annotations

问题 public Class User { private String name; private Integer age; ... } ObjectMapper om = new ObjectMapper(); om.writeValueAsString(user); How can I filter properties without using any annotations like @JsonIgnore? 回答1: You have two possible ways using Jackson Mixin Annotations :- http://www.cowtowncoder.com/blog/archives/2009/08/entry_305.html JSON Filter :- http://wiki.fasterxml.com/JacksonFeatureJsonFilter 回答2: The example of excluding properties by name: public Class User { private String

问题 I have an Rss feed that I'd like to parse in Java using Simple Framework. I have problems with 2 elements with the same name, but one of them has a namespace assigned. Here is an example xml: <?xml version="1.0" encoding="UTF-8"?> <rss xmlns:dc="http://purl.org/dc/elements/1.1/"> <item> <title>Regular Titel</title> <dc:title>Dc Titel</dc:title> </item> </rss> Currently my Item.class looks like this: @Root public class Item { @Namespace(reference = "http://purl.org/dc/elements/1.1/", prefix =

问题 I've been searching for the answer to "how to add an annotation to the method at runtime" for several days already and found this awesome tool called Byte Buddy, played with it, but still cannot make it work as I need to. I'm sure it must be able to do that from this question Can Byte Buddy create fields and method annotations at runtime? Having this class: public class ClassThatNeedsToBeAnnotated { public void method(int arg1, String arg2) { // code that we don't want to touch at all, leave

问题 I've been searching for the answer to "how to add an annotation to the method at runtime" for several days already and found this awesome tool called Byte Buddy, played with it, but still cannot make it work as I need to. I'm sure it must be able to do that from this question Can Byte Buddy create fields and method annotations at runtime? Having this class: public class ClassThatNeedsToBeAnnotated { public void method(int arg1, String arg2) { // code that we don't want to touch at all, leave

问题 In my view, i've nav bar at the top and remaining view is filled with map view. My Map view has pins and on click of pin, it will show annotations also. In the top right nav bar i've a button and on click of it, i want to remove the annotation view that popped up. (what ever annotation view is there, i want to remove from the view). Can some one tell me how to do it. The simple task we can do is to send some touch event to the map view which will hide it..... am i right. how to do it? 回答1: To

问题 Here is my code: Const.kt package sample.com.sample_app object Const { const val NAVIGATION_MODE_STANDARD = 1 const val NAVIGATION_MODE_LIST = 2 } NavigationMode.kt package sample.com.sample_app import android.support.annotation.IntDef import java.lang.annotation.Retention import java.lang.annotation.RetentionPolicy.SOURCE @Retention(SOURCE) @IntDef(Const.NAVIGATION_MODE_LIST, Const.NAVIGATION_MODE_STANDARD) annotation class NavigationMode OtherAct.kt package sample.com.sample_app import

问题 I've got a problem creating a simple ManyToMany mapping with hibernate anotations. Table PAGE has a composite primary key. +==============+ +================+ +==============+ | PAGE | | PAGE_USER | | USER | +--------------+ 1 0..* +----------------+ 0..* 1 +--------------+ | pageid (pk) |-----------| pageid (pk) |----------| userid (pk) | | entityid (pk)| | entityid (pk) | | ... | | ... | | userid (pk) | | | +==============+ +================+ +==============+ I solved the composite primary

问题 In my auditable entities I have field creationUser which I would like to not update in db on merge operation. Here is my entity code: @Column(updatable=false) @ManyToOne(cascade = CascadeType.MERGE) public User creationUser; But it gives me an error: Unexpected exception PersistenceException: [PersistenceUnit: defaultPersistenceUnit] Unable to build EntityManagerFactory Caused by: org.hibernate.AnnotationException: @Column(s) not allowed on a @ManyToOne property: models.AreaOfMedicine

问题 Checkstyle warns when I have a public method without javadoc, which is nice! When I override a public method I don't get the warning because the javadoc is already available in the parent class for the method. Now I have an other annotation for my method for example @MyEvent . Now I do get the warning but don't want it because the annotation says enough. Can I exclude warnings for methods with a specific annotation? There are some solutions that involve adding stuff to my code like

问题 I have drawn a trajectory plot in python using matplotlib of a boat like so: Now I want to add some arrows, like wind direction, true heading etc. However I want the arrows to have the same size no matter which zoom-level the plot is at. I tried matplotlib.pyplot.arrow, however there I have to define the length of the arrows. I could make matplotlib.pyplot.arrow work, but then I'd have to get the height and width of the plot, and scale my arrows accordingly, so I wondered if there was a