目录
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一、如可调用构造方法
1、写一个UserInfo类:
public class UserInfo {
public UserInfo(int age,String name) {
System.out.println(age+","+name);
}
}
2、SpringXML文件做如下配置:
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean>
<context:component-scan base-package="com.jd"></context:component-scan>
<!-- 如何调用构造方法 -->
<bean class="com.jd.vo.UserInfo"><!--设置Bean-->
<constructor-arg name="age" value="12"></constructor-arg><!--设置构造方法传入的参数-->
<constructor-arg name="name" value="Tim"></constructor-arg>
</bean>
</beans>
3、写一个Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行,观察结果:
二、为构造方法不同类型参数赋值
1、自定义对象
1)编写UserInfo类
import java.util.Date;
public class UserInfo {
public UserInfo(Date birth) {
System.out.println(birth);
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean><!--配置Date对象-->
<context:component-scan base-package="com.jd"></context:component-scan>
<!-- 给构造方法参数赋值:自定义对象 -->
<bean class="com.jd.vo.UserInfo">
<constructor-arg ref="date"></constructor-arg><!--利用ref属性将Date对象传入-->
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
运行结果说明Date对象已作为参数被传入构造方法。
2、数组
1)编写UserInfo类
public class UserInfo {
public UserInfo(String [] mobiles) {//在构造方法的参数中传入一个数组
for (String mobile : mobiles) {
System.out.println(mobile);//将集合中每个值输出,以验证我们的操作
}
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean>
<context:component-scan base-package="com.jd"></context:component-scan>
<!-- 给构造方法参数赋值:数组 -->
<bean class="com.jd.vo.UserInfo">
<constructor-arg>
<array>
<value>119</value><!--第一种方式:直接给数组元素赋值-->
<bean class="java.lang.String"><!--第二种方式:通过配置Bean创建String类对象的方式给数组元素赋值-->
<constructor-arg value="120"></constructor-arg>
</bean>
</array>
</constructor-arg>
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
观察结果可得,String数组已做为参数传入构造方法。
3、List集合
1)编写UserInfo类
import java.util.List;
public class UserInfo {
public UserInfo(List<Double> moneys) {//在构造方法参数中传入一个List集合,泛型为Double
for (Double money : moneys) {//将集合中每一个元素输出,以验证我们的操作
System.out.println(money);
}
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean>
<context:component-scan base-package="com.jd"></context:component-scan>
<!-- 给构造方法参数赋值:List集合 -->
<bean class="com.jd.vo.UserInfo">
<constructor-arg>
<list>
<value>21000</value>
<value>23222</value>
<value>42455</value>
</list>
</constructor-arg>
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
观察结果可得,List集合已做为参数传入构造方法。
4、Set集合
1)编写UserInfo类
import java.util.Date;
import java.util.Set;
public class UserInfo {
public UserInfo(Set<Date> births) {//在构造方法参数中传入一个List集合,泛型为Date
for (Date birth : births) {//将集合中每一个元素输出,以验证我们的操作
System.out.println(birth);
}
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean>
<context:component-scan base-package="com.jd"></context:component-scan>
<!-- 给构造方法参数赋值:set集合 -->
<bean class="com.jd.vo.UserInfo">
<constructor-arg>
<set>
<ref bean="date"/><!--两种不同的为元素赋值的方式-->
<bean class="java.util.Date"></bean>
</set>
</constructor-arg>
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
观察结果可得,Set集合已做为参数传入构造方法。
5、Map集合
1)编写UserInfo类
import java.util.Map;
import java.util.Properties;
public class UserInfo {
public UserInfo(Map<String,Integer> map) {
for (String name : map.keySet()) {//将集合中每一对key、value输出,以验证我们的操作
System.out.println(name+","+map.get(name));
}
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<bean id="date" class="java.util.Date"></bean>
<context:component-scan base-package="com.jd"></context:component-scan>
<bean id="xiaogang" class="java.lang.String"><!--通过用Bean创建String对象的方式为map集合中的key赋值-->
<constructor-arg value="小刚"></constructor-arg>
</bean>
<!-- 给构造方法参数赋值:map集合 -->
<bean id="ui" class="com.jd.vo.UserInfo">
<constructor-arg>
<map>
<entry key="小明" value="12"></entry>
<entry key-ref="xiaogang" value="23"></entry><!--利用key-ref属性调用String对象-->
</map>
</constructor-arg>
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
观察结果可得,Map集合已做为参数传入构造方法。
6、Properties对象
1)编写UserInfo类
import java.util.Properties;
public class UserInfo {
public UserInfo(Properties properties) {
System.out.println(properties.getProperty("driver"));
System.out.println(properties.getProperty("url"));
System.out.println(properties.getProperty("username"));
System.out.println(properties.getProperty("password"));
}
}
2)配置XML文件
<?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"
xmlns:util="http://www.springframework.org/schema/util"
xmlns:p="http://www.springframework.org/schema/p"
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-4.3.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">
<context:component-scan base-package="com.jd"></context:component-scan>
<bean class="com.jd.vo.UserInfo" >
<constructor-arg>
<props>
<prop key="driver">com.mysql.jdbc.Driver</prop>
<prop key="url">jdbc://127.0.0.1:3306/test</prop>
<prop key="username">root</prop>
<prop key="password">root</prop>
</props>
</constructor-arg>
</bean>
</beans>
3)编写Test类
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.jd.vo.UserInfo;
public class Test {
public static void main(String[] args) {
ClassPathXmlApplicationContext applicationContext = new ClassPathXmlApplicationContext("application.xml");
UserInfo userInfo = applicationContext.getBean(UserInfo.class);
applicationContext.close();
}
}
运行结果:
观察结果可得,Properties对象已做为参数传入构造方法。