public class Student {   //学生实体类    private  String   name;  //姓名    private  Integer  age;  //年龄    private  Grade   grade;  //年级    @Override    public String toString() {        return "Student [name=" + name + ", age=" + age + ", grade=" + grade                + "]";    }        public Student() {        super();    }    public Student(String name, Integer age, Grade grade) {        super();        this.name = name;        this.age = age;        this.grade = grade;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public Integer getAge() {        return age;    }    public void setAge(Integer age) {        this.age = age;    }    public Grade getGrade() {        return grade;    }    public void setGrade(Grade grade) {        this.grade = grade;    }      //根据年龄的不同返回age不同的值    public  Integer   changeAge(){        return (this.age>25)?20:this.age;    }    }

public class Grade {   //年级实体类    private String  name;  //年级名称    @Override    public String toString() {        return "Grade [name=" + name + "]";    }    public Grade() {        super();    }    public Grade(String name) {        super();        this.name = name;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }}

<?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         http://www.springframework.org/schema/beans/spring-beans.xsd">  <!--  spel 注入    spring el表达式   需要实体类中 有对应的get（）                       第一个学生 -->     <bean id="student1" class="cn.bdqn.bean.Student">     <property name="name" value="小黑"/>     <property name="age" value="#{T(java.lang.Math).random()*50}"/>     </bean>         <!-- 第二个学生  name属性值 是 第一个学生的   age值  是方法中获取的  -->     <bean id="student2" class="cn.bdqn.bean.Student">     <property name="name" value="#{student1.name}"/>    <!--  <property name="age" value="http://www.mamicode.com/#{student1.age>30?25:student1.age}"/> -->       <!--直接把年龄的判断写在类中 并且得到返回值  -->     <property name="age" value="#{student1.changeAge()}"/>     </bean>                  <!--匿名内部bean  年级只属于指定的Student  -->   <!--   <bean id="student" class="cn.bdqn.bean.Student">     <property name="name" value="http://www.mamicode.com/小黑"/>     <property name="age" value="http://www.mamicode.com/50"/>     <property name="grade">      其他的bean中 无法访问        <bean id="grade" class="cn.bdqn.bean.Grade" p:name="1年级"/>     </property>     </bean> -->    </beans>

public class StudentTest {            //使用spel注入    @Test    public  void  test01(){        ApplicationContext context=                new ClassPathXmlApplicationContext("applicationContext.xml");        Student student1=(Student) context.getBean("student1");         Student student2=(Student) context.getBean("student2");        System.out.println("student1信息："+student1);        System.out.println("student2信息："+student2);    }        //匿名内部bean    @Test    public  void  test02(){        ApplicationContext context=                new ClassPathXmlApplicationContext("applicationContext.xml");        Student student=(Student) context.getBean("student");        System.out.println("student信息："+student);    }}