Notes 1.2 springboot a configuration attributes injection

Method 1: Java form

　　Use the comment

　　 1. @Configuration // annotation indicates that the class is a class configuration

　　 2. @ PropertySource ( "classpath: jdbc.properties") // reads the configuration file attributes    

　　 3. @ Bean // The statement notes on the method, the method's return value added bean container

　　 4. @ value injection properties

 

　　Step 1: Configure class

　　

@Configuration   // This class represents an annotation configuration class 
@PropertySource ( "CLASSPATH: the jdbc.properties") // read the profile property 
public  class JdbcConfig {

    @Value ( "jdbc.driverClassName $ {}")   // injection attribute 
    String driverClassName;
    @Value("${jdbc.url}")
    String url;
    @Value("${jdbc.username}")
    String username;
    @Value("${jdbc.password}")
    String password;


         @Bean   // of the annotations in the method declaration, the return value is added bean container 
        public the DataSource getDataSource () {
             DruidDataSource dataSource = new DruidDataSource();
             dataSource.setDriverClassName(driverClassName);
             dataSource.setUrl(url);
             dataSource.setUsername(username);
             dataSource.setPassword(password);
             return dataSource;
        }
}

 

　　　　Step Two: Profile

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/test
jdbc.username=root
jdbc.password=root