有时候有这样子的情景,我们想把配置文件的信息,读取并自动封装成实体类,这样子,我们在代码里面使用就轻松方便多了,这时候,我们就可以使用@ConfigurationProperties,它可以把同类的配置信息自动封装成实体类
首先在配置文件里面,这些信息是这样子滴
connection.username=admin
connection.password=kyjufskifas2jsfs
connection.remoteAddress=192.168.1.1
这时候我们可以定义一个实体类在装载配置文件信息
@Component @ConfigurationProperties(prefix="connection") public class ConnectionSettings { private String username; private String remoteAddress; private String password ; public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getRemoteAddress() { return remoteAddress; } public void setRemoteAddress(String remoteAddress) { this.remoteAddress = remoteAddress; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
我们还可以把@ConfigurationProperties还可以直接定义在@bean的注解上,这是bean实体类就不用@Component和@ConfigurationProperties了
@SpringBootApplication public class DemoApplication{ //... @Bean @ConfigurationProperties(prefix = "connection") public ConnectionSettings connectionSettings(){ return new ConnectionSettings(); } public static void main(String[] args) { SpringApplication.run(DemoApplication.class, args); } }
然后我们需要使用的时候就直接这样子注入
@RestController @RequestMapping("/task") public class TaskController { @Autowired ConnectionSettings conn; @RequestMapping(value = {"/",""}) public String hellTask(){ String userName = conn.getUsername(); return "hello task !!"; } }
如果发现@ConfigurationPropertie不生效,有可能是项目的目录结构问题,
你可以通过@EnableConfigurationProperties(ConnectionSettings.class)来明确指定需要用哪个实体类来装载配置信息
@Configuration @EnableConfigurationProperties(ConnectionSettings.class) public class MailConfiguration { @Autowired private MailProperties mailProperties; @Bean public JavaMailSender javaMailSender() { // omitted for readability } }