IOC(xml bean 管理)注入内_外部bean、级联赋值、集合类型
注入属性-外部bean
- 创建两个类service类和dao类
- 在service调用dao里面的方法
创建UserService
java
public class UserService {
public void add(){
System.out.println("service add ...........");
// 原始方式
// 创建UserDao对象
// UserDao userDao = new UserDaoImpl();
//.update();
}
}
创建UserDao接口
java
public interface UserDao {
public void update();
}
创建UserDao接口实现类,UserDaoImpl
java
public class UserDaoImpl implements UserDao{
@Override
public void update() {
System.out.println("dao update ..........");
}
}
使用spring来实现
创建UserDao这个类型的属性,生成set方法,也可以使用有参构造方法
java
public class UserService {
private UserDao userDao;
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
public void add(){
System.out.println("service add ...........");
}
}
配置spring文件
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.xsd">
<!-- service和dao对象创建 -->
<bean id="userService" class="cn.unuuc.spring5.service.UserService">
<!--注入userDao-->
<!--name:属性名称-->
<property name="userDao" ref="userDao"></property>
</bean>
<bean id="userDao" class="cn.unuuc.spring5.dao.UserDaoImpl"></bean>
</beans>
测试类
java
@Test
public void test01(){
ApplicationContext context = new FileSystemXmlApplicationContext("spring-di.xml");
UserService userService = context.getBean("userService", UserService.class);
userService.add();
}
注入属性-内部bean和级联赋值
(1)一对多关系:部门和员工 一个部门有多个员工,一个员工属于一个部门。部门是一,员工是多 (2)在实体类之间表示一对多关系
(3)在配置文件中进行相关配置
内部bean配置
创建Emp员工类和Dept部门类。
java
package cn.unuuc.spring5.bean;
/**
* 员工类
*/
public class Emp {
private String EName;
private String gender;
private Dept dept;
public void setDept(Dept dept) {
this.dept = dept;
}
public void setEName(String EName) {
this.EName = EName;
}
public void setGender(String gender) {
this.gender = gender;
}
public void add(){
System.out.println(EName+":"+gender+":"+dept.toString());
}
}
java
package cn.unuuc.spring5.bean;
import java.util.ArrayList;
/**
* 部门类
*/
public class Dept {
private String DName;
public void setDName(String dName) {
this.DName = dName;
}
@Override
public String toString() {
return "Dept{" +
"DName='" + DName + '\'' +
'}';
}
}
编写spring配置文件
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.xsd">
<!-- 内部bean -->
<bean id="emp" class="cn.unuuc.spring5.bean.Emp">
<!--先设置两个普通属性-->
<property name="EName" value="lucy"></property>
<property name="gender" value="女"></property>
<!--设置对象类型属性-->
<property name="dept">
<bean id="dept" class="cn.unuuc.spring5.bean.Dept">
<property name="DName" value="安保部"></property>
</bean>
</property>
</bean>
</beans>
测试类
java
@Test
public void test02(){
ApplicationContext context = new FileSystemXmlApplicationContext("spring-bean3.xml");
Emp emp = context.getBean("emp", Emp.class);
emp.add();
}
级联赋值
第一种
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.xsd">
<!-- 内部bean -->
<bean id="emp" class="cn.unuuc.spring5.bean.Emp">
<!--先设置两个普通属性-->
<property name="EName" value="lucy"></property>
<property name="gender" value="女"></property>
<!--级联赋值-->
<property name="dept" ref="dept"></property>
</bean>
<bean id="dept" class="cn.unuuc.spring5.bean.Dept">
<property name="DName" value="财务部"></property>
</bean>
</beans>
第二种
这种方式需要在Emp类中实现dept的get方法
这里的原理是: a. 创建一个外部bean dept,这个dept bean不需要设置属性(设置了后面也会被覆盖); b. 在emp bean内部,先获取外部dept对象, c. 在通过dept.DName方式对获取到的dept对象进行赋值。
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.xsd">
<bean id="emp" class="cn.unuuc.spring5.bean.Emp">
<!--先设置两个普通属性-->
<property name="EName" value="lucy"></property>
<property name="gender" value="女"></property>
<!--级联赋值-->
<property name="dept" ref="dept"></property>
<property name="dept.DName" value="技术部"></property>
</bean>
<bean id="dept" class="cn.unuuc.spring5.bean.Dept">
<property name="DName" value="财务部"></property>
</bean>
</beans>
xml注入集合属性
创建一个Stu类,编写不同类型的属性(需要生成set方法)
java
package cn.unuuc.spring5.collectiontype;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Set;
public class Stu {
// 1. 数组类型的属性
private String[] courses;
// 2. List集合类型属性
private List<String> list;
// 3. Map类型属性
private Map<String,String> map;
// 4. Set类型属性
private Set<String> sets;
public void setSets(Set<String> sets) {
this.sets = sets;
}
public void setList(List<String> list) {
this.list = list;
}
public void setMap(Map<String, String> map) {
this.map = map;
}
public void setCourses(String[] courses) {
this.courses = courses;
}
@Override
public String toString() {
return "Stu{" +
"courses=" + Arrays.toString(courses) +
", list=" + list +
", map=" + map +
", sets=" + sets +
'}';
}
}
编写配置文件
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.xsd">
<!-- 集合类型的属性注入 -->
<!-- 创建对象 -->
<bean id="stu" class="cn.unuuc.spring5.collectiontype.Stu">
<!-- 数组类型属性注入 -->
<property name="courses">
<!-- list 标签 和 array 标签都可以 -->
<array>
<value>数据结构</value>
<value>操作系统</value>
<value>计算机网络</value>
</array>
</property>
<!-- List类型属性注入 -->
<property name="list">
<list>
<value>张三</value>
<value>李四</value>
</list>
</property>
<!-- Map类型属性注入 -->
<property name="map">
<map>
<entry key="Java" value="java"></entry>
<entry key="PHP" value="php"></entry>
</map>
</property>
<!-- Set类型属性注入 -->
<property name="sets">
<set>
<value>MySQL</value>
<value>Redis</value>
</set>
</property>
</bean>
</beans>
测试结果
xml注入集合属性补充
在集合里面设置对象类型值
创建Course类,表示课程学生所学的多门课程类
java
package cn.unuuc.spring5.collectiontype;
public class Course {
private String cname;// 课程名称
public void setCname(String cname) {
this.cname = cname;
}
@Override
public String toString() {
return "Course{" +
"cname='" + cname + '\'' +
'}';
}
}
在Stu类种添加属性并添加set方法
java
// 5. 学生所学多门课程
private List<Course> courseList;
public void setCourseList(List<Course> courseList) {
this.courseList = courseList;
}
配置文件
java
<?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.xsd">
<!-- 集合类型的属性注入 -->
<!-- 创建对象 -->
<bean id="stu" class="cn.unuuc.spring5.collectiontype.Stu">
<!-- List集合类型,值是对象 -->
<property name="courseList">
<list>
<ref bean="course1"></ref>
<ref bean="course2"></ref>
<ref bean="course3"></ref>
</list>
</property>
</bean>
<!--创建多个Course对象-->
<bean id="course1" class="cn.unuuc.spring5.collectiontype.Course">
<property name="cname" value="数据结构"></property>
</bean>
<bean id="course2" class="cn.unuuc.spring5.collectiontype.Course">
<property name="cname" value="操作系统"></property>
</bean>
<bean id="course3" class="cn.unuuc.spring5.collectiontype.Course">
<property name="cname" value="计算机网络"></property>
</bean>
</beans>
测试
把集合注入的部门提取出来
创建一个Book类用来测试
java
package cn.unuuc.spring5.collectiontype;
import java.util.List;
public class Book {
private List<String> list;
@Override
public String toString() {
return "Book{" +
"list=" + list +
'}';
}
public void setList(List<String> list) {
this.list = list;
}
}
在spring的配置文件种引入一个命名空间 util
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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">
</beans>
使用util标签完成list集合注入的提取
java
<?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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">
<!-- 提取list集合类型属性注入 -->
<util:list id="bookList">
<!--如果是对象则用ref标签-->
<value>书1</value>
<value>书2</value>
<value>书3</value>
</util:list>
</beans>
使用提取出来的
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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">
<!-- 提取list集合类型属性注入 -->
<util:list id="bookList">
<!--如果是对象则用ref标签-->
<value>书1</value>
<value>书2</value>
<value>书3</value>
</util:list>
<!-- 使用提取的list集合类型属性注入 -->
<bean id="book" class="cn.unuuc.spring5.collectiontype.Book">
<property name="list" ref="bookList"></property>
</bean>
</beans>