Java Spring 学习笔记 008（DI依赖注入环境）

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一、构造器注入

前面已经说过了。

二、Set方式注入【重点】

• 依赖注入：Set注入
  • 依赖：bean对象的创建依赖于容器！
  • 注入：bean对象中的所有属性，有容器来注入！
• 环境搭建：
  • 复杂类型

  package com.kuang.pojo;
  
  public class Address {
  
      private String address;
  
      public String getAddress() {
          return address;
      }
  
      public void setAddress(String address) {
          this.address = address;
      }
  
      @Override
      public String toString() {
          return "Address{" +
                  "address='" + address + '\'' +
                  '}';
      }
  }
  
  

  • 真实测试对象

  package com.kuang.pojo;
  
  import java.util.*;
  
  public class Student {
  
      private String name;
      private Address address;
      private String[] books;
      private List<String> hobbies;
      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> getHobbies() {
          return hobbies;
      }
  
      public void setHobbies(List<String> hobbies) {
          this.hobbies = hobbies;
      }
  
      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) +
                  ", hobbies=" + hobbies +
                  ", card=" + card +
                  ", games=" + games +
                  ", wife='" + wife + '\'' +
                  ", info=" + info +
                  '}';
      }
  }
  
  

  • applicationContext.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.kuang.pojo.Student">
          <!-- 第一种：普通值注入，value -->
          <property name="name" value="墨倾池"/>
      </bean>
  
  </beans>
  

  • 测试类

  import com.kuang.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("applicationContext.xml");
          Student student = (Student) context.getBean("student");
          System.out.println(student);
      }
  
  }
  
  

三、拓展方式注入