Package groovy.lang

Class ProxyMetaClass

java.lang.Object
groovy.lang.MetaClassImpl
groovy.lang.ProxyMetaClass
All Implemented Interfaces:
AdaptingMetaClass, MetaClass, MetaObjectProtocol, MutableMetaClass
Direct Known Subclasses:
MockProxyMetaClass

public class ProxyMetaClass extends MetaClassImpl implements AdaptingMetaClass
As subclass of MetaClass, ProxyMetaClass manages calls from Groovy Objects to POJOs. It enriches MetaClass with the feature of making method invocations interceptable by an Interceptor. To this end, it acts as a decorator (decorator pattern) allowing to add or withdraw this feature at runtime. See groovy/lang/InterceptorTest.groovy for details.

WARNING: This implementation of ProxyMetaClass is NOT thread-safe and hence should only be used for as a per-instance MetaClass running in a single thread. Do not place this MetaClass in the MetaClassRegistry as it will result in unpredictable behaviour

See Also:
  • Field Details

  • Constructor Details

    • ProxyMetaClass

      public ProxyMetaClass(MetaClassRegistry registry, Class theClass, MetaClass adaptee)
      Parameters:
      adaptee - the MetaClass to decorate with interceptability
  • Method Details

    • getInstance

      public static ProxyMetaClass getInstance(Class theClass)
      convenience factory method for the most usual case.
    • initialize

      public void initialize()
      Description copied from class: MetaClassImpl
      Complete the initialisation process. After this method is called no methods should be added to the metaclass. Invocation of methods or access to fields/properties is forbidden unless this method is called. This method should contain any initialisation code, taking a longer time to complete. An example is the creation of the Reflector. It is suggested to synchronize this method.
      Specified by:
      initialize in interface MetaClass
      Overrides:
      initialize in class MetaClassImpl
    • getAdaptee

      public MetaClass getAdaptee()
      Description copied from interface: AdaptingMetaClass
      Returns the MetaClass that this adapter adapts
      Specified by:
      getAdaptee in interface AdaptingMetaClass
      Returns:
      The MetaClass instance
    • setAdaptee

      public void setAdaptee(MetaClass metaClass)
      Description copied from interface: AdaptingMetaClass
      Sets the MetaClass adapted by this MetaClass
      Specified by:
      setAdaptee in interface AdaptingMetaClass
      Parameters:
      metaClass - The MetaClass to adapt
    • getInterceptor

      public Interceptor getInterceptor()
      Returns:
      the interceptor in use or null if no interceptor is used
    • setInterceptor

      public void setInterceptor(Interceptor interceptor)
      Parameters:
      interceptor - may be null to reset any interception
    • use

      public Object use(Closure closure)
      Use the ProxyMetaClass for the given Closure. Cares for balanced register/unregister.
      Parameters:
      closure - piece of code to be executed with registered ProxyMetaClass
    • use

      public Object use(GroovyObject object, Closure closure)
      Use the ProxyMetaClass for the given Closure. Cares for balanced setting/unsetting ProxyMetaClass.
      Parameters:
      closure - piece of code to be executed with ProxyMetaClass
    • invokeMethod

      public Object invokeMethod(Object object, String methodName, Object[] arguments)
      Call invokeMethod on adaptee with logic like in MetaClass unless we have an Interceptor. With Interceptor the call is nested in its beforeInvoke and afterInvoke methods. The method call is suppressed if Interceptor.doInvoke() returns false. See Interceptor for details.
      Specified by:
      invokeMethod in interface MetaObjectProtocol
      Overrides:
      invokeMethod in class MetaClassImpl
      Parameters:
      object - The object which the method was invoked on
      methodName - The name of the method
      arguments - The arguments to the method
      Returns:
      The return value of the method
      See Also:
    • invokeMethod

      public Object invokeMethod(Class sender, Object object, String methodName, Object[] arguments, boolean isCallToSuper, boolean fromInsideClass)
      Call invokeMethod on adaptee with logic like in MetaClass unless we have an Interceptor. With Interceptor the call is nested in its beforeInvoke and afterInvoke methods. The method call is suppressed if Interceptor.doInvoke() returns false. See Interceptor for details.
      Specified by:
      invokeMethod in interface MetaClass
      Overrides:
      invokeMethod in class MetaClassImpl
      Parameters:
      sender - The java.lang.Class instance that invoked the method
      object - The object which the method was invoked on
      methodName - The name of the method
      arguments - The arguments to the method
      isCallToSuper - Whether the method is a call to a super class method
      fromInsideClass - Whether the call was invoked from the inside or the outside of the class
      Returns:
      The return value of the method
      See Also:
    • invokeStaticMethod

      public Object invokeStaticMethod(Object object, String methodName, Object[] arguments)
      Call invokeStaticMethod on adaptee with logic like in MetaClass unless we have an Interceptor. With Interceptor the call is nested in its beforeInvoke and afterInvoke methods. The method call is suppressed if Interceptor.doInvoke() returns false. See Interceptor for details.
      Specified by:
      invokeStaticMethod in interface MetaObjectProtocol
      Overrides:
      invokeStaticMethod in class MetaClassImpl
      Parameters:
      object - An instance of the class returned by the getTheClass() method or the class itself
      methodName - The name of the method
      arguments - The arguments to the method
      Returns:
      The return value of the method which is null if the return type is void
      See Also:
    • invokeConstructor

      public Object invokeConstructor(Object[] arguments)
      Call invokeConstructor on adaptee with logic like in MetaClass unless we have an Interceptor. With Interceptor the call is nested in its beforeInvoke and afterInvoke methods. The method call is suppressed if Interceptor.doInvoke() returns false. See Interceptor for details.
      Specified by:
      invokeConstructor in interface MetaObjectProtocol
      Overrides:
      invokeConstructor in class MetaClassImpl
      Parameters:
      arguments - The arguments to the constructor
      Returns:
      An instance of the java.lang.Class that this MetaObjectProtocol object applies to
    • getProperty

      public Object getProperty(Class aClass, Object object, String property, boolean useSuper, boolean fromInsideClass)
      Interceptors the call to getProperty if a PropertyAccessInterceptor is available
      Specified by:
      getProperty in interface MetaClass
      Overrides:
      getProperty in class MetaClassImpl
      Parameters:
      object - the object to invoke the getter on
      property - the property name
      aClass - The java.lang.Class instance that requested the property
      useSuper - Whether the call is to a super class property
      fromInsideClass - ??
      Returns:
      the value of the property
    • setProperty

      public void setProperty(Class aClass, Object object, String property, Object newValue, boolean useSuper, boolean fromInsideClass)
      Interceptors the call to a property setter if a PropertyAccessInterceptor is available
      Specified by:
      setProperty in interface MetaClass
      Overrides:
      setProperty in class MetaClassImpl
      Parameters:
      object - The object to invoke the setter on
      property - The property name to set
      newValue - The new value of the property
      aClass - The java.lang.Class instance that is mutating the property
      useSuper - Whether the call is to a super class property
      fromInsideClass - Whether the call was invoked from the inside or the outside of the class.