toString() {
        return "TestBean{" +
                "name='" + name + '\'' +
                ", age=" + age +
                ", computers=" + Arrays.toString(computers) +
                '}';
    }
}
  • 配置文件如下：（包含了嵌套和外部引用的两种方法）
    <bean name="c1" class="domain.Computer"></bean>
    <bean name="c2" class="domain.Computer"></bean>
    <bean name="c3" class="domain.Computer"></bean>


    <bean id="testBean" class="domain.TestBean">
        <property name="name" value="zhangfei"></property>
        <property name="age" value="19"></property>
        <property name="computers">
            <array value-type="domain.Computer">
                //嵌套方法
                <bean class="domain.Computer">
                    <property name="name" value="小米"></property>
                </bean>
                <bean class="domain.Computer">
                    <property name="name" value="华为"></property>
                </bean>
                <bean class="domain.Computer">
                    <property name="name" value="苹果"></property>
                </bean>
              //引用方法
                <ref bean="c1"></ref>
                <ref bean="c2"></ref>
                <ref bean="c3"></ref>
            </array>
        </property>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果(因为嵌套的对象没有赋值，输出的结果都是null)
TestBean{name='zhangfei', age=19, computers=[Computer{brand='null', name='小米', price=null}, Computer{brand='null', name='华为', price=null}, Computer{brand='null', name='苹果', price=null}, Computer{brand='null', name='null', price=null}, Computer{brand='null', name='null', price=null}, Computer{brand='null', name='null', price=null}]}

list注入(非自定义类型）

  • 一个有list的实体类，配置如下：(将上面数组改为list)
  • 配置文件如下：
    <bean name="testBean" class="domain.TestBean">
        <constructor-arg name="name" value="machao" type="java.lang.String"></constructor-arg>
        <constructor-arg name="age" value="25" type="java.lang.Integer"></constructor-arg>
        <constructor-arg name="liststring" type="java.util.List">
            <list value-type="java.lang.String">
                <value>1111</value>
                <value>aaaa</value>
                <value>cccc</value>
                <value>dddd</value>
            </list>
        </constructor-arg>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果(因为嵌套的对象没有赋值，输出的结果都是null)
TestBean{name='machao', age=25, liststring=[1111, aaaa, cccc, dddd]}

list注入(自定义类型）

  • 一个有list的实体类，配置如下：(将上面list<String>改为list<Computer)
  • 配置文件如下：（包含了嵌套和外部引用的两种方法）
    <bean name="c1" class="domain.Computer"></bean>

    <bean id="testBean" class="domain.TestBean">
        <constructor-arg name="name" value="huangzhogn" type="java.lang.String"></constructor-arg>
        <constructor-arg name="age" value="224"></constructor-arg>
        <constructor-arg name="listcomputer" type="java.util.List">
            <list value-type="domain.Computer">
                <bean class="domain.Computer">
                    <property name="name" value="17pro"></property>
                    <property name="brand" value="小米"></property>
                    <property name="price" value="9999"></property>
                </bean>
                <bean class="domain.Computer"></bean>
                <bean class="domain.Computer"></bean>
                <ref bean="c1"></ref>
            </list>
        </constructor-arg>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果
TestBean{name='huangzhogn', age=224, listcomputer=[Computer{brand='小米', name='17pro', price=9999.0}, Computer{brand='null', name='null', price=null}, Computer{brand='null', name='null', price=null}, Computer{brand='null', name='null', price=null}]}

set注入(基本类型、对象、set）

  • 一个有String、Computer、Set的实体类，配置如下：
public class TestBean {
    private String name;
    private Computer computer;
    private Set<String> setstring;

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

    public void setComputer(Computer computer) {
        this.computer = computer;
    }

    public void setSetstring(Set<String> setstring) {
        this.setstring = setstring;
    }

    public TestBean(String name, Computer computer, Set<String> setstring) {
        this.name = name;
        this.computer = computer;
        this.setstring = setstring;
    }

    @Override
    public String toString() {
        return "TestBean{" +
                "name='" + name + '\'' +
                ", computer=" + computer +
                ", setstring=" + setstring +
                '}';
    }
}
  • 配置文件如下：
    <bean id="testBean" class="domain.TestBean">
        <constructor-arg name="name" type="java.lang.String">
            <value>guanyu</value>
        </constructor-arg>
        <constructor-arg name="computer" type="domain.Computer">
            <bean class="domain.Computer"></bean>
        </constructor-arg>
        <constructor-arg name="setstring" type="java.util.Set">
            <set value-type="java.lang.String">
                <value>aaa</value>
                <value>bbb</value>
                <value>ccc</value>
            </set>
        </constructor-arg>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果
TestBean{name='guanyu', computer=Computer{brand='null', name='null', price=null}, setstring=[aaa, bbb, ccc]}

Map注入(基本类型、对象、map）

  • 一个实体类，配置如下：
    private String name;
    private Computer computer;
//    private Set<String> setstring;
    private Map<Integer,String> map;
    set 方法 有参 无参构造方法...
  • 配置文件如下：
    <bean id="testBean" class="domain.TestBean">
        <property name="name" value="zhaoyun"></property>
        <property name="computer">
            <bean class="domain.Computer"></bean>
        </property>
        <property name="map">
            <map key-type="java.lang.Integer" value-type="java.lang.String">
                <entry key="1" value="aaa"></entry>
                <entry key="2" value="bbb"></entry>
                <entry key="3" value="ccc"></entry>
            </map>
        </property>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果
TestBean{name='zhaoyun', computer=Computer{brand='null', name='null', price=null}, map={1=aaa, 2=bbb, 3=ccc}}

Map注入(自定义类型）

  • 一个实体类，配置如下：
    private String name;
    private Computer computer;
//    private Set<String> setstring;
    private Map<Integer,String> map;
    set 方法 有参 无参构造方法...
  • 配置文件如下：
      <bean id="testBean" class="domain.TestBean">
    <property name="name" value="zhaoyun"></property>
    <property name="computer">
        <bean class="domain.Computer"></bean>
    </property>
        <property name="map">
            <map key-type="java.lang.Integer" value-type="domain.Computer">
                <entry key="1">
                    <bean class="domain.Computer">
                        <property name="brand" value="小米"></property>
                        <property name="price" value="18888"></property>
                        <property name="name" value="28pro"></property>
                    </bean>
                </entry>
                <entry key="2">
                    <bean class="domain.Computer">
                        <property name="brand" value="华为"></property>
                        <property name="price" value="13888"></property>
                        <property name="name" value="30pro"></property>
                    </bean>
                </entry>
                <entry key="3">
                    <bean class="domain.Computer">
                        <property name="brand" value="外星人"></property>
                        <property name="price" value="19999"></property>
                        <property name="name" value="40pro"></property>
                    </bean>
                </entry>
            </map>
        </property>
    </bean>
  • 代码如下：
        BeanFactory factory1 = new ClassPathXmlApplicationContext("ApplicationContext.xml");
        TestBean bean = (TestBean) factory1.getBean("testBean");
        System.out.println(bean);
  • 运行结果
TestBean{name='zhaoyun', computer=Computer{brand='null', name='null', price=null}, map={1=Computer{brand='小米', name='28pro', price=18888.0}, 2=Computer{brand='华为', name='30pro', price=13888.0}, 3=Computer{brand='外星人', name='40pro', price=19999.0}}}
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