Enum Class LockUpgradeRule

java.lang.Object

java.lang.Enum<LockUpgradeRule>

org.cojen.tupl.LockUpgradeRule

All Implemented Interfaces:

Serializable, Comparable<LockUpgradeRule>, Constable

public enum LockUpgradeRule
extends Enum<LockUpgradeRule>

Defines transaction lock upgrade behavior when using the REPEATABLE_READ lock mode.

Rules ordered from strongest to weakest:

• STRICT (default)
• LENIENT
• UNCHECKED

See Also:

• DatabaseConfig.lockUpgradeRule(org.cojen.tupl.LockUpgradeRule)

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Enum

Enum.EnumDesc<E extends Enum<E>>

Enum Constant Summary

Enum Constants

Enum Constant	Description
LENIENT	Rule which allows an upgrade to succeed, but only when the acting transaction is the sole shared lock owner.
STRICT	Rule which rejects any shared lock upgrade as illegal.
UNCHECKED	Rule which always attempts an upgrade, potentially causing a deadlock if multiple transactions are making the same attempt.

Method Summary

Modifier and Type	Method	Description
static LockUpgradeRule	valueOf(String name)	Returns the enum constant of this class with the specified name.
static LockUpgradeRule[]	values()	Returns an array containing the constants of this enum class, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, describeConstable, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Details

STRICT

public static final LockUpgradeRule STRICT

Rule which rejects any shared lock upgrade as illegal. The lock must first be acquired as upgradable.

LENIENT

public static final LockUpgradeRule LENIENT

Rule which allows an upgrade to succeed, but only when the acting transaction is the sole shared lock owner. If other transactions are also holding the lock, the upgrade attempt is illegal.

UNCHECKED

public static final LockUpgradeRule UNCHECKED

Rule which always attempts an upgrade, potentially causing a deadlock if multiple transactions are making the same attempt.

Method Details

values

public static LockUpgradeRule[] values()

Returns an array containing the constants of this enum class, in the order they are declared.

Returns:

an array containing the constants of this enum class, in the order they are declared

valueOf

public static LockUpgradeRule valueOf(String name)

Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (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 class has no constant with the specified name

NullPointerException - if the argument is null