SpringBoot01 java的配置方式

1、添加依赖 pom.xml

<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0"         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">    <modelVersion>4.0.0</modelVersion>    <groupId>springboot</groupId>    <artifactId>springboot</artifactId>    <version>1.0-SNAPSHOT</version>    <parent>        <groupId>org.springframework.boot</groupId>        <artifactId>spring-boot-starter-parent</artifactId>        <version>1.4.0.RELEASE</version>    </parent>    <dependencies>        <dependency>            <groupId>org.springframework.boot</groupId>            <artifactId>spring-boot-starter-web</artifactId>        </dependency>    </dependencies>    <build>        <plugins>            <plugin>                <groupId>org.springframework.boot</groupId>                <artifactId>spring-boot-maven-plugin</artifactId>            </plugin>        </plugins>    </build></project>

2、创建一个实体类

package com.lgz.springboot.config;public class User {    private String username;    private String password;    private Integer age;    //此处省略get set方法}

3、模拟Dao

package com.lgz.springboot.config;import java.util.ArrayList;import java.util.List;/*** * 模拟数据库操作 */public class UserDao {    public List<User> getUserList() {        List<User> result = new ArrayList<User>();        for (int i = 0; i < 10; i++) {            User user = new User();            user.setAge(i);            user.setPassword("password" + i);            user.setUsername("name" + i);            result.add(user);        }        return result;    }}

4、模拟service

package com.lgz.springboot.config;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.List;@Servicepublic class UserService {    @Autowired    private UserDao userDao;    public List<User> getUserList() {        return userDao.getUserList();    }}

5、创建java配置文件

package com.lgz.springboot.config;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.ComponentScan;import org.springframework.context.annotation.Configuration;@Configuration //表名该类是spring的配置，相当于xml文件@ComponentScan(basePackages = "com.lgz.springboot.config") //配置扫描包public class SpringConfig {    @Bean //说明这是一个Bean对象，相当于xml中的<bean>    public UserDao getUserDao() {        return new UserDao();    }}

6、测试

package com.lgz.springboot.config;import org.springframework.context.annotation.AnnotationConfigApplicationContext;import java.util.List;public class Main {    public static void main(String[] args) {        //通过java配置来实例化Spring容器        AnnotationConfigApplicationContext context =          new AnnotationConfigApplicationContext(SpringConfig.class);        //获取对象        UserService userService = context.getBean(UserService.class);        List<User> list = userService.getUserList();        for (User user : list) {            System.out.println("name=" + user.getUsername() + " psw=" + user.getPassword() + " age=" + user.getAge());        }        context.destroy();    }}

测试结果打印

name=name0 psw=password0 age=0name=name1 psw=password1 age=1name=name2 psw=password2 age=2name=name3 psw=password3 age=3name=name4 psw=password4 age=4name=name5 psw=password5 age=5name=name6 psw=password6 age=6name=name7 psw=password7 age=7name=name8 psw=password8 age=8name=name9 psw=password9 age=9