MemoryUnit (OpenHFT/Java-Lang/lang 6.6.7 API)

java.lang.Object
- java.lang.Enum<MemoryUnit>
- - net.openhft.lang.MemoryUnit

All Implemented Interfaces:

Serializable, Comparable<MemoryUnit>
```
public enum MemoryUnit
extends Enum<MemoryUnit>
```
A MemoryUnit represents memory amounts at a given unit of granularity and provides utility methods to convert across units. A MemoryUnit does not maintain memory information, but only helps organize and use memory amounts representations that may be maintained separately across various contexts.
Note than in this class kilo-, mega- and giga- prefixes means 2^10 = 1024 multiplexing, that is more common in low-level programming, CPU and operation system contexts, not 1000 as defined by International System of Units (SI).
A MemoryUnit is mainly used to inform memory amount-based methods how a given memory amount parameter should be interpreted.
API of MemoryUnit is copied from TimeUnit enum.

Enum Constant Summary

Enum Constants
Enum Constant and Description
`BITS` Memory unit representing one bit.
`BYTES` Memory unit representing one byte, i.
`CACHE_LINES` Memory unit representing 64 bytes, i.
`GIGABYTES` Memory unit representing 1024 megabytes.
`KILOBYTES` Memory unit representing 1024 bytes.
`LONGS` Memory unit representing 8 bytes, i.
`MEGABYTES` Memory unit representing 1024 kilobytes.
`PAGES` Memory unit representing 4096 bytes, i.

Method Summary

Methods
Modifier and Type	Method and Description
`long`	`align(long amountToAlign, MemoryUnit unit)` Aligns the given memory amount in the given unit to this unit.
`long`	`alignAndConvert(long sourceAmount, MemoryUnit sourceUnit)` Equivalent to `convert(align(sourceAmount, sourceUnit), sourceUnit)`.
`long`	`convert(long sourceAmount, MemoryUnit sourceUnit)` Converts the given memory amount in the given unit to this unit.
`long`	`toBits(long amount)` Equivalent to `BITS.convert(amount, this)`.
`long`	`toBytes(long amount)` Equivalent to `BYTES.convert(amount, this)`.
`long`	`toCacheLines(long amount)` Equivalent to `CACHE_LINES.convert(amount, this)`.
`long`	`toGigabytes(long amount)` Equivalent to `GIGABYTES.convert(amount, this)`.
`long`	`toKilobytes(long amount)` Equivalent to `KILOBYTES.convert(amount, this)`.
`long`	`toLongs(long amount)` Equivalent to `LONGS.convert(amount, this)`.
`long`	`toMegabytes(long amount)` Equivalent to `MEGABYTES.convert(amount, this)`.
`long`	`toPages(long amount)` Equivalent to `PAGES.convert(amount, this)`.
`static MemoryUnit`	`valueOf(String name)` Returns the enum constant of this type with the specified name.
`static MemoryUnit[]`	`values()` Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait

- Enum Constant Detail
  - BITS
```
public static final MemoryUnit BITS
```
    Memory unit representing one bit.
  - BYTES
```
public static final MemoryUnit BYTES
```
    Memory unit representing one byte, i. e. 8 bits.
  - LONGS
```
public static final MemoryUnit LONGS
```
    Memory unit representing 8 bytes, i. e. 64-bit word, the width of Java's primitive long type.
  - CACHE_LINES
```
public static final MemoryUnit CACHE_LINES
```
    Memory unit representing 64 bytes, i. e. the most common CPU cache line size.
  - KILOBYTES
```
public static final MemoryUnit KILOBYTES
```
    Memory unit representing 1024 bytes.
  - PAGES
```
public static final MemoryUnit PAGES
```
    Memory unit representing 4096 bytes, i. e. the most common native memory page size.
  - MEGABYTES
```
public static final MemoryUnit MEGABYTES
```
    Memory unit representing 1024 kilobytes.
  - GIGABYTES
```
public static final MemoryUnit GIGABYTES
```
    Memory unit representing 1024 megabytes.
- Method Detail
  - values
```
public static MemoryUnit[] values()
```
    Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
```
for (MemoryUnit c : MemoryUnit.values())
    System.out.println(c);
```
    Returns:
    an array containing the constants of this enum type, in the order they are declared
  - valueOf
```
public static MemoryUnit valueOf(String name)
```
    Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
    
    Parameters:
    name - the name of the enum constant to be returned.
    
    Returns:
    the enum constant with the specified name
    
    Throws:
    
    IllegalArgumentException - if this enum type has no constant with the specified name
    
    NullPointerException - if the argument is null
  - convert
```
public long convert(long sourceAmount,
           MemoryUnit sourceUnit)
```
    Converts the given memory amount in the given unit to this unit. Conversions from finer to coarser granularities truncate, so lose precision. For example, converting 7 bits to bytes results in 0. Conversions from coarser to finer granularities with arguments that would numerically overflow saturate to Long.MIN_VALUE if negative or Long.MAX_VALUE if positive.
    For example, to convert 4096 bytes to cache lines, use: MemoryUnit.CACHE_LINES.convert(4096L, MemoryUnit.BYTES)
    
    Parameters:
    sourceAmount - the memory amount in the given sourceUnit
    sourceUnit - the unit of the sourceAmount argument
    
    Returns:
    the converted amount in this unit, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - align
```
public long align(long amountToAlign,
         MemoryUnit unit)
```
    Aligns the given memory amount in the given unit to this unit. For example, aligning 1000 bytes to kilobytes results in 1024. Negative values are aligned towards negative infinity: e. g. aligning -5 longs to cache lines results in -8.
    
    Parameters:
    amountToAlign - the memory amount in the given unit
    unit - the unit of the amountToAlign argument
    
    Returns:
    the aligned amount, still in the given unit
    
    Throws:
    
    IllegalArgumentException - if the given unit is finer than this unit, or if the aligned value overflows long bounds
  - alignAndConvert
```
public long alignAndConvert(long sourceAmount,
                   MemoryUnit sourceUnit)
```
    Equivalent to convert(align(sourceAmount, sourceUnit), sourceUnit).
    
    Parameters:
    sourceAmount - the memory amount in the given sourceUnit
    sourceUnit - the unit of the sourceAmount argument
    
    Returns:
    the saturated converted amount in this unit
    
    Throws:
    
    IllegalArgumentException - if the given sourceUnit is finer than this unit, or if the aligned value overflows long bounds
  - toBits
```
public long toBits(long amount)
```
    Equivalent to BITS.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toBytes
```
public long toBytes(long amount)
```
    Equivalent to BYTES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toLongs
```
public long toLongs(long amount)
```
    Equivalent to LONGS.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toCacheLines
```
public long toCacheLines(long amount)
```
    Equivalent to CACHE_LINES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toKilobytes
```
public long toKilobytes(long amount)
```
    Equivalent to KILOBYTES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toPages
```
public long toPages(long amount)
```
    Equivalent to PAGES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toMegabytes
```
public long toMegabytes(long amount)
```
    Equivalent to MEGABYTES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount, or Long.MIN_VALUE if conversion would negatively overflow, or Long.MAX_VALUE if it would positively overflow.
  - toGigabytes
```
public long toGigabytes(long amount)
```
    Equivalent to GIGABYTES.convert(amount, this).
    
    Parameters:
    amount - the amount
    
    Returns:
    the converted amount

Enum MemoryUnit

Enum Constant Summary

Method Summary

Methods inherited from class java.lang.Enum

Methods inherited from class java.lang.Object

Enum Constant Detail

BITS

BYTES

LONGS

CACHE_LINES

KILOBYTES

PAGES

MEGABYTES

GIGABYTES

Method Detail

values

valueOf

convert

align

alignAndConvert

toBits

toBytes

toLongs

toCacheLines

toKilobytes

toPages

toMegabytes

toGigabytes