All Known Subinterfaces:

JpaTransactionManager

All Known Implementing Classes:

DatastoreTransactionManager, JpaTransactionManagerImpl
```
public interface TransactionManager
```
This interface defines the methods to execute database operations with or without a transaction.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`assertInTransaction()`	Throws `IllegalStateException` if the caller is not in a transaction.
`void`	`clearSessionCache()`	Clears the session cache if the underlying database is Datastore, otherwise it is a no-op.
`<T> QueryComposer<T>`	`createQueryComposer(java.lang.Class<T> entity)`	Returns a QueryComposer which can be used to perform queries against the current database.
`void`	`delete(VKey<?> key)`	Deletes the entity by its id.
`void`	`delete(java.lang.Iterable<? extends VKey<?>> keys)`	Deletes the set of entities by their key id.
`void`	`delete(java.lang.Object entity)`	Deletes the given entity from the database.
`void`	`deleteWithoutBackup(VKey<?> key)`	Deletes the entity by its id without writing commit logs if the underlying database is Datastore.
`void`	`deleteWithoutBackup(java.lang.Iterable<? extends VKey<?>> keys)`	Deletes the set of entities by their key id without writing commit logs if the underlying database is Datastore.
`void`	`deleteWithoutBackup(java.lang.Object entity)`	Deletes the given entity from the database without writing commit logs if the underlying database is Datastore.
`<R> R`	`doTransactionless(java.util.function.Supplier<R> work)`	Executes the work in a transactionless context.
`<T> boolean`	`exists(VKey<T> key)`	Returns whether the entity of given key exists.
`boolean`	`exists(java.lang.Object entity)`	Returns whether the given entity with same ID exists.
`org.joda.time.DateTime`	`getTransactionTime()`	Returns the time associated with the start of this particular transaction attempt.
`void`	`insert(java.lang.Object entity)`	Persists a new entity in the database, throws exception if the entity already exists.
`void`	`insertAll(com.google.common.collect.ImmutableCollection<?> entities)`	Persists all new entities in the database, throws exception if any entity already exists.
`void`	`insertAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)`	Persists all new entities in the database without writing any backup if the underlying database is Datastore.
`void`	`insertWithoutBackup(java.lang.Object entity)`	Persists a new entity in the database without writing any backup if the underlying database is Datastore.
`boolean`	`inTransaction()`	Returns `true` if the caller is in a transaction.
`boolean`	`isOfy()`	Returns true if the transaction manager is DatastoreTransactionManager, false otherwise.
`<T> com.google.common.collect.ImmutableList<T>`	`loadAllOf(java.lang.Class<T> clazz)`	Returns a stream of all entities of the given type that exist in the database.
`<T> com.google.common.collect.ImmutableList<T>`	`loadByEntities(java.lang.Iterable<T> entities)`	Loads all given entities from the database.
`<T> com.google.common.collect.ImmutableList<T>`	`loadByEntitiesIfPresent(java.lang.Iterable<T> entities)`	Loads all given entities from the database if possible.
`<T> T`	`loadByEntity(T entity)`	Loads the given entity from the database.
`<T> T`	`loadByKey(VKey<T> key)`	Loads the entity by its key.
`<T> java.util.Optional<T>`	`loadByKeyIfPresent(VKey<T> key)`	Loads the entity by its key, returns empty if the entity doesn't exist.
`<T> com.google.common.collect.ImmutableMap<VKey<? extends T>,T>`	`loadByKeys(java.lang.Iterable<? extends VKey<? extends T>> keys)`	Loads the set of entities by their keys.
`<T> com.google.common.collect.ImmutableMap<VKey<? extends T>,T>`	`loadByKeysIfPresent(java.lang.Iterable<? extends VKey<? extends T>> keys)`	Loads the set of entities by their keys.
`void`	`put(java.lang.Object entity)`	Persists a new entity or update the existing entity in the database.
`void`	`putAll(com.google.common.collect.ImmutableCollection<?> entities)`	Persists all new entities or updates the existing entities in the database.
`void`	`putAll(java.lang.Object... entities)`	Persists all new entities or updates the existing entities in the database.
`void`	`putAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)`	Persists all new entities or update the existing entities in the database without writing commit logs if the underlying database is Datastore.
`void`	`putWithoutBackup(java.lang.Object entity)`	Persists a new entity or update the existing entity in the database without writing commit logs if the underlying database is Datastore.
`void`	`transact(java.lang.Runnable work)`	Executes the work in a transaction.
`<T> T`	`transact(java.util.function.Supplier<T> work)`	Executes the work in a transaction and returns the result.
`void`	`transactNew(java.lang.Runnable work)`	Pauses the current transaction (if any) and executes the work in a new transaction.
`<T> T`	`transactNew(java.util.function.Supplier<T> work)`	Pauses the current transaction (if any), executes the work in a new transaction and returns the result.
`void`	`transactNewReadOnly(java.lang.Runnable work)`	Executes the work in a read-only transaction.
`<R> R`	`transactNewReadOnly(java.util.function.Supplier<R> work)`	Executes the work in a read-only transaction and returns the result.
`void`	`update(java.lang.Object entity)`	Updates an entity in the database, throws exception if the entity does not exist.
`void`	`updateAll(com.google.common.collect.ImmutableCollection<?> entities)`	Updates all entities in the database, throws exception if any entity does not exist.
`void`	`updateAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)`	Updates all entities in the database without writing any backup if the underlying database is Datastore.
`void`	`updateWithoutBackup(java.lang.Object entity)`	Updates an entity in the database without writing commit logs if the underlying database is Datastore.

- Method Detail
  - inTransaction
```
boolean inTransaction()
```
    Returns true if the caller is in a transaction.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - assertInTransaction
```
void assertInTransaction()
```
    Throws IllegalStateException if the caller is not in a transaction.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - transact
```
<T> T transact(java.util.function.Supplier<T> work)
```
    Executes the work in a transaction and returns the result.
  - transact
```
void transact(java.lang.Runnable work)
```
    Executes the work in a transaction.
  - transactNew
```
<T> T transactNew(java.util.function.Supplier<T> work)
```
    Pauses the current transaction (if any), executes the work in a new transaction and returns the result.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - transactNew
```
void transactNew(java.lang.Runnable work)
```
    Pauses the current transaction (if any) and executes the work in a new transaction.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - transactNewReadOnly
```
<R> R transactNewReadOnly(java.util.function.Supplier<R> work)
```
    Executes the work in a read-only transaction and returns the result.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - transactNewReadOnly
```
void transactNewReadOnly(java.lang.Runnable work)
```
    Executes the work in a read-only transaction.
    Note that this function is kept for backward compatibility. We will review the use case later when adding the cloud sql implementation.
  - doTransactionless
```
<R> R doTransactionless(java.util.function.Supplier<R> work)
```
    Executes the work in a transactionless context.
  - getTransactionTime
```
org.joda.time.DateTime getTransactionTime()
```
    Returns the time associated with the start of this particular transaction attempt.
  - insert
```
void insert(java.lang.Object entity)
```
    Persists a new entity in the database, throws exception if the entity already exists.
  - insertAll
```
void insertAll(com.google.common.collect.ImmutableCollection<?> entities)
```
    Persists all new entities in the database, throws exception if any entity already exists.
  - insertWithoutBackup
```
void insertWithoutBackup(java.lang.Object entity)
```
    Persists a new entity in the database without writing any backup if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy() with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - insertAllWithoutBackup
```
void insertAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)
```
    Persists all new entities in the database without writing any backup if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy() with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - put
```
void put(java.lang.Object entity)
```
    Persists a new entity or update the existing entity in the database.
  - putAll
```
void putAll(java.lang.Object... entities)
```
    Persists all new entities or updates the existing entities in the database.
  - putAll
```
void putAll(com.google.common.collect.ImmutableCollection<?> entities)
```
    Persists all new entities or updates the existing entities in the database.
  - putWithoutBackup
```
void putWithoutBackup(java.lang.Object entity)
```
    Persists a new entity or update the existing entity in the database without writing commit logs if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy() with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - putAllWithoutBackup
```
void putAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)
```
    Persists all new entities or update the existing entities in the database without writing commit logs if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy() with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - update
```
void update(java.lang.Object entity)
```
    Updates an entity in the database, throws exception if the entity does not exist.
  - updateAll
```
void updateAll(com.google.common.collect.ImmutableCollection<?> entities)
```
    Updates all entities in the database, throws exception if any entity does not exist.
  - updateWithoutBackup
```
void updateWithoutBackup(java.lang.Object entity)
```
    Updates an entity in the database without writing commit logs if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy calls with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - updateAllWithoutBackup
```
void updateAllWithoutBackup(com.google.common.collect.ImmutableCollection<?> entities)
```
    Updates all entities in the database without writing any backup if the underlying database is Datastore.
    This method is for the sake of keeping a single code path when replacing ofy calls with tm() in the application code. When the method is invoked with Datastore, it won't write the commit log backup; when invoked with Cloud SQL, it behaves the same as the method which doesn't have "WithoutBackup" in its method name because it is not necessary to have the backup mechanism in SQL.
  - exists
```
boolean exists(java.lang.Object entity)
```
    Returns whether the given entity with same ID exists.
  - exists
```
<T> boolean exists(VKey<T> key)
```
    Returns whether the entity of given key exists.
  - loadByKeyIfPresent
```
<T> java.util.Optional<T> loadByKeyIfPresent(VKey<T> key)
```
    Loads the entity by its key, returns empty if the entity doesn't exist.
  - loadByKeysIfPresent
```
<T> com.google.common.collect.ImmutableMap<VKey<? extends T>,T> loadByKeysIfPresent(java.lang.Iterable<? extends VKey<? extends T>> keys)
```
    Loads the set of entities by their keys.
    Nonexistent keys / entities are absent from the resulting map, but no NoSuchElementException will be thrown.
  - loadByEntitiesIfPresent
```
<T> com.google.common.collect.ImmutableList<T> loadByEntitiesIfPresent(java.lang.Iterable<T> entities)
```
    Loads all given entities from the database if possible.
    Nonexistent entities are absent from the resulting list, but no NoSuchElementException will be thrown.
  - loadByKey
```
<T> T loadByKey(VKey<T> key)
```
    Loads the entity by its key.
    
    Throws:
    
    java.util.NoSuchElementException - if this key does not correspond to an existing entity.
  - loadByKeys
```
<T> com.google.common.collect.ImmutableMap<VKey<? extends T>,T> loadByKeys(java.lang.Iterable<? extends VKey<? extends T>> keys)
```
    Loads the set of entities by their keys.
    
    Throws:
    
    java.util.NoSuchElementException - if any of the keys do not correspond to an existing entity.
  - loadByEntity
```
<T> T loadByEntity(T entity)
```
    Loads the given entity from the database.
    
    Throws:
    
    java.util.NoSuchElementException - if the entity does not exist in the database.
  - loadByEntities
```
<T> com.google.common.collect.ImmutableList<T> loadByEntities(java.lang.Iterable<T> entities)
```
    Loads all given entities from the database.
    
    Throws:
    
    java.util.NoSuchElementException - if any of the entities do not exist in the database.
  - loadAllOf
```
<T> com.google.common.collect.ImmutableList<T> loadAllOf(java.lang.Class<T> clazz)
```
    Returns a stream of all entities of the given type that exist in the database.
    The resulting stream is empty if there are no entities of this type. In Datastore mode, if the class is a member of the cross-TLD entity group (i.e. if it has the InCrossTld annotation, then the correct ancestor query will automatically be applied.
  - delete
```
void delete(VKey<?> key)
```
    Deletes the entity by its id.
  - delete
```
void delete(java.lang.Iterable<? extends VKey<?>> keys)
```
    Deletes the set of entities by their key id.
  - delete
```
void delete(java.lang.Object entity)
```
    Deletes the given entity from the database.
  - deleteWithoutBackup
```
void deleteWithoutBackup(VKey<?> key)
```
    Deletes the entity by its id without writing commit logs if the underlying database is Datastore.
  - deleteWithoutBackup
```
void deleteWithoutBackup(java.lang.Iterable<? extends VKey<?>> keys)
```
    Deletes the set of entities by their key id without writing commit logs if the underlying database is Datastore.
  - deleteWithoutBackup
```
void deleteWithoutBackup(java.lang.Object entity)
```
    Deletes the given entity from the database without writing commit logs if the underlying database is Datastore.
  - createQueryComposer
```
<T> QueryComposer<T> createQueryComposer(java.lang.Class<T> entity)
```
    Returns a QueryComposer which can be used to perform queries against the current database.
  - clearSessionCache
```
void clearSessionCache()
```
    Clears the session cache if the underlying database is Datastore, otherwise it is a no-op.
  - isOfy
```
boolean isOfy()
```
    Returns true if the transaction manager is DatastoreTransactionManager, false otherwise.

Interface TransactionManager

Method Summary

Method Detail

inTransaction

assertInTransaction

transact

transact

transactNew

transactNew

transactNewReadOnly

transactNewReadOnly

doTransactionless

getTransactionTime

insert

insertAll

insertWithoutBackup

insertAllWithoutBackup

put

putAll

putAll

putWithoutBackup

putAllWithoutBackup

update

updateAll

updateWithoutBackup

updateAllWithoutBackup

exists

exists

loadByKeyIfPresent

loadByKeysIfPresent

loadByEntitiesIfPresent

loadByKey

loadByKeys

loadByEntity

loadByEntities

loadAllOf

delete

delete

delete

deleteWithoutBackup

deleteWithoutBackup

deleteWithoutBackup

createQueryComposer

clearSessionCache

isOfy