annotations

问题 Consider the following class: private static class Widget { @JsonProperty private String id = "ID"; @JsonIgnore private String jsonIgnored = "JSON_IGNORED"; private String noAnnotation = "NO_ANNOTATION"; } If I serialize this using Jackson, I will end up with this string: {"id":"ID"} What is the difference between a property with @JsonIgnore and one with no annotation? 回答1: The @JsonIgnore annotated properties/methods will not be serialized/deserialized by Jackson. While the not annotated

问题 I'm currently adding annotations to my map through a loop... but the annotations are only appearing on my map in groups. Also, on load, only about 4 annotations are actually displayed on the map... but as I move the map a little, all of the annotations that should be there, suddenly appear. How can I get all of the annotations to load in the right place, one at a time? Thanks in advance! Here is the code I'm using to add annotations: NSString *incident; for (incident in weekFeed) { NSString

问题 I created enum Restrictions{ none, enumeration, fractionDigits, length, maxExclusive, maxInclusive, maxLength, minExclusive, minInclusive, minLength, pattern, totalDigits, whiteSpace; public Restrictions setValue(int value){ this.value = value; return this; } public int value; } So that I could happily do something like this, which is perfectly legal syntax. Restrictions r1 = Restrictions.maxLength.setValue(64); The reason being is, I am using enum to restrict the type of restriction that

问题 I am just looking to write some annotation which can execute at runtime, before or immediately after a service method is invoked. I don't know if they are executed at runtime or compile time. 回答1: Annotations don't execute; they're notes or markers that are read by various tools. Some are read by your compiler, like @Override ; others are embedded in the class files and read by tools like Hibernate at runtime. But they don't do anything themselves. You might be thinking of assertions instead,

问题 I'm trying to understand DI, but my spring bean is not injected or created when I use the autowire and component annotations. Instead I get a nullpointer exception because my bean is null. Should I created it manually and in that case where? Where do you specify the order in which the beans are created, when several beans depend on each other? Here is my code: App.java package se.springtest; import se.springtest.Person; import org.springframework.core.io.ClassPathResource; import org

问题 I have an annotation as: import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; @Target(ElementType.METHOD) @Retention(RetentionPolicy.RUNTIME) public @interface MyAnnotation { String annotationArgument1() default ""; String annotationArgument2(); } I have two classes as: class MyClass1 { @MyAnnotation(annotationArgument1="ABC", annotationArgument2="XYZ") public void method1(MyClass2

问题 I want to add multiple pins on a google map, while it is being loaded. I have a list of Latitude and Longitude values of nearby locations. How can I show all these locations on the map with a pin. I am using Google SDK for iOS. I am using the following code, but it didn't work for me. NSMutableArray *array = [NSMutableArray arrayWithObjects:@"12.981902,80.266333",@"12.982902,80.266363", nil]; CLLocationCoordinate2D pointsToUse[5]; for (int i = 0; i < [array Size]; i++) { pointsToUse[i] =

问题 I want to add multiple pins on a google map, while it is being loaded. I have a list of Latitude and Longitude values of nearby locations. How can I show all these locations on the map with a pin. I am using Google SDK for iOS. I am using the following code, but it didn't work for me. NSMutableArray *array = [NSMutableArray arrayWithObjects:@"12.981902,80.266333",@"12.982902,80.266363", nil]; CLLocationCoordinate2D pointsToUse[5]; for (int i = 0; i < [array Size]; i++) { pointsToUse[i] =

问题 I have a bean declared with annotation @Bean @Bean public Set<DefaultMessageListenerContainer> beans() { Set<DefaultMessageListenerContainer> containerSet = new HashSet<DefaultMessageListenerContainer>(); return containerSet; } I have some operations to be performed when I am destroying the bean. How can I achieve that? I know I can use @predestroy annotation on a method in a class annotated with @Component but not sure how can I do that when declared @Bean annotation. EDIT : @Bean

问题 I have a service method that tries to add an object with store() method of hibernate. get method is working for this DAO and service class whereas adding not working. In console there is no error. UrlWhiteListDaoImpl urlDao; MapperFacade mapper; @Autowired public UrlWhiteListingServiceImpl(UrlWhiteListDao urlWhiteListDao, MapperFacade mapper, UrlWhiteListDaoImpl urlDao) { this.urlDao = urlDao; this.urlWhiteListDao = urlWhiteListDao; this.mapper = mapper; } @Override public UrlWhiteListDto