org.teasoft.bee.osql.transaction

枚举 TransactionIsolationLevel

java.lang.Object

java.lang.Enum<TransactionIsolationLevel>

org.teasoft.bee.osql.transaction.TransactionIsolationLevel

所有已实现的接口:

Serializable, Comparable<TransactionIsolationLevel>

public enum TransactionIsolationLevel
extends Enum<TransactionIsolationLevel>

事务隔离级别.Transaction isolation level.

从以下版本开始:

1.0

作者:

Kingstar

枚举常量概要

枚举常量

枚举常量和说明
TRANSACTION_NONE 指示事务不受支持的常量.A constant indicating that transactions are not supported.
TRANSACTION_READ_COMMITTED 指示不可以发生脏读的常量；不可重复读和虚读可以发生 A constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur.
TRANSACTION_READ_UNCOMMITTED 指示可以发生:脏读 (dirty read)、不可重复读和虚读 (phantom read) 的常量 A constant indicating that dirty reads, non-repeatable reads and phantom reads can occur.
TRANSACTION_REPEATABLE_READ 指示不可以发生脏读和不可重复读的常量；虚读可以发生 A constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur.
TRANSACTION_SERIALIZABLE 指示不可以发生脏读、不可重复读和虚读的常量 A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented.

方法概要

限定符和类型	方法和说明
int	getLevel() 获取隔离级别.get the value of TransactionIsolationLevel.
static TransactionIsolationLevel	valueOf(String name) 返回带有指定名称的该类型的枚举常量。
static TransactionIsolationLevel[]	values() 按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。

从类继承的方法 java.lang.Enum

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

从类继承的方法 java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

枚举常量详细资料

TRANSACTION_NONE

public static final TransactionIsolationLevel TRANSACTION_NONE

指示事务不受支持的常量.A constant indicating that transactions are not supported.

TRANSACTION_READ_UNCOMMITTED

public static final TransactionIsolationLevel TRANSACTION_READ_UNCOMMITTED

指示可以发生:脏读 (dirty read)、不可重复读和虚读 (phantom read) 的常量
A constant indicating that dirty reads, non-repeatable reads and phantom reads can occur. This level allows a row changed by one transaction to be read by another transaction before any changes in that row have been committed (a "dirty read"). If any of the changes are rolled back, the second transaction will have retrieved an invalid row.

TRANSACTION_READ_COMMITTED

public static final TransactionIsolationLevel TRANSACTION_READ_COMMITTED

指示不可以发生脏读的常量；不可重复读和虚读可以发生
A constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur. This level only prohibits a transaction from reading a row with uncommitted changes in it.

TRANSACTION_REPEATABLE_READ

public static final TransactionIsolationLevel TRANSACTION_REPEATABLE_READ

指示不可以发生脏读和不可重复读的常量；虚读可以发生
A constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur. This level prohibits a transaction from reading a row with uncommitted changes in it, and it also prohibits the situation where one transaction reads a row, a second transaction alters the row, and the first transaction rereads the row, getting different values the second time (a "non-repeatable read").

TRANSACTION_SERIALIZABLE

public static final TransactionIsolationLevel TRANSACTION_SERIALIZABLE

指示不可以发生脏读、不可重复读和虚读的常量
A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented. This level includes the prohibitions in TRANSACTION_REPEATABLE_READ and further prohibits the situation where one transaction reads all rows that satisfy a WHERE condition, a second transaction inserts a row that satisfies that WHERE condition, and the first transaction rereads for the same condition, retrieving the additional "phantom" row in the second read.

方法详细资料

values

public static TransactionIsolationLevel[] values()

按照声明该枚举类型的常量的顺序, 返回 包含这些常量的数组。该方法可用于迭代 常量, 如下所示:

for (TransactionIsolationLevel c : TransactionIsolationLevel.values())
    System.out.println(c);

返回:

按照声明该枚举类型的常量的顺序返回的包含这些常量的数组

valueOf

public static TransactionIsolationLevel valueOf(String name)

返回带有指定名称的该类型的枚举常量。 字符串必须与用于声明该类型的枚举常量的 标识符完全匹配。(不允许有多余 的空格字符。)

参数:

name - 要返回的枚举常量的名称。

返回:

返回带有指定名称的枚举常量

抛出:

IllegalArgumentException - 如果该枚举类型没有带有指定名称的常量

NullPointerException - 如果参数为空值

getLevel

public int getLevel()

获取隔离级别.get the value of TransactionIsolationLevel.

返回:

隔离级别的值.value of TransactionIsolationLevel.