org.apache.harmony.kernel.vm.Objects Class Reference

List of all members.

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Detailed Description

This class must be implemented by the VM to support Object manipulation.

Public Member Functions
long	getFieldOffset (Field field)
int	getArrayBaseOffset (Class<?> clazz)
int	getArrayIndexScale (Class<?> clazz)
boolean	compareAndSwapInt (Object object, long fieldOffset, int expected, int update)
boolean	compareAndSwapLong (Object object, long fieldOffset, long expected, long update)
boolean	compareAndSwapObject (Object object, long fieldOffset, Object expected, Object update)
void	putIntVolatile (Object object, long fieldOffset, int newValue)
int	getIntVolatile (Object object, long fieldOffset)
void	putLongVolatile (Object object, long fieldOffset, long newValue)
long	getLongVolatile (Object object, long fieldOffset)
void	putObjectVolatile (Object object, long fieldOffset, Object newValue)
Object	getObjectVolatile (Object object, long fieldOffset)
void	putLong (Object object, long fieldOffset, long newValue)
long	getLong (Object object, long fieldOffset)
Static Public Member Functions
static Objects	getInstance ()
Static Private Attributes
static final Objects	INSTANCE = new Objects()

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Member Function Documentation

static Objects org.apache.harmony.kernel.vm.Objects.getInstance

(

)

[static]

Retrieves an instance of the Objects service.

Returns:

An instance of Objects.

long org.apache.harmony.kernel.vm.Objects.getFieldOffset

(

Field

field

)

Retrieves the offset value of the Field for use by other methods in this class.

Parameters:

field

The Field to retrieve the offset for.

Returns:

The offset value.

int org.apache.harmony.kernel.vm.Objects.getArrayBaseOffset

(

Class<?>

clazz

)

Retrieves the base offset for the array Class given. The Class passed MUST me an array type, such that the method Class#isArray() returns true. For example, int[].class.

Parameters:

clazz

The array Class object.

Returns:

The base offset value.

Exceptions:

	NullPointerException	if clazz is null.
	IllegalArgumentException	if clazz is not an array type.

int org.apache.harmony.kernel.vm.Objects.getArrayIndexScale

(

Class<?>

clazz

)

Retrieves the array index scale for the array Class given. The index scale is the value used to determine the offset of a particular element in the array given the array's base offset and an index. The following code snippet illustrates the usage.

 int base = Objects.getArrayBaseOffset(int[].class);

 int scale = Objects.getArrayIndexScale(int[].class);

 int elementIdx = 1;

 int[] array = { 0, 1, 2 };

 long offsetForIdx = base + (elementIdx * scale);
 

The Class passed MUST me an array type, such that the method Class#isArray() returns true. For example, int[].class.

Parameters:

clazz

The array Class object.

Returns:

The index scale value.

Exceptions:

	NullPointerException	if clazz is null.
	IllegalArgumentException	if clazz is not an array type.

boolean org.apache.harmony.kernel.vm.Objects.compareAndSwapInt	(	Object	object,
		long	fieldOffset,
		int	expected,
		int	update
	)

Compares and swaps the value of an int-typed field on an Object instance.

Parameters:

	object	The instance containing the field.
	fieldOffset	The offset value of the field.
	expected	The expected value of the field.
	update	The new value to write to the field.

Returns:

true if the field was updated, false otherwise.

boolean org.apache.harmony.kernel.vm.Objects.compareAndSwapLong	(	Object	object,
		long	fieldOffset,
		long	expected,
		long	update
	)

Compares and swaps the value of a long-typed field on an Object instance.

Parameters:

	object	The instance containing the field.
	fieldOffset	The offset value of the field.
	expected	The expected value of the field.
	update	The new value to write to the field.

Returns:

true if the field was updated, false otherwise.

boolean org.apache.harmony.kernel.vm.Objects.compareAndSwapObject	(	Object	object,
		long	fieldOffset,
		Object	expected,
		Object	update
	)

Compares and swaps the value of an Object-typed field on an Object instance.

Parameters:

	object	The instance containing the field.
	fieldOffset	The offset value of the field.
	expected	The expected value of the field.
	update	The new value to write to the field.

Returns:

true if the field was updated, false otherwise.

void org.apache.harmony.kernel.vm.Objects.putIntVolatile	(	Object	object,
		long	fieldOffset,
		int	newValue
	)

Writes an int value to an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to write to.
	fieldOffset	The offset of the field to write to.
	newValue	The value to write.

int org.apache.harmony.kernel.vm.Objects.getIntVolatile	(	Object	object,
		long	fieldOffset
	)

Reads an int value from an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to read from.
	fieldOffset	The offset of the field to read from.

Returns:

The value that was read.

void org.apache.harmony.kernel.vm.Objects.putLongVolatile	(	Object	object,
		long	fieldOffset,
		long	newValue
	)

Writes a long value to an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to write to.
	fieldOffset	The offset of the field to write to.
	newValue	The value to write.

long org.apache.harmony.kernel.vm.Objects.getLongVolatile	(	Object	object,
		long	fieldOffset
	)

Reads a long value from an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to read from.
	fieldOffset	The offset of the field to read from.

Returns:

The value that was read.

void org.apache.harmony.kernel.vm.Objects.putObjectVolatile	(	Object	object,
		long	fieldOffset,
		Object	newValue
	)

Writes an Object reference value to an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to write to.
	fieldOffset	The offset of the field to write to.
	newValue	The value to write.

Object org.apache.harmony.kernel.vm.Objects.getObjectVolatile	(	Object	object,
		long	fieldOffset
	)

Writes an int value to an Object's field as though it were declared volatile.

Parameters:

	object	The instance containing the field to write to.
	fieldOffset	The offset of the field to write to.
	newValue	The value to write.

void org.apache.harmony.kernel.vm.Objects.putLong	(	Object	object,
		long	fieldOffset,
		long	newValue
	)

Writes a long value to an Object's field.

Parameters:

	object	The instance containing the field to write to.
	fieldOffset	The offset of the field to write to.
	newValue	The value to write.

long org.apache.harmony.kernel.vm.Objects.getLong	(	Object	object,
		long	fieldOffset
	)

Reads a long value from an Object's field.

Parameters:

	object	The instance containing the field to read from.
	fieldOffset	The offset of the field to read from.

Returns:

The value that was read.

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The documentation for this class was generated from the following file:

• org/apache/harmony/kernel/vm/Objects.java

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