Package groovy.lang

Class MetaClassImpl

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

public class MetaClassImpl extends Object implements MetaClass, MutableMetaClass
Allows methods to be dynamically added to existing classes at runtime
Version:
$Revision$
Author:
James Strachan, Guillaume Laforge, Jochen Theodorou, Graeme Rocher, Alex Tkachman, Roshan Dawrani
See Also:
  • Field Details

  • Constructor Details

  • Method Details

    • getTheCachedClass

      public final CachedClass getTheCachedClass()
    • respondsTo

      public List respondsTo(Object obj, String name, Object[] argTypes)
      Description copied from interface: MetaObjectProtocol

      Returns an object satisfying Groovy truth if the implementing MetaClass responds to a method with the given name and arguments types.

      Note that this method's return value is based on realised methods and does not take into account objects or classes that implement invokeMethod or methodMissing

      This method is "safe" in that it will always return a value and never throw an exception

      Specified by:
      respondsTo in interface MetaObjectProtocol
      Parameters:
      obj - The object to inspect
      name - The name of the method of interest
      argTypes - The argument types to match against
      Returns:
      A List of MetaMethods matching the argument types which will be empty if no matching methods exist
      See Also:
    • respondsTo

      public List respondsTo(Object obj, String name)
      Description copied from interface: MetaObjectProtocol

      Returns an object satisfying Groovy truth if the implementing MetaClass responds to a method with the given name regardless of arguments. In other words this method will return for foo() and foo(String).

      Note that this method's return value is based on realised methods and does not take into account objects or classes that implement invokeMethod or methodMissing

      This method is "safe" in that it will always return a value and never throw an exception

      Specified by:
      respondsTo in interface MetaObjectProtocol
      Parameters:
      obj - The object to inspect
      name - The name of the method of interest
      Returns:
      A List of MetaMethods which will be empty if no methods with the given name exist
      See Also:
    • hasProperty

      public MetaProperty hasProperty(Object obj, String name)
      Description copied from interface: MetaObjectProtocol

      Returns true of the implementing MetaClass has a property of the given name

      Note that this method will only return true for realised properties and does not take into account implementation of getProperty or propertyMissing

      Specified by:
      hasProperty in interface MetaObjectProtocol
      Parameters:
      obj - The object to inspect
      name - The name of the property
      Returns:
      The MetaProperty or null if it doesn't exist
      See Also:
    • getMetaProperty

      public MetaProperty getMetaProperty(String name)
      Description copied from interface: MetaObjectProtocol
      Returns a MetaProperty for the given name or null if it doesn't exist
      Specified by:
      getMetaProperty in interface MetaObjectProtocol
      Parameters:
      name - The name of the MetaProperty
      Returns:
      A MetaProperty or null
      See Also:
    • getStaticMetaMethod

      public MetaMethod getStaticMetaMethod(String name, Object[] argTypes)
      Description copied from interface: MetaObjectProtocol
      Retrieves a static MetaMethod for the given name and argument values, using the types of the arguments to establish the chosen MetaMethod
      Specified by:
      getStaticMetaMethod in interface MetaObjectProtocol
      Parameters:
      name - The name of the MetaMethod
      argTypes - The argument types
      Returns:
      A MetaMethod or null if it doesn't exist
      See Also:
    • getMetaMethod

      public MetaMethod getMetaMethod(String name, Object[] argTypes)
      Description copied from interface: MetaObjectProtocol
      Retrieves an instance MetaMethod for the given name and argument values, using the types of the argument values to establish the chosen MetaMethod
      Specified by:
      getMetaMethod in interface MetaObjectProtocol
      Parameters:
      name - The name of the MetaMethod
      argTypes - Array containing - 1) the argument values (using which their types are then inferred), or 2) the corresponding argument types
      Returns:
      A MetaMethod or null if it doesn't exist
      See Also:
    • getTheClass

      public Class getTheClass()
      Description copied from interface: MetaObjectProtocol
      Retrieves that Java Class that the attached Meta behaviours apply to
      Specified by:
      getTheClass in interface MetaObjectProtocol
      Returns:
      The java.lang.Class instance
    • isGroovyObject

      public boolean isGroovyObject()
    • getSuperClasses

      protected LinkedList<CachedClass> getSuperClasses()
    • isModified

      public boolean isModified()
      Description copied from interface: MutableMetaClass
      Return whether the MetaClass has been modified or not
      Specified by:
      isModified in interface MutableMetaClass
      Returns:
      True if it has
    • addNewInstanceMethod

      public void addNewInstanceMethod(Method method)
      Description copied from interface: MutableMetaClass
      adds a new instance method to this MetaClass. Instance methods are able to overwrite the original methods of the class. Calling this method should not be done after initialise was called.
      Specified by:
      addNewInstanceMethod in interface MutableMetaClass
      Parameters:
      method - the method to be added
    • addNewStaticMethod

      public void addNewStaticMethod(Method method)
      Description copied from interface: MutableMetaClass
      adds a new static method to this MetaClass. This is only possible as long as initialise was not called.
      Specified by:
      addNewStaticMethod in interface MutableMetaClass
      Parameters:
      method - the method to be added
    • invokeMethod

      public Object invokeMethod(Object object, String methodName, Object arguments)
      Description copied from interface: MetaObjectProtocol

      Invokes a method on the given object, with the given name and single argument.

      Specified by:
      invokeMethod in interface MetaObjectProtocol
      Parameters:
      object - The Object to invoke the method on
      methodName - The name of the method
      arguments - The argument to the method
      Returns:
      The return value of the method which is null if the return type is void
      See Also:
    • invokeMissingMethod

      public Object invokeMissingMethod(Object instance, String methodName, Object[] arguments)
      Description copied from interface: MetaClass

      Attempts to invoke the methodMissing method otherwise throws a MissingMethodException

      Specified by:
      invokeMissingMethod in interface MetaClass
      Parameters:
      instance - The instance to invoke methodMissing on
      methodName - The name of the method
      arguments - The arguments to the method
      Returns:
      The results of methodMissing or throws MissingMethodException
      See Also:
    • invokeMissingProperty

      public Object invokeMissingProperty(Object instance, String propertyName, Object optionalValue, boolean isGetter)
      Description copied from interface: MetaClass
      Invokes the propertyMissing method otherwise throws a MissingPropertyException
      Specified by:
      invokeMissingProperty in interface MetaClass
      Parameters:
      instance - The instance of the class
      propertyName - The name of the property
      optionalValue - The value of the property which could be null in the case of a getter
      isGetter - Whether the missing property event was the result of a getter or a setter
      Returns:
      The result of the propertyMissing method or throws MissingPropertyException
    • onSuperPropertyFoundInHierarchy

      protected void onSuperPropertyFoundInHierarchy(MetaBeanProperty property)
    • onMixinMethodFound

      protected void onMixinMethodFound(MetaMethod method)
    • onSuperMethodFoundInHierarchy

      protected void onSuperMethodFoundInHierarchy(MetaMethod method)
    • onInvokeMethodFoundInHierarchy

      protected void onInvokeMethodFoundInHierarchy(MetaMethod method)
    • onSetPropertyFoundInHierarchy

      protected void onSetPropertyFoundInHierarchy(MetaMethod method)
    • onGetPropertyFoundInHierarchy

      protected void onGetPropertyFoundInHierarchy(MetaMethod method)
    • invokeStaticMissingProperty

      protected Object invokeStaticMissingProperty(Object instance, String propertyName, Object optionalValue, boolean isGetter)
      Hook to deal with the case of MissingProperty for static properties. The method will look attempt to look up "propertyMissing" handlers and invoke them otherwise thrown a MissingPropertyException
      Parameters:
      instance - The instance
      propertyName - The name of the property
      optionalValue - The value in the case of a setter
      isGetter - True if its a getter
      Returns:
      The value in the case of a getter or a MissingPropertyException
    • invokeMethod

      public Object invokeMethod(Object object, String methodName, Object[] originalArguments)
      Invokes the given method on the object. TODO: should this be deprecated? If so, we have to propogate to many places.
      Specified by:
      invokeMethod in interface MetaObjectProtocol
      Parameters:
      object - The instance which the method is invoked on
      methodName - The name of the method
      originalArguments - The arguments to the method
      Returns:
      The return value of the method which is null if the return type is void
      See Also:
    • invokeMethod

      public Object invokeMethod(Class sender, Object object, String methodName, Object[] originalArguments, boolean isCallToSuper, boolean fromInsideClass)
      Invokes the given method on the object.
      Specified by:
      invokeMethod in interface MetaClass
      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
      originalArguments - 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
    • getMethodWithCaching

      public MetaMethod getMethodWithCaching(Class sender, String methodName, Object[] arguments, boolean isCallToSuper)
    • retrieveConstructor

      public Constructor retrieveConstructor(Class[] arguments)
    • retrieveStaticMethod

      public MetaMethod retrieveStaticMethod(String methodName, Object[] arguments)
    • getMethodWithoutCaching

      public MetaMethod getMethodWithoutCaching(Class sender, String methodName, Class[] arguments, boolean isCallToSuper)
    • invokeStaticMethod

      public Object invokeStaticMethod(Object object, String methodName, Object[] arguments)
      Description copied from interface: MetaObjectProtocol

      Invokes a static method on the given Object with the given name and arguments.

      The Object can either be an instance of the class that this MetaObjectProtocol instance applies to or the java.lang.Class instance itself. If a method cannot be invoked a MissingMethodException is will be thrown

      Specified by:
      invokeStaticMethod in interface MetaObjectProtocol
      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:
    • invokeConstructorAt

      public Object invokeConstructorAt(Class at, Object[] arguments)
      Deprecated.
      use invokeConstructor instead
      Warning, this method will be removed
    • invokeConstructor

      public Object invokeConstructor(Object[] arguments)
      Description copied from interface: MetaObjectProtocol
      Invokes a constructor for the given arguments. The MetaClass will attempt to pick the best argument which matches the types of the objects passed within the arguments array
      Specified by:
      invokeConstructor in interface MetaObjectProtocol
      Parameters:
      arguments - The arguments to the constructor
      Returns:
      An instance of the java.lang.Class that this MetaObjectProtocol object applies to
    • selectConstructorAndTransformArguments

      public int selectConstructorAndTransformArguments(int numberOfConstructors, Object[] arguments)
      Description copied from interface: MetaClass
      Internal method to support Groovy runtime. Not for client usage.
      Specified by:
      selectConstructorAndTransformArguments in interface MetaClass
      Parameters:
      numberOfConstructors - The number of constructors
      arguments - The arguments
      Returns:
      selected index
    • checkInitalised

      protected void checkInitalised()
      checks if the initialisation of the class id complete. This method should be called as a form of assert, it is no way to test if there is still initialisation work to be done. Such logic must be implemented in a different way.
      Throws:
      IllegalStateException - if the initialisation is incomplete yet
    • setProperties

      public void setProperties(Object bean, Map map)
      Sets a number of bean properties from the given Map where the keys are the String names of properties and the values are the values of the properties to set
    • getProperty

      public Object getProperty(Class sender, Object object, String name, boolean useSuper, boolean fromInsideClass)
      Description copied from interface: MetaClass

      Retrieves a property on the given receiver for the specified arguments. The sender is the class that is requesting the property from the object. The MetaClass will attempt to establish the method to invoke based on the name and arguments provided.

      The isCallToSuper and fromInsideClass help the Groovy runtime perform optimisations on the call to go directly to the super class if necessary

      Specified by:
      getProperty in interface MetaClass
      Parameters:
      sender - The java.lang.Class instance that requested the property
      object - The Object which the property is being retrieved from
      name - The name of the property
      useSuper - Whether the call is to a super class property
      fromInsideClass - ??
      Returns:
      the given property's value on the object
    • getEffectiveGetMetaProperty

      public MetaProperty getEffectiveGetMetaProperty(Class sender, Object object, String name, boolean useSuper)
    • getProperties

      public List<MetaProperty> getProperties()
      Get all the properties defined for this type
      Specified by:
      getProperties in interface MetaClass
      Specified by:
      getProperties in interface MetaObjectProtocol
      Returns:
      a list of MetaProperty objects
      See Also:
    • applyPropertyDescriptors

      protected void applyPropertyDescriptors(PropertyDescriptor[] propertyDescriptors)
    • addMetaBeanProperty

      public void addMetaBeanProperty(MetaBeanProperty mp)
      Adds a new MetaBeanProperty to this MetaClass
      Specified by:
      addMetaBeanProperty in interface MutableMetaClass
      Parameters:
      mp - The MetaBeanProperty
    • setProperty

      public void setProperty(Class sender, Object object, String name, Object newValue, boolean useSuper, boolean fromInsideClass)
      Sets the property value on an object
      Specified by:
      setProperty in interface MetaClass
      Parameters:
      sender - The java.lang.Class instance that is mutating the property
      object - The Object which the property is being set on
      name - The name of the property
      newValue - The new value of the property to set
      useSuper - Whether the call is to a super class property
      fromInsideClass - ??
    • getAttribute

      public Object getAttribute(Class sender, Object receiver, String messageName, boolean useSuper)
      Description copied from interface: MetaClass
      Retrieves the value of an attribute (field). This method is to support the Groovy runtime and not for general client API usage.
      Specified by:
      getAttribute in interface MetaClass
      Parameters:
      sender - The class of the object that requested the attribute
      receiver - The instance
      messageName - The name of the attribute
      useSuper - Whether to look-up on the super class or not
      Returns:
      The attribute value
    • getAttribute

      public Object getAttribute(Class sender, Object object, String attribute, boolean useSuper, boolean fromInsideClass)
      Looks up the given attribute (field) on the given object
    • setAttribute

      public void setAttribute(Class sender, Object object, String attribute, Object newValue, boolean useSuper, boolean fromInsideClass)
      Sets the given attribute (field) on the given object
      Specified by:
      setAttribute in interface MetaClass
      Parameters:
      sender - The class of the object that requested the attribute
      object - The instance
      attribute - The name of the attribute
      newValue - The value of the attribute
      useSuper - Whether to look-up on the super class or not
      fromInsideClass - Whether the call happened from the inside or the outside of a class
    • getClassNode

      public ClassNode getClassNode()
      Description copied from interface: MetaClass
      Obtains a reference to the original AST for the MetaClass if it is available at runtime
      Specified by:
      getClassNode in interface MetaClass
      Returns:
      The original AST or null if it cannot be returned
    • toString

      public String toString()
      Overrides:
      toString in class Object
    • addMetaMethod

      public void addMetaMethod(MetaMethod method)
      adds a MetaMethod to this class. WARNING: this method will not do the neccessary steps for multimethod logic and using this method doesn't mean, that a method added here is replacing another method from a parent class completely. These steps are usually done by initialize, which means if you need these steps, you have to add the method before running initialize the first time.
      Specified by:
      addMetaMethod in interface MutableMetaClass
      Parameters:
      method - the MetaMethod
      See Also:
    • addMetaMethodToIndex

      protected void addMetaMethodToIndex(MetaMethod method, MetaMethodIndex.Header header)
    • checkIfGroovyObjectMethod

      protected final void checkIfGroovyObjectMethod(MetaMethod metaMethod)
      Checks if the metaMethod is a method from the GroovyObject interface such as setProperty, getProperty and invokeMethod
      Parameters:
      metaMethod - The metaMethod instance
      See Also:
    • isInitialized

      protected boolean isInitialized()
    • chooseMethod

      protected Object chooseMethod(String methodName, Object methodOrList, Class[] arguments)
      Chooses the correct method to use from a list of methods which match by name.
      Parameters:
      methodOrList - the possible methods to choose from
      arguments -
    • initialize

      public void initialize()
      Description copied from interface: MetaClass
      complete the initialisation process. After this method is called no methods should be added to the meta class. 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
    • getMethods

      public List<MetaMethod> getMethods()
      Description copied from interface: MetaClass
      Retrieves a list of MetaMethods held by the class
      Specified by:
      getMethods in interface MetaClass
      Specified by:
      getMethods in interface MetaObjectProtocol
      Returns:
      A list of MetaMethods
      See Also:
    • getMetaMethods

      public List<MetaMethod> getMetaMethods()
      Description copied from interface: MetaClass
      Retrieves a list of MetaMethods held by this class
      Specified by:
      getMetaMethods in interface MetaClass
      Returns:
      A list of MetaMethods
    • dropStaticMethodCache

      protected void dropStaticMethodCache(String name)
    • dropMethodCache

      protected void dropMethodCache(String name)
    • createPojoCallSite

      public CallSite createPojoCallSite(CallSite site, Object receiver, Object[] args)
    • createStaticSite

      public CallSite createStaticSite(CallSite site, Object[] args)
    • createPogoCallSite

      public CallSite createPogoCallSite(CallSite site, Object[] args)
    • createPogoCallCurrentSite

      public CallSite createPogoCallCurrentSite(CallSite site, Class sender, Object[] args)
    • createConstructorSite

      public CallSite createConstructorSite(CallSite site, Object[] args)
    • getClassInfo

      public ClassInfo getClassInfo()
    • getVersion

      public int getVersion()
    • incVersion

      public void incVersion()
    • getAdditionalMetaMethods

      public MetaMethod[] getAdditionalMetaMethods()
    • findPropertyInClassHierarchy

      protected MetaBeanProperty findPropertyInClassHierarchy(String propertyName, CachedClass theClass)
    • findMixinMethod

      protected MetaMethod findMixinMethod(String methodName, Class[] arguments)
    • findMethodInClassHierarchy

      protected static MetaMethod findMethodInClassHierarchy(Class instanceKlazz, String methodName, Class[] arguments, MetaClass metaClass)
    • findOwnMethod

      protected static MetaMethod findOwnMethod(Class instanceKlazz, String methodName, Class[] arguments, MetaClass metaClass, MetaMethod method)
    • getSubclassMetaMethods

      protected Object getSubclassMetaMethods(String methodName)
    • getProperty

      public Object getProperty(Object object, String property)
      Description copied from interface: MetaObjectProtocol

      Retrieves a property of an instance of the class returned by the getTheClass() method.

      What this means is largely down to the MetaClass implementation, however the default case would result in an attempt to invoke a JavaBean getter, or if no such getter exists a public field of the instance.

      Specified by:
      getProperty in interface MetaObjectProtocol
      Parameters:
      object - An instance of the class returned by the getTheClass() method
      property - The name of the property to retrieve the value for
      Returns:
      The properties value
      See Also:
    • setProperty

      public void setProperty(Object object, String property, Object newValue)
      Description copied from interface: MetaObjectProtocol

      Sets a property of an instance of the class returned by the getTheClass() method.

      What this means is largely down to the MetaClass implementation, however the default case would result in an attempt to invoke a JavaBean setter, or if no such setter exists to set a public field of the instance.

      Specified by:
      setProperty in interface MetaObjectProtocol
      Parameters:
      object - An instance of the class returned by the getTheClass() method
      property - The name of the property to set
      newValue - The new value of the property
      See Also:
    • getAttribute

      public Object getAttribute(Object object, String attribute)
      Description copied from interface: MetaObjectProtocol

      Retrieves an attribute of an instance of the class returned by the getTheClass() method.

      What this means is largely down to the MetaClass implementation, however the default case would result in attempt to read a field of the instance.

      Specified by:
      getAttribute in interface MetaObjectProtocol
      Parameters:
      object - An instance of the class returned by the getTheClass() method
      attribute - The name of the attribute to retrieve the value for
      Returns:
      The attribute value
      See Also:
    • setAttribute

      public void setAttribute(Object object, String attribute, Object newValue)
      Description copied from interface: MetaObjectProtocol

      Sets an attribute of an instance of the class returned by the getTheClass() method.

      What this means is largely down to the MetaClass implementation, however the default case would result in an attempt to set a field of the instance.

      Specified by:
      setAttribute in interface MetaObjectProtocol
      Parameters:
      object - An instance of the class returned by the getTheClass() method
      attribute - The name of the attribute to set
      newValue - The new value of the attribute
      See Also:
    • pickMethod

      public MetaMethod pickMethod(String methodName, Class[] arguments)
      Description copied from interface: MetaClass
      Selects a method by name and argument classes. This method does not search for an exact match, it searches for a compatible method. For this the method selection mechanism is used as provided by the implementation of this MetaClass. pickMethod may or may not be used during the method selection process when invoking a method. There is no warranty for that.
      Specified by:
      pickMethod in interface MetaClass
      Parameters:
      methodName - the name of the method to pick
      arguments - the method arguments
      Returns:
      a matching MetaMethod or null
    • retrieveMethod

      protected MetaMethod retrieveMethod(String methodName, Class[] arguments)
      Deprecated.
      use pickMethod instead
    • clearInvocationCaches

      protected void clearInvocationCaches()
      remove all method call cache entries. This should be done if a method is added during runtime, but not by using a category.