jsinterop.annotations

Annotation Type JsType

@Retention(value=RUNTIME)
 @Target(value=TYPE)
 @Documented
public @interface JsType

JsType is used to describe the JavaScript API of an object, either one that already exists from the external JavaScript environment, or one that will be accessible from the external JavaScript environment.

Marking an object with JsType is similar to marking each public member of the class with JsProperty/JsMethod/JsConstructor respectively. In order for this to work correctly the JavaScript name needs to be unique for each member. Some unobvious ways to cause name collisions are:

• having method or constructor overloads
• using the same name for a method and a field
• shadowing a field from parent

Name collisions must be avoided by providing custom names (e.g. JsProperty.name()) or by ignoring members using JsIgnore.

If the JsType is marked as "native" via isNative(), then the type is considered a stub for an existing class that is available in native JavaScript. Unlike non-native JsTypes, all members are considered JsProperty/JsMethod/JsConstructor unless they are explicitly marked with JsOverlay.

For native interfaces with no particular JavaScript type associated with them (e.g. structural types) it is recommeded to use namespace = JsPackage.GLOBAL and name = '?'.

Instanceof and Castability:

If the JsType is native, the generated code will try to mimic Javascript semantics.

All non-native JsTypes will follow regular Java semantics in terms of castability.

• For concrete native JsTypes, cast checks and instanceof checks will be delegated to the native JavaScript instanceof operator.
• For interface native JsTypes, instanceof is forbidden and casts to them always succeed.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
boolean	isNative Set to true, this JsType is a native JavaScript type.
java.lang.String	name Customizes the name of the type in generated JavaScript.
java.lang.String	namespace Customizes the namespace of the type in generated JavaScript.

Element Detail

name

public abstract java.lang.String name

Customizes the name of the type in generated JavaScript. If not provided, the simple Java name will be used.

Default:

"<auto>"

namespace

public abstract java.lang.String namespace

Customizes the namespace of the type in generated JavaScript.

Default:

"<auto>"

isNative

public abstract boolean isNative

Set to true, this JsType is a native JavaScript type.

Default:

false