## groovy.lang
Interface ProxyMetaClass

As subclass of MetaClass, ProxyMetaClass manages calls from Groovy Objects to POJOs. It enriches MetaClass with the feature of making method invokations 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 threadsafe 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

author:
  Dierk Koenig

author:
  Graeme Rocher

see:
  MetaClassRegistry

Field Summary
`MetaClass` | `adaptee`
`Interceptor` | `interceptor`

Constructor Summary
`ProxyMetaClass(MetaClassRegistry registry, Class theClass, MetaClass adaptee)`

Method Summary
`Object` | `call()`
`Object` | `doCall(Object object, String methodName, def arguments, Interceptor interceptor, Callable howToInvoke)`
`MetaClass` | `getAdaptee()`
`static ProxyMetaClass` | `getInstance(Class theClass)` convenience factory method for the most usual case.
`Interceptor` | `getInterceptor()`
`Object` | `getProperty(Class aClass, Object object, String property, boolean b, boolean b1)` Interceptors the call to getProperty if a PropertyAccessInterceptor is available
`void` | `initialize()`
`Object` | `invokeConstructor(def arguments)` Call invokeConstructor on adaptee with logic like in MetaClass unless we have an Interceptor.
`Object` | `invokeMethod(Object object, String methodName, def arguments)` Call invokeMethod on adaptee with logic like in MetaClass unless we have an Interceptor.
`Object` | `invokeStaticMethod(Object object, String methodName, def arguments)` Call invokeStaticMethod on adaptee with logic like in MetaClass unless we have an Interceptor.
`void` | `setAdaptee(MetaClass metaClass)`
`void` | `setInterceptor(Interceptor interceptor)`
`void` | `setProperty(Class aClass, Object object, String property, Object newValue, boolean b, boolean b1)` Interceptors the call to a property setter if a PropertyAccessInterceptor is available
`void` | `use(Closure closure)` Use the ProxyMetaClass for the given Closure.
`void` | `use(GroovyObject object, Closure closure)` Use the ProxyMetaClass for the given Closure.

Constructor Detail

### ProxyMetaClass

    public ProxyMetaClass(MetaClassRegistry registry, Class theClass, MetaClass adaptee)

  param:
    adaptee the MetaClass to decorate with interceptability

Method Detail

### call

    public Object call()

### doCall

    Object doCall(Object object, String methodName, def arguments, Interceptor interceptor, Callable howToInvoke)

### getAdaptee

    public MetaClass getAdaptee()

### getInstance

    public static ProxyMetaClass getInstance(Class theClass)

  convenience factory method for the most usual case.

### getInterceptor

    public Interceptor getInterceptor()

  return:
    the interceptor in use or null if no interceptor is used

### getProperty

    public Object getProperty(Class aClass, Object object, String property, boolean b, boolean b1)

  Interceptors the call to getProperty if a PropertyAccessInterceptor is available
  param:
    object the object to invoke the getter on
  param:
    property the property name
  return:
    the value of the property

### initialize

    public void initialize()

### invokeConstructor

    public Object invokeConstructor(def 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.

### invokeMethod

    public Object invokeMethod(Object object, String methodName, def 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.

### invokeStaticMethod

    public Object invokeStaticMethod(Object object, String methodName, def 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.

### setAdaptee

    public void setAdaptee(MetaClass metaClass)

### setInterceptor

    public void setInterceptor(Interceptor interceptor)

  param:
    interceptor may be null to reset any interception

### setProperty

    public void setProperty(Class aClass, Object object, String property, Object newValue, boolean b, boolean b1)

  Interceptors the call to a property setter if a PropertyAccessInterceptor is available
  param:
    object The object to invoke the setter on
  param:
    property The property name to set
  param:
    newValue The new value of the property

### use

    public void use(Closure closure)

  Use the ProxyMetaClass for the given Closure. Cares for balanced register/unregister.
  param:
    closure piece of code to be executed with registered ProxyMetaClass

### use

    public void use(GroovyObject object, Closure closure)

  Use the ProxyMetaClass for the given Closure. Cares for balanced setting/unsetting ProxyMetaClass.
  param:
    closure piece of code to be executed with ProxyMetaClass