Package org.codehaus.groovy.reflection

Class CachedField

java.lang.Object
groovy.lang.MetaProperty
org.codehaus.groovy.reflection.CachedField
All Implemented Interfaces:
MetaMember
public class CachedField extends MetaProperty
Caches reflection information about a single field for efficient access and modification.

Extends MetaProperty to integrate with the meta-programming framework. Handles lazy field accessibility and provides property-like access to field values.

  • Constructor Details

    • CachedField

      public CachedField(Field field)
      Constructs a CachedField for the given Java field.
      Parameters:
      field - the field to cache reflection information for

  • Method Details

    • canAccessViaReflection

      public boolean canAccessViaReflection()
      Determines whether the reflective access path (Field.get/set) can reach this field: deep access has been, or can now be, established. The reflective path's callers use this to treat an unreachable field (strongly encapsulated declaring class) as absent instead of failing when it is read or written. It says nothing about what a caller's own Lookup may reach -- see asAccessMethod(MethodHandles.Lookup) -- and so must not be used to decide member selection or call-site linkage.
      Since:
      6.0.0

    • getCachedField

      public Field getCachedField()
      Returns the underlying Java Field object, making it accessible if necessary.
      Returns:
      the cached field with accessibility ensured

    • getDeclaringClass

      public Class getDeclaringClass()
      Returns the class that declares this field.
      Returns:
      the declaring class

    • isAnnotationPresent

      public boolean isAnnotationPresent(Class<? extends Annotation> annotationType)
      Checks whether the underlying field has the specified annotation. Unlike getCachedField(), this does not trigger accessibility changes.
      Since:
      6.0.0

    • getModifiers

      public int getModifiers()
      Returns the access modifiers.
      Specified by:
      getModifiers in interface MetaMember
      Overrides:
      getModifiers in class MetaProperty
      Returns:
      Modifier.PUBLIC

    • getProperty

      public Object getProperty(Object object)
      Specified by:
      getProperty in class MetaProperty
      Returns:
      the property of the given object

    • setProperty

      public void setProperty(Object object, Object newValue)
      Sets the property on the given object to the new value.
      Specified by:
      setProperty in class MetaProperty
      Parameters:
      object - on which to set the property
      newValue - the new value of the property

    • asAccessMethod

      public MethodHandle asAccessMethod(MethodHandles.Lookup lookup) throws IllegalAccessException
      Creates a method handle that provides getter access to this field via MethodHandles API. When deep-reflection access can be established (setAccessible on the field), the resulting handle is caller-independent and is created once and cached; otherwise the given caller lookup decides, and its handle -- which carries that caller's access rights -- is never cached.
      Parameters:
      lookup - the method handles lookup context of the caller
      Returns:
      a method handle providing getter access to this field
      Throws:
      IllegalAccessException - if neither deep reflection nor the caller's lookup can access the field

    • asWriteAccessMethod

      public MethodHandle asWriteAccessMethod(MethodHandles.Lookup lookup) throws IllegalAccessException
      Creates a method handle that writes this field via the MethodHandles API, the mutating counterpart of asAccessMethod(MethodHandles.Lookup), with the same caching policy. No deep-reflection handle is created for a final field: writing it must keep failing the caller's access check.
      Parameters:
      lookup - the method handles lookup context of the caller
      Returns:
      a setter handle of type (declaringClass, fieldType)void
      Throws:
      IllegalAccessException - if neither deep reflection nor the caller's lookup can write the field
      Since:
      6.0.0