groovy.transform

Annotation Type ExternalizeMethods

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

Class annotation used to assist in the creation of Externalizable classes. The @ExternalizeMethods annotation instructs the compiler to execute an AST transformation which adds writeExternal() and readExternal() methods to a class and adds Externalizable to the interfaces which the class implements. The writeExternal() method writes each property (and optionally field) of the class while the readExternal() method will read each one back in the same order. Properties or fields marked as transient are ignored. This annotation is typically used in conjunction with the @ExternalizeMethods annotation but most usually not directly but rather via @AutoExternalizable which is a shortcut for both annotations.

Example usage:

 import groovy.transform.*
 @ExternalizeMethods
 class Person {
   String first, last
   List favItems
   Date since
 }
 

Which will create a class of the following form:

 class Person implements Externalizable {
   ...
   public void writeExternal(ObjectOutput out) throws IOException {
     out.writeObject(first)
     out.writeObject(last)
     out.writeObject(favItems)
     out.writeObject(since)
   }

   public void readExternal(ObjectInput oin) {
     first = (String) oin.readObject()
     last = (String) oin.readObject()
     favItems = (List) oin.readObject()
     since = (Date) oin.readObject()
   }
   ...
 }
 

Since:

1.8.0

Author:

Paul King

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element and Description
String[]	excludes Comma separated list of property names to exclude from externalizing.
boolean	includeFields Include fields as well as properties when externalizing.

Element Detail

excludes

public abstract String[] excludes

Comma separated list of property names to exclude from externalizing. For convenience, a String with comma separated names can be used in addition to an array (using Groovy's literal list notation) of String values.

Default:

{}

includeFields

public abstract boolean includeFields

Include fields as well as properties when externalizing.

Default:

false