SpringBoot @ConfigurationProperties使用详解

<parent>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-parent</artifactId>
  <relativePath/> <!-- lookup parent from repository -->
</parent>

@Data
@Configuration
@ConfigurationProperties(prefix = "mail")
public class ConfigProperties {

  private String hostName;
  private int port;
  private String from;
}

#Simple properties
mail.hostname=host@mail.com
mail.port=9000
mail.from=mailer@mail.com

mail.hostName
mail.hostname
mail.host_name
mail.host-name
mail.HOST_NAME

@SpringBootApplication
@EnableConfigurationProperties(ConfigProperties.class)
public class ConfigPropApp {
  public static void main(String[] args) {
    SpringApplication.run(ConfigPropApp.class,args);
  }
}

@SpringBootApplication
@ConfigurationPropertiesScan("com.flydean.config")
public class ConfigPropApp {
  public static void main(String[] args) {
    SpringApplication.run(ConfigPropApp.class,args);
  }
}

@Data
public class Credentials {
  private String authMethod;
  private String username;
  private String password;
}

@Data
@Configuration
@ConfigurationProperties(prefix = "nestmail")
public class NestConfigProperties {
  private String host;
  private int port;
  private String from;
  private List<String> defaultRecipients;
  private Map<String, String> additionalHeaders;
  private Credentials credentials;
}

# nest Simple properties
nestmail.hostname=mailer@mail.com
nestmail.port=9000
nestmail.from=mailer@mail.com

#List properties
nestmail.defaultRecipients[0]=admin@mail.com
nestmail.defaultRecipients[1]=owner@mail.com

#Map Properties
nestmail.additionalHeaders.redelivery=true
nestmail.additionalHeaders.secure=true

#Object properties
nestmail.credentials.username=john
nestmail.credentials.password=password
nestmail.credentials.authMethod=SHA1

@Data
public class Item {
  private String name;
  private int size;
}

@Data
@Configuration
public class BeanConfigProperties {
  @Bean
  @ConfigurationProperties(prefix = "item")
  public Item item() {
    return new Item();
  }
}

@Data
@Validated
@Configuration
@ConfigurationProperties(prefix = "mail")
public class ConfigProperties {

  @NotEmpty
  private String hostName;
  @Min(1025)
  @Max(65536)
  private int port;
  @Pattern(regexp = "^[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,6}$")
  private String from;
}

Binding to target org.springframework.boot.context.properties.bind.BindException: Failed to bind properties under 'mail' to com.flydean.config.ConfigProperties$$EnhancerBySpringCGLIB$$f0f87cb9 failed:

  Property: mail.port
  Value: 0
  Reason: 最小不能小于1025

  Property: mail.hostName
  Value: null
  Reason: 不能为空


Action:

Update your application's configuration


Process finished with exit code 1

@ConfigurationProperties(prefix = "conversion")
public class PropertyConversion {
 
  private Duration timeInDefaultUnit;
  private Duration timeInNano;
  ...
}

conversion.timeInDefaultUnit=10
conversion.timeInNano=9ns

@DurationUnit(ChronoUnit.DAYS)
private Duration timeInDays;

conversion.timeInDays=2

private DataSize sizeInDefaultUnit;
 
private DataSize sizeInGB;
 
@DataSizeUnit(DataUnit.TERABYTES)
private DataSize sizeInTB;

conversion.sizeInDefaultUnit=300
conversion.sizeInGB=2GB
conversion.sizeInTB=4

public class Employee {
  private String name;
  private double salary;
}

conversion.employee=john,2000

@Component
@ConfigurationPropertiesBinding
public class EmployeeConverter implements Converter<String, Employee> {
 
  @Override
  public Employee convert(String from) {
    String[] data = from.split(",");
    return new Employee(data[0], Double.parseDouble(data[1]));
  }
}