org.github.jamm

Interface MemoryMeterStrategy

All Known Implementing Classes:

InstrumentationAndSpecStrategy, MemoryLayoutBasedStrategy, UnsafeStrategy

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface MemoryMeterStrategy

Represents a strategy to measure the shallow memory used by a Java object.

Field Summary

Fields

Modifier and Type	Field and Description
static MemoryLayoutSpecification	MEMORY_LAYOUT The memory layout detected by JAMM.

Method Summary

Modifier and Type	Method and Description
default long	computeArraySize(int length, int elementSize) Computes an array size from its length and element size (optional operation).
long	measure(Object object) Measures the shallow memory used by the specified object.
default long	measureArray(boolean[] array) Measures the shallow memory used by the specified boolean array.
default long	measureArray(byte[] array) Measures the shallow memory used by the specified byte array.
default long	measureArray(char[] array) Measures the shallow memory used by the specified char array.
default long	measureArray(double[] array) Measures the shallow memory used by the specified double array.
default long	measureArray(float[] array) Measures the shallow memory used by the specified float array.
default long	measureArray(int[] array) Measures the shallow memory used by the specified int array.
default long	measureArray(long[] array) Measures the shallow memory used by the specified long array.
default long	measureArray(Object[] array) Measures the shallow memory used by the specified array.
default long	measureArray(Object array, Class<?> type) Measures the shallow memory used by the specified array.
default long	measureArray(short[] array) Measures the shallow memory used by the specified short array.
default boolean	supportComputeArraySize() Checks if this instance supports the computeArraySize operation.

Field Detail

MEMORY_LAYOUT

static final MemoryLayoutSpecification MEMORY_LAYOUT

The memory layout detected by JAMM.

Method Detail

measure

long measure(Object object)

Measures the shallow memory used by the specified object.

Parameters:

object - the object to measure

Returns:

the shallow memory usage of the specified object

measureArray

default long measureArray(Object array,
                          Class<?> type)

Measures the shallow memory used by the specified array.

Parameters:

array - the array to measure

type - the array type

Returns:

the shallow memory usage of the specified array

measureArray

default long measureArray(Object[] array)

Measures the shallow memory used by the specified array.

Parameters:

array - the array to measure

Returns:

the shallow memory used by the specified array.

measureArray

default long measureArray(byte[] array)

Measures the shallow memory used by the specified byte array.

Parameters:

array - the array to measure

Returns:

the shallow memory used by the specified byte array.

measureArray

default long measureArray(boolean[] array)

Measures the shallow memory used by the specified boolean array.

Parameters:

array - the boolean array to measure

Returns:

the shallow memory used by the specified boolean array.

measureArray

default long measureArray(short[] array)

Measures the shallow memory used by the specified short array.

Parameters:

array - the short array to measure

Returns:

the shallow memory used by the specified short array.

measureArray

default long measureArray(char[] array)

Measures the shallow memory used by the specified char array.

Parameters:

array - the char array to measure

Returns:

the shallow memory used by the specified char array.

measureArray

default long measureArray(int[] array)

Measures the shallow memory used by the specified int array.

Parameters:

array - the int array to measure

Returns:

the shallow memory used by the specified int array.

measureArray

default long measureArray(float[] array)

Measures the shallow memory used by the specified float array.

Parameters:

array - the float array to measure

Returns:

the shallow memory used by the specified float array.

measureArray

default long measureArray(long[] array)

Measures the shallow memory used by the specified long array.

Parameters:

array - the long array to measure

Returns:

the shallow memory used by the specified long array.

measureArray

default long measureArray(double[] array)

Measures the shallow memory used by the specified double array.

Parameters:

array - the long array to measure

Returns:

the shallow memory used by the specified double array.

supportComputeArraySize

default boolean supportComputeArraySize()

Checks if this instance supports the computeArraySize operation.

Returns:

true if this instance support the computeArraySize operation, false otherwise.

computeArraySize

default long computeArraySize(int length,
                              int elementSize)

Computes an array size from its length and element size (optional operation).

supportComputeArraySize should be used before calling this method to check if this operation is supported.

Parameters:

length - the array length

elementSize - the size of the elements

Returns:

the array size

Throws:

UnsupportedOperationException - if the operation is not supported