org.springframework.transaction.annotation

## Enum Isolation

- java.lang.Object
- - java.lang.Enum<Isolation>
  - - org.springframework.transaction.annotation.Isolation

All Implemented Interfaces:
  Serializable, Comparable<Isolation>

    public enum Isolation
    extends Enum<Isolation>

Enumeration that represents transaction isolation levels for use with the `Transactional` annotation, corresponding to the `TransactionDefinition` interface.

Since:
  1.2
Author:
  Colin Sampaleanu, Juergen Hoeller

### Enum Constant Summary

Enum Constants
Enum Constant and Description
`DEFAULT` Use the default isolation level of the underlying datastore.
`READ_COMMITTED` A constant indicating that dirty reads are prevented; non-repeatable reads and phantom reads can occur.
`READ_UNCOMMITTED` A constant indicating that dirty reads, non-repeatable reads and phantom reads can occur.
`REPEATABLE_READ` A constant indicating that dirty reads and non-repeatable reads are prevented; phantom reads can occur.
`SERIALIZABLE` A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented.

### Method Summary

Methods
`int` `value()`
`static Isolation` `valueOf(String name)` Returns the enum constant of this type with the specified name.
`static Isolation[]` `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

#### DEFAULT

    public static final Isolation DEFAULT

Use the default isolation level of the underlying datastore. All other levels correspond to the JDBC isolation levels.

See Also:
  `Connection`

#### READ_UNCOMMITTED

    public static final Isolation READ_UNCOMMITTED

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.

See Also:
  `Connection.TRANSACTION_READ_UNCOMMITTED`

#### READ_COMMITTED

    public static final Isolation READ_COMMITTED

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.

See Also:
  `Connection.TRANSACTION_READ_COMMITTED`

#### REPEATABLE_READ

    public static final Isolation REPEATABLE_READ

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").

See Also:
  `Connection.TRANSACTION_REPEATABLE_READ`

#### SERIALIZABLE

    public static final Isolation SERIALIZABLE

A constant indicating that dirty reads, non-repeatable reads and phantom reads are prevented. This level includes the prohibitions in `ISOLATION_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.

See Also:
  `Connection.TRANSACTION_SERIALIZABLE`

### Method Detail

#### values

    public static Isolation[] 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 (Isolation c : Isolation.values())
        System.out.println(c);

Returns:
  an array containing the constants of this enum type, in the order they are declared

#### valueOf

    public static Isolation 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

#### value

    public int value()