[Spring] @Value

@Value("${some.key:my default value}")
private String stringWithDefaultValue;

@Value("${some.key:})"
private String stringWithBlankDefaultValue;

@Value("${some.key:true}")
private boolean booleanWithDefaultValue;

@Value("${some.key:42}")
private int intWithDefaultValue;

@Value("${some.key:one,two,three}")
private String[] stringArrayWithDefaults;

@Value("${some.key:1,2,3}")
private int[] intArrayWithDefaults;

@Value("#{systemProperties['some.key'] ?: 'my default system property value'}")
private String spelWithDefaultValue;

https://www.baeldung.com/spring-value-defaults