spring笔记（中）

一.复杂属性注入

1.1 这里的复杂属性包括：Array,Set,List,Map,Properties等

1.2 注入操作
实体类：person.java

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Person {

    private String[] names;
    private Set hobby;
    private List subjects;
    private Map phones;
    private Properties friends;
}

1.3 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
       http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="person" class="com.gh.entity.Person">
        <property name="names">
            <array>
                <value>张三</value>
                <value>狗蛋</value>
            </array>
        </property>

        <property name="hobby">
            <set>
                <value>编程</value>
                <value>游戏</value>
            </set>
        </property>

        <property name="subjects">
            <list>
                <value>java</value>
                <value>数据结构</value>
            </list>
        </property>
        
        <property name="friends">
            <props>
                <prop key="fri1">李四</prop>
                <prop key="fri2">王五</prop>
                <prop key="fri3">赵六</prop>
            </props>
        </property>

        <property name="phones">
            <map>
                <entry key="中国移动" value="10086"></entry>
                <entry key="消费者协会" value="12315"></entry>
            </map>
        </property>
    </bean>

</beans>

1.4 测试：获取属性值

    @Test
    public void getPerson(){
        ClassPathXmlApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext.xml");
        Person person = ioc.getBean("person", Person.class);
        System.out.println(person);
    }

二.获取连接对象
2.1 创建dao层接口及实现类

import com.gh.entity.User;

public interface UserDao {

    User findPersonById(Integer id);
}

import com.alibaba.druid.pool.DruidDataSource;
import com.gh.dao.UserDao;
import com.gh.entity.User;

public class UserDaoImpl implements UserDao {

    private DruidDataSource dataSource;

    public DruidDataSource getDataSource() {
        return dataSource;
    }

    public void setDataSource(DruidDataSource dataSource) {
        this.dataSource = dataSource;
    }

    public User findPersonById(Integer id) {
        return null;
    }
}

2.2 创建applicationContext.xml,注入连接对象属性（采用了德鲁伊连接池）

<?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:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
       http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

    <!--加载properties配置文件-->
    <context:property-placeholder location="classpath*:jdbc.properties"></context:property-placeholder>

    <bean id="userDao" class="com.gh.dao.impl.UserDaoImpl">
        <property name="dataSource" ref="dataSource"></property>
    </bean>

    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="url" value="${jdbc.url}"></property>
        <property name="driverClassName" value="${jdbc.driver}"></property>
        <property name="username" value="${jdbc.username}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>


</beans>

2.3 测试能否获取到连接对象

//   测试获取德鲁伊连接对象
    @Test
    public void TestConnection() throws SQLException {
        ClassPathXmlApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext02.xml");
        UserDaoImpl userDao = ioc.getBean("userDao", UserDaoImpl.class);
        System.out.println(userDao.getDataSource().getConnection());
    }

    @Test
    public void TestConnection02() throws SQLException {
        ClassPathXmlApplicationContext ioc = new ClassPathXmlApplicationContext("applicationContext02.xml");
        DruidDataSource dataSource = ioc.getBean("dataSource", DruidDataSource.class);
        System.out.println(dataSource.getConnection());

    }

三.注解开发

3.1 概述：把注入bean的方式由原来在配置文件中书写改为给类、属性、方法添加注解的方式

• @Component——可以给所有类添加
• @Repository——可以给持久层添加
• @Service——可以给业务层添加
• @Controller——可以给控制层添加
• @Bean——给方法添加，将返回结果注入
• @Scope(“singleton”)——设置对象创建模式

//@Component
@Repository
public class UserDaoImpl implements UserDao {

    @Bean
    public DataSource dataSource(){
        DruidDataSource dataSource = new DruidDataSource();
        dataSource.setDriverClassName("com.mysql.jdbc.Driver");
        dataSource.setUrl("jdbc:mysql://localhost:3306/homework?useSSL=false&serverTimezone=GMT&characterEncoding=UTF8&useUnicode=true");
        dataSource.setUsername("root");
        dataSource.setPassword("root");
        return dataSource;
    }

    @Override
    public Integer insertUser(User user) {
        System.out.println("UserDaoImpl...insertUser...");
        return null;
    }
}

3.2 简单注解赋值
@values——可以给基本类型，String ,Date进行赋值，如

public class User {
    @Value("1")
    private Integer id;
    
    @Value("张三")
    private String username;
    
    @Value("sanzhang")
    private String password;
}

3.3 对象注解——给类中被引用的对象寻找注入的数据

3.4 生命周期相关注解

• @PostConstruct——初始化注解
• @PreDestory——注销方法注解

    @PostConstruct
    public void init(){
        System.out.println("User...init");
    }

    @PreDestroy
    public void destroy(){
        System.out.println("User...destroy");
    }

3.5 配置相关注解

• @Configuration——把此类标记为配置
• @ComponentScans—— 扫描文件
• @Import—— 导入其他的配置文件
• @PropertySource—— 导入配置文件

标签：笔记,spring,private,dataSource,DruidDataSource,import,public,User
来源： https://blog.csdn.net/qq_46083662/article/details/118545319