configurationproperties is an unknown property - mysql

Question

I am having problem understanding the usage of #ConfigurationProperties. In my application properties file, all of the variables "is an unknown property" with yellow underline. I run the application but the same thing happens. Is there a way to link the configuration at application.properties to my datasource function?
If I use
spring.datasource.url = jdbc:mysql://127.0.0.1/trs?useSSL=false
it works just fine but it i use app.datasource.url it wouldn't work
My application.properties file
# Primary DataSource configuration
app.datasource.url=jdbc:mysql://127.0.0.1/trs?useSSL=false
app.datasource.username=user
app.datasource.password=pass
my primary .java file
#ConfigurationProperties(prefix="app.datasource")
#Primary
#Bean
public DataSource dataSource() {
final DriverManagerDataSource dataSource = new DriverManagerDataSource();
dataSource.setDriverClassName("com.mysql.jdbc.Driver");
dataSource.setUrl("jdbc:mysql://127.0.0.1/trs?useSSL=false");
dataSource.setUsername("user");
dataSource.setPassword("pass");
return dataSource;
}

Answer 1

For your application.properties, you need a corresponding java class to load the configuration in a bean. Like this -
#ConfigurationProperties(prefix="app.datasource")
#Component
public class DataSourceConfig{
private String url;
private String username;
private String password;
...
}
Now, where you want to use the DataSourceConfig bean, you can inject like this,
#Autowired
DataSourceConfig dataSourceConfig;
And once you have the object just do,
dataSourceConfig.getUrl();
dataSourceConfig.getUsername();
dataSourceConfig.getPassword();