在@Bean方法上使用@ConfigurationProperties注释

spring.datasource.url = [url]spring.datasource.username = [username]spring.datasource.password = [password]spring.datasource.driverClassName = oracle.jdbc.OracleDriver@Bean@ConfigurationProperties(prefix="spring.datasource")public DataSource dataSource() {    return new DataSource();}

这里的DataSource类具有属性url，用户名，密码，driverClassName，因此spring boot将它们映射到创建的对象。

DataSource类的示例：

public class DataSource {    private String url;    private String driverClassName;    private String username;    private String password;    //getters & setters, etc.}

换句话说，这与使用构造型注释（@ Component，@ Service等）初始化某些bean的效果相同，例如

@Component@ConfigurationProperties(prefix="spring.datasource")public class DataSource {    private String url;    private String driverClassName;    private String username;    private String password;    //getters & setters, etc.}