org.jruby.internal.runtime.methods

Class NullMethod

java.lang.Object

org.jruby.internal.runtime.methods.DynamicMethod

org.jruby.internal.runtime.methods.NullMethod

public class NullMethod
extends DynamicMethod

This class represents a singleton type of method used as a marker for breaking method lookup loops. Like UndefinedMethod, only one instance is ever created, it can't be invoked, and shouldn't be returned as though it were a real method.

Nested Class Summary

Nested classes/interfaces inherited from class org.jruby.internal.runtime.methods.DynamicMethod

DynamicMethod.NativeCall

Field Summary

Fields

Modifier and Type	Field and Description
static NullMethod	INSTANCE

Fields inherited from class org.jruby.internal.runtime.methods.DynamicMethod

builtin, callConfig, handle, implementationClass, name, nativeCall, nativeCalls, notImplemented, protectedClass, serialNumber, visibility

Method Summary

Methods

Modifier and Type	Method and Description
IRubyObject	call(ThreadContext context, IRubyObject self, RubyModule klazz, String name, IRubyObject[] args, Block block) The one implementation of call, which throws an exception because NullMethod can't be invoked.
DynamicMethod	dup() A dummy implementation of dup that just returns the singleton instance.
static NullMethod	getInstance() Retrieve the singleton instance.
boolean	isCallableFrom(IRubyObject caller, CallType callType) NullMethod is always visible because it's only used as a marker to break method lookup loops.
void	setCallConfig(CallConfiguration callConfig) Dummy implementation of setCallConfig that does nothing.
void	setImplementationClass(RubyModule implClass) Dummy override of setImplementationClass that does nothing.
void	setVisibility(Visibility visibility) Dummy implementation of setVisibility that does nothing.

Methods inherited from class org.jruby.internal.runtime.methods.DynamicMethod

calculateProtectedClass, call, call, call, call, call, call, call, call, call, getArity, getCallConfig, getHandle, getImplementationClass, getMethodData, getName, getNativeCall, getNativeCall, getProtectedClass, getRealMethod, getSerialNumber, getVisibility, init, isBuiltin, isImplementedBy, isNative, isNotImplemented, isNull, isUndefined, setHandle, setIsBuiltin, setName, setNativeCall, setNativeCall, setNativeCall, setNotImplemented

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

INSTANCE

public static final NullMethod INSTANCE

Method Detail

call

public IRubyObject call(ThreadContext context,
               IRubyObject self,
               RubyModule klazz,
               String name,
               IRubyObject[] args,
               Block block)

The one implementation of call, which throws an exception because NullMethod can't be invoked.

Specified by:

call in class DynamicMethod

Parameters:

context - The thread context for the currently executing thread

self - The 'self' or 'receiver' object to use for this call

klazz - The Ruby class against which this method is binding

name - The incoming name used to invoke this method

args - The argument list to this invocation

block - The block passed to this invocation

Returns:

The result of the call

See Also:

DynamicMethod.call

dup

public DynamicMethod dup()

A dummy implementation of dup that just returns the singleton instance.

Specified by:

dup in class DynamicMethod

Returns:

The singleton instance

getInstance

public static NullMethod getInstance()

Retrieve the singleton instance.

Returns:

The singleton instance

setImplementationClass

public void setImplementationClass(RubyModule implClass)

Dummy override of setImplementationClass that does nothing.

Overrides:

setImplementationClass in class DynamicMethod

Parameters:

implClass - Ignored

setVisibility

public void setVisibility(Visibility visibility)

Dummy implementation of setVisibility that does nothing.

Overrides:

setVisibility in class DynamicMethod

Parameters:

visibility - Ignored

setCallConfig

public void setCallConfig(CallConfiguration callConfig)

Dummy implementation of setCallConfig that does nothing.

Overrides:

setCallConfig in class DynamicMethod

Parameters:

callConfig - Ignored

isCallableFrom

public boolean isCallableFrom(IRubyObject caller,
                     CallType callType)

NullMethod is always visible because it's only used as a marker to break method lookup loops.

Overrides:

isCallableFrom in class DynamicMethod

Parameters:

caller - The calling object

callType - The type of call

Returns:

true always