1.设值注入:底层调用属性setter方法进行赋值,一定要有setter方法。使用property.
2.构造注入:一定要有带参数的构造方法。使用constructor-arg.
通过设值注入源码为:
1.School类:
public class School {
private String sname;
public void setSname(String sname) {
this.sname = sname;
}
@Override
public String toString() {
return "School [sname=" + sname + "]";
}
}
2.Student类及setter方法
public class Student {
private String name; //成员变量
private int age;
private School school; //自定义类对象
public void setXxx(String name) {
this.name = name;
}
public void setAge(int age) {
this.age = age;
}
public void setSchool(School school) {
this.school = school;
}
@Override
public String toString() {
return "Student [name=" + name + ", age=" + age + ", school=" + school + "]";
}
}
3.XML配置文件
<?xml version="1.0" encoding="UTF-8"?><bean id="mySchool" class="com.abc.di01.School">
<property name="sname" value="清华大学"/>
</bean>
<bean id="student" class="com.abc.di01.Student">
<property name="xxx" value="张三"/>
<property name="age" value="21"/>
<property name="school" ref="mySchool"/>
</bean>
4.测试类MyTest
import org.junit.Test;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.context.support.FileSystemXmlApplicationContext;
import org.springframework.core.io.ClassPathResource;
//设值注入
public class MyTest {
@Test
public void tests01(){
//创建Spring容器对象,加载Spring的配置文件(在类路径下)
String config = "com/abc/di01/applicationContext.xml";
ApplicationContext ac = new ClassPathXmlApplicationContext(config);
Student student = (Student) ac.getBean("student");
System.out.println(student);
}
}
测试结果为:
Student [name=张三, age=21, school=School [sname=清华大学]]
通过构造注入源码为:
1.School类:
public class School {
private String sname;
public void setSname(String sname) {
this.sname = sname;
}
@Override
public String toString() {
return "School [sname=" + sname + "]";
}
}
2.Student类及有参构造方法
public class Student {
private String name; //成员变量
private int age;
private School school; //自定义类对象
public Student(String name, int age, School school) {
super();
this.name = name;
this.age = age;
this.school = school;
}
@Override
public String toString() {
return "Student [name=" + name + ", age=" + age + ", school=" + school + "]";
}
}
3.XML配置文件
<?xml version="1.0" encoding="UTF-8"?><bean id="mySchool" class="com.abc.di02.School">
<property name="sname" value="清华大学"/>
</bean>
<bean id="student" class="com.abc.di02.Student">
<constructor-arg name="name" value="李四"/>
<constructor-arg name="age" value="22"/>
<constructor-arg name="school" ref="mySchool"/>
</bean>
4.测试类MyTest
Student [name=李四, age=22, school=School [sname=清华大学]]