Package org.hibernate

Class LockMode

java.lang.Object
org.hibernate.LockMode
All Implemented Interfaces:
Serializable
public final class LockMode extends Object implements Serializable
Instances represent a lock mode for a row of a relational database table. It is not intended that users spend much time worrying about locking since Hibernate usually obtains exactly the right lock level automatically. Some "advanced" users may wish to explicitly specify lock levels.
See Also:

  • Field Details

    • NONE

      public static final LockMode NONE
      No lock required. If an object is requested with this lock mode, a READ lock will be obtained if it is necessary to actually read the state from the database, rather than pull it from a cache.

      This is the "default" lock mode.

    • READ

      public static final LockMode READ
      A shared lock. Objects in this lock mode were read from the database in the current transaction, rather than being pulled from a cache.

    • UPGRADE

      public static final LockMode UPGRADE
      Deprecated.
      instead use PESSIMISTIC_WRITE
      An upgrade lock. Objects loaded in this lock mode are materialized using an SQL select ... for update.

    • UPGRADE_NOWAIT

      public static final LockMode UPGRADE_NOWAIT
      Attempt to obtain an upgrade lock, using an Oracle-style select for update nowait. The semantics of this lock mode, once obtained, are the same as UPGRADE.

    • WRITE

      public static final LockMode WRITE
      A WRITE lock is obtained when an object is updated or inserted. This lock mode is for internal use only and is not a valid mode for load() or lock() (both of which throw exceptions if WRITE is specified).

    • FORCE

      public static final LockMode FORCE
      Deprecated.
      instead use PESSIMISTIC_FORCE_INCREMENT
      Similiar to UPGRADE except that, for versioned entities, it results in a forced version increment.

    • OPTIMISTIC

      public static final LockMode OPTIMISTIC
      Optimisticly assume that transaction will not experience contention for entities. The entity version will be verified near the transaction end.

    • OPTIMISTIC_FORCE_INCREMENT

      public static final LockMode OPTIMISTIC_FORCE_INCREMENT
      Optimisticly assume that transaction will not experience contention for entities. The entity version will be verified and incremented near the transaction end.

    • PESSIMISTIC_READ

      public static final LockMode PESSIMISTIC_READ
      Implemented as PESSIMISTIC_WRITE. TODO: introduce separate support for PESSIMISTIC_READ

    • PESSIMISTIC_WRITE

      public static final LockMode PESSIMISTIC_WRITE
      Transaction will obtain a database lock immediately. TODO: add PESSIMISTIC_WRITE_NOWAIT

    • PESSIMISTIC_FORCE_INCREMENT

      public static final LockMode PESSIMISTIC_FORCE_INCREMENT
      Transaction will immediately increment the entity version.

  • Method Details

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • greaterThan

      public boolean greaterThan(LockMode mode)
      Check if this lock mode is more restrictive than the given lock mode.
      Parameters:
      mode - LockMode to check
      Returns:
      true if this lock mode is more restrictive than given lock mode

    • lessThan

      public boolean lessThan(LockMode mode)
      Check if this lock mode is less restrictive than the given lock mode.
      Parameters:
      mode - LockMode to check
      Returns:
      true if this lock mode is less restrictive than given lock mode

    • parse

      public static LockMode parse(String name)