标签:www 红楼梦 this 西游 static 三国 看电影 标识 null
<!--别名,如果添加了别名,我们也可以使用别名获取到这个对象-->
<alias name="user" alias="userAlias"/>
<!--
id:bean的唯一标识符,也就是相当于我们学的对象名
class:bean对象所对应的全限定名:包名+类名
name:也是别名,而且name可以同时取多个别名
-->
<bean id="userT" class="com.rui.pojo.UserT" name="user2 u2,u3;u4">
</bean>
这个import,一般用于团队开发使用,他可以将多个配置文件,导入合并为一个
假设现在项目中有多个人开发,这三个人负责不同的类开发,不同的类需要注册在不同的bean中,我们可以利用import将所有人的beans.xml合并为一个总的!
<?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
https://www.springframework.org/schema/beans/spring-beans.xsd">
<import resource="beans.xml"/>
<import resource="beans2.xml"/>
<import resource="beans3.xml"/>
</beans>
使用的时候,直接使用总的配置就可以了
前面已经说过
【环境搭建】
复杂类型
package com.rui.pojo;
public class Address {
private String address;
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
}
真实测试对象
package com.rui.pojo;
import java.util.*;
public class Student {
private String name;
private Address address;
private String[] books;
private List<String> hobbys;
private Map<String,String> card;
private Set<String> games;
private String wife;
private Properties info;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Address getAddress() {
return address;
}
public void setAddress(Address address) {
this.address = address;
}
public String[] getBooks() {
return books;
}
public void setBooks(String[] books) {
this.books = books;
}
public List<String> getHobbys() {
return hobbys;
}
public void setHobbys(List<String> hobbys) {
this.hobbys = hobbys;
}
public Map<String, String> getCard() {
return card;
}
public void setCard(Map<String, String> card) {
this.card = card;
}
public Set<String> getGames() {
return games;
}
public void setGames(Set<String> games) {
this.games = games;
}
public String getWife() {
return wife;
}
public void setWife(String wife) {
this.wife = wife;
}
public Properties getInfo() {
return info;
}
public void setInfo(Properties info) {
this.info = info;
}
@Override
public String toString() {
return "Student{" +
"name='" + name + '\'' +
", address=" + address +
", books=" + Arrays.toString(books) +
", hobbys=" + hobbys +
", card=" + card +
", games=" + games +
", wife='" + wife + '\'' +
", info=" + info +
'}';
}
}
beans.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
https://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="student" class="com.rui.pojo.Student">
<!--第一种,普通注入,value-->
<property name="name" value="尹锐"/>
</bean>
</beans>
测试类
package com.rui;
import com.rui.pojo.Student;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class MyTest {
public static void main(String[] args) {
ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
Student student = (Student) context.getBean("student");
System.out.println(student.getName());
}
}
完善注入信息
<?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
https://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="address" class="com.rui.pojo.Address">
<property name="address" value="杭州"></property>
</bean>
<bean id="student" class="com.rui.pojo.Student">
<!--第一种,普通注入,value-->
<property name="name" value="尹锐"/>
<!--第二种,Bean注入,ref-->
<property name="address" ref="address"/>
<!--数组注入,ref-->
<property name="books">
<array>
<value>红楼梦</value>
<value>西游记</value>
<value>水浒传</value>
<value>三国演义</value>
</array>
</property>
<!--List-->
<property name="hobbys">
<list>
<value>听歌</value>
<value>敲代码</value>
<value>看电影</value>
</list>
</property>
<!--Map-->
<property name="card">
<map>
<entry key="身份证" value="111222333344445555"/>
<entry key="银行卡" value="11123123123123123123"/>
</map>
</property>
<!--Set-->
<property name="games">
<set>
<value>LOL</value>
<value>COC</value>
<value>BOB</value>
</set>
</property>
<!--null-->
<property name="wife">
<null/>
</property>
<!--Properties-->
<property name="info">
<props>
<prop key="driver">171030338</prop>
<prop key="url">171030338</prop>
<prop key="username">171030338</prop>
<prop key="password">171030338</prop>
</props>
</property>
</bean>
</beans>
我们可以使用p命名空间和c命名空间进行注入
官方解释:
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"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:c="http://www.springframework.org/schema/c"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd">
<!--p命名空间注入,可以直接注入属性的值:property-->
<bean id="user" class="com.rui.pojo.User" p:name="尹锐" p:age="18"/>
<!--c命名空间注入,通过构造器注入:construct-args-->
<bean id="user2" class="com.rui.pojo.User" c:age="18" c:name="尹锐"/>
</beans>
测试:
@Test
public void test2() {
ApplicationContext context = new ClassPathXmlApplicationContext("userbeans.xml");
User user = (User) context.getBean("user2");
System.out.println(user);
}
注意点:p命名空间和c命名空间不能直接使用,需要导入xml约束!
xmlns:p="http://www.springframework.org/schema/p"
xmlns:c="http://www.springframework.org/schema/c"
单例模式(Spring默认机制)
<bean id="user2" class="com.rui.pojo.User" c:age="18" c:name="尹锐" scope="singleton"/>
原型模式:每次从容器中get的时候,都会产生一个新对象
<bean id="user2" class="com.rui.pojo.User" c:age="18" c:name="尹锐" scope="prototype"/>
其余的request、session、application、这些只能在web开发中用到!
标签:www 红楼梦 this 西游 static 三国 看电影 标识 null
原文地址:https://www.cnblogs.com/MrKeen/p/12028961.html