groovy.lang
Annotation Type Lazy

@Retention(value=SOURCE)
@Target(value=FIELD)
public @interface Lazy

Field annotation to make field lazy initializable. If field declared volatile then initialization will be synchronized

 @Lazy volatile T x
 

becomes

 private volatile T $x

 T getX () {
   if ($x != null)
     return $x
   else {
     synchronized(this) {
        $x = new T ()
        return $x
     }
   }
 }
 

By default field will be initialized by call to default constructor If field has initial value expression then this expression will be used instead of default constructor. In particularly it is possible to use closures { ... } () syntax

 @Lazy T x = { [1,2,3] } ()
 

becomes

 private T $x

 T getX () {
   if ($x != null)
     return $x
   else {
     $x = { [1, 2, 3] } ()
     return $x
   }
 }
 

@Lazy(soft=true) will use soft reference instead of the field and use above rules each time re-initialization required

Author:

Alex Tkachman

Optional Element Summary

boolean

soft

soft

public abstract boolean soft

Returns:

if field should be soft referenced instead of hard referenced

Default:

false