詳解Spring基於xml的兩種依賴注入方式
阿新 • • 發佈:2020-01-07
1)使用構造器注入bean
實體類:使用者類
public class User { private String name; private UserMessage userMessage; public User() { } public User(String name,UserMessage userMessage) { this.name = name; this.userMessage = userMessage; } public String getName() { return name; } public void setName(String name) { this.name = name; } public UserMessage getUserMessage() { return userMessage; } public void setUserMessage(UserMessage userMessage) { this.userMessage = userMessage; } @Override public String toString() { return "User{" + "name='" + name + '\'' + ",userMessage=" + userMessage + '}'; } }
實體類:使用者資訊類
public class UserMessage { private String username; private String password; public UserMessage() { } public UserMessage(String username,String password) { this.username = username; this.password = password; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } @Override public String toString() { return "UserMessage{" + "username='" + username + '\'' + ",password='" + password + '\'' + '}'; } }
配置檔案
<?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"> <!-- 註冊UserMessage類 --> <bean id="userMessage" class="entity.UserMessage"> <constructor-arg name="username" value="scott"></constructor-arg> <constructor-arg name="password" value="tiger"></constructor-arg> </bean> <!-- 註冊User類 --> <bean id="user" class="entity.User"> <constructor-arg name="name" value="tom"></constructor-arg> <constructor-arg name="userMessage" ref="userMessage"></constructor-arg> </bean> </beans>
測試類
public class TestDI { @Test public void test() { ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml"); User user = ac.getBean("user",User.class); System.out.println(user); } }
測試結果
User{name='tom',userMessage=UserMessage{username='scott',password='tiger'}}
2)使用setter方法注入bean
實體類:使用者類
public class User { private String name; private UserMessage userMessage; public User() { } public User(String name,password='" + password + '\'' + '}'; } }
配置檔案
<?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"> <!-- 註冊UserMessage類 --> <bean id="userMessage" class="entity.UserMessage"> <property name="username" value="scott"></property> <property name="password" value="tiger"></property> </bean> <!-- 註冊User類 --> <bean id="user" class="entity.User"> <property name="name" value="tom"></property> <property name="userMessage" ref="userMessage"></property> </bean> </beans>
測試類
public class TestDI { @Test public void test() { ApplicationContext ac = new ClassPathXmlApplicationContext("applicationContext.xml"); User user = ac.getBean("user",User.class); System.out.println(user); } }
測試結果
User{name='tom',password='tiger'}}
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支援我們。