Package com.google.common.cache

Class CacheBuilderSpec

java.lang.Object

com.google.common.cache.CacheBuilderSpec

public final class CacheBuilderSpec
extends java.lang.Object

A specification of a CacheBuilder configuration.

CacheBuilderSpec supports parsing configuration off of a string, which makes it especially useful for command-line configuration of a CacheBuilder.

The string syntax is a series of comma-separated keys or key-value pairs, each corresponding to a CacheBuilder method.

• concurrencyLevel=[integer]: sets CacheBuilder.concurrencyLevel.
• initialCapacity=[integer]: sets CacheBuilder.initialCapacity.
• maximumSize=[long]: sets CacheBuilder.maximumSize.
• maximumWeight=[long]: sets CacheBuilder.maximumWeight.
• expireAfterAccess=[duration]: sets CacheBuilder.expireAfterAccess(java.time.Duration).
• expireAfterWrite=[duration]: sets CacheBuilder.expireAfterWrite(java.time.Duration).
• refreshAfterWrite=[duration]: sets CacheBuilder.refreshAfterWrite(java.time.Duration).
• weakKeys: sets CacheBuilder.weakKeys().
• softValues: sets CacheBuilder.softValues().
• weakValues: sets CacheBuilder.weakValues().
• recordStats: sets CacheBuilder.recordStats().

The set of supported keys will grow as CacheBuilder evolves, but existing keys will never be removed.

Durations are represented by an integer, followed by one of "d", "h", "m", or "s", representing days, hours, minutes, or seconds respectively. (There is currently no syntax to request expiration in milliseconds, microseconds, or nanoseconds.)

Whitespace before and after commas and equal signs is ignored. Keys may not be repeated; it is also illegal to use the following pairs of keys in a single value:

• maximumSize and maximumWeight
• softValues and weakValues

CacheBuilderSpec does not support configuring CacheBuilder methods with non-value parameters. These must be configured in code.

A new CacheBuilder can be instantiated from a CacheBuilderSpec using CacheBuilder.from(CacheBuilderSpec) or CacheBuilder.from(String).

Since:

12.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	CacheBuilderSpec.AccessDurationParser	Parse expireAfterAccess
(package private) static class	CacheBuilderSpec.ConcurrencyLevelParser	Parse concurrencyLevel
(package private) static class	CacheBuilderSpec.DurationParser	Base class for parsing times with durations
(package private) static class	CacheBuilderSpec.InitialCapacityParser	Parse initialCapacity
(package private) static class	CacheBuilderSpec.IntegerParser	Base class for parsing integers.
(package private) static class	CacheBuilderSpec.KeyStrengthParser	Parse weakKeys
(package private) static class	CacheBuilderSpec.LongParser	Base class for parsing integers.
(package private) static class	CacheBuilderSpec.MaximumSizeParser	Parse maximumSize
(package private) static class	CacheBuilderSpec.MaximumWeightParser	Parse maximumWeight
(package private) static class	CacheBuilderSpec.RecordStatsParser	Parse recordStats
(package private) static class	CacheBuilderSpec.RefreshDurationParser	Parse refreshAfterWrite
private static interface	CacheBuilderSpec.ValueParser	Parses a single value.
(package private) static class	CacheBuilderSpec.ValueStrengthParser	Parse weakValues and softValues
(package private) static class	CacheBuilderSpec.WriteDurationParser	Parse expireAfterWrite

Field Summary

Fields

Modifier and Type	Field	Description
(package private) long	accessExpirationDuration
(package private) java.util.concurrent.TimeUnit	accessExpirationTimeUnit
(package private) java.lang.Integer	concurrencyLevel
(package private) java.lang.Integer	initialCapacity
private static Splitter	KEY_VALUE_SPLITTER	Splits the key from the value.
private static Splitter	KEYS_SPLITTER	Splits each key-value pair.
(package private) LocalCache.Strength	keyStrength
(package private) java.lang.Long	maximumSize
(package private) java.lang.Long	maximumWeight
(package private) java.lang.Boolean	recordStats
(package private) long	refreshDuration
(package private) java.util.concurrent.TimeUnit	refreshTimeUnit
private java.lang.String	specification	Specification; used for toParseableString().
private static ImmutableMap<java.lang.String,CacheBuilderSpec.ValueParser>	VALUE_PARSERS	Map of names to ValueParser.
(package private) LocalCache.Strength	valueStrength
(package private) long	writeExpirationDuration
(package private) java.util.concurrent.TimeUnit	writeExpirationTimeUnit

Constructor Summary

Constructors

Modifier	Constructor	Description
private	CacheBuilderSpec(java.lang.String specification)

Method Summary

Modifier and Type	Method	Description
static CacheBuilderSpec	disableCaching()	Returns a CacheBuilderSpec that will prevent caching.
private static java.lang.Long	durationInNanos(long duration, java.util.concurrent.TimeUnit unit)	Converts an expiration duration/unit pair into a single Long for hashing and equality.
boolean	equals(java.lang.Object obj)
private static java.lang.String	format(java.lang.String format, java.lang.Object... args)
int	hashCode()
static CacheBuilderSpec	parse(java.lang.String cacheBuilderSpecification)	Creates a CacheBuilderSpec from a string.
(package private) CacheBuilder<java.lang.Object,java.lang.Object>	toCacheBuilder()	Returns a CacheBuilder configured according to this instance's specification.
java.lang.String	toParsableString()	Returns a string that can be used to parse an equivalent CacheBuilderSpec.
java.lang.String	toString()	Returns a string representation for this CacheBuilderSpec instance.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

KEYS_SPLITTER

private static final Splitter KEYS_SPLITTER

Splits each key-value pair.

KEY_VALUE_SPLITTER

private static final Splitter KEY_VALUE_SPLITTER

Splits the key from the value.

VALUE_PARSERS

private static final ImmutableMap<java.lang.String,CacheBuilderSpec.ValueParser> VALUE_PARSERS

Map of names to ValueParser.

initialCapacity

java.lang.Integer initialCapacity

maximumSize

java.lang.Long maximumSize

maximumWeight

java.lang.Long maximumWeight

concurrencyLevel

java.lang.Integer concurrencyLevel

keyStrength

LocalCache.Strength keyStrength

valueStrength

LocalCache.Strength valueStrength

recordStats

java.lang.Boolean recordStats

writeExpirationDuration

long writeExpirationDuration

writeExpirationTimeUnit

java.util.concurrent.TimeUnit writeExpirationTimeUnit

accessExpirationDuration

long accessExpirationDuration

accessExpirationTimeUnit

java.util.concurrent.TimeUnit accessExpirationTimeUnit

refreshDuration

long refreshDuration

refreshTimeUnit

java.util.concurrent.TimeUnit refreshTimeUnit

specification

private final java.lang.String specification

Specification; used for toParseableString().

Constructor Detail

CacheBuilderSpec

private CacheBuilderSpec(java.lang.String specification)

Method Detail

parse

public static CacheBuilderSpec parse(java.lang.String cacheBuilderSpecification)

Creates a CacheBuilderSpec from a string.

Parameters:

cacheBuilderSpecification - the string form

disableCaching

public static CacheBuilderSpec disableCaching()

Returns a CacheBuilderSpec that will prevent caching.

toCacheBuilder

CacheBuilder<java.lang.Object,java.lang.Object> toCacheBuilder()

Returns a CacheBuilder configured according to this instance's specification.

toParsableString

public java.lang.String toParsableString()

Returns a string that can be used to parse an equivalent CacheBuilderSpec. The order and form of this representation is not guaranteed, except that reparsing its output will produce a CacheBuilderSpec equal to this instance.

toString

public java.lang.String toString()

Returns a string representation for this CacheBuilderSpec instance. The form of this representation is not guaranteed.

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

durationInNanos

private static java.lang.Long durationInNanos(long duration,
                                              java.util.concurrent.TimeUnit unit)

Converts an expiration duration/unit pair into a single Long for hashing and equality. Uses nanos to match CacheBuilder implementation.

format

private static java.lang.String format(java.lang.String format,
                                       java.lang.Object... args)