DatastoreTemplate (Spring Cloud GCP Datastore Module 1.1.0.RELEASE API)

java.lang.Object
- org.springframework.cloud.gcp.data.datastore.core.DatastoreTemplate

All Implemented Interfaces:

DatastoreOperations
```
public class DatastoreTemplate
extends Object
implements DatastoreOperations
```
An implementation of DatastoreOperations.

Since:

1.1

Author:

Chengyuan Zhao

Constructor Summary

Constructors
Constructor and Description
`DatastoreTemplate(com.google.cloud.datastore.DatastoreReaderWriter datastore, DatastoreEntityConverter datastoreEntityConverter, DatastoreMappingContext datastoreMappingContext, ObjectToKeyFactory objectToKeyFactory)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static void`	`applyQueryOptions(com.google.cloud.datastore.StructuredQuery.Builder builder, DatastoreQueryOptions queryOptions, DatastorePersistentEntity<?> persistentEntity)`
`<T> List<T>`	`convertEntitiesForRead(Iterator<? extends com.google.cloud.datastore.BaseEntity> entities, Class<T> entityClass)` Convert Datastore entities to objects of a specified type.
`long`	`count(Class<?> entityClass)` Count all occurrences of entities of the given domain type.
`com.google.cloud.datastore.Key`	`createKey(String kind, Object id)` Create a `Key` from kind name and id.
`<T> void`	`delete(T entity)` Delete an entity from Cloud Datastore.
`long`	`deleteAll(Class<?> entityClass)` Delete all entities of a given domain type.
`<T> void`	`deleteAll(Iterable<T> entities)` Deletes multiple entities from Cloud Datastore.
`<T> void`	`deleteAllById(Iterable<?> ids, Class<T> entityClass)` Delete multiple IDs from Cloud Datastore.
`<T> void`	`deleteById(Object id, Class<T> entityClass)` Delete an entity from Cloud Datastore.
`<T> boolean`	`existsById(Object id, Class<T> entityClass)` Check if the given ID belongs to an entity in Cloud Datastore.
`<T> Collection<T>`	`findAll(Class<T> entityClass)` Get all the entities of the given domain type.
`<T> Collection<T>`	`findAll(Class<T> entityClass, DatastoreQueryOptions queryOptions)` Get all the entities of the given domain type applying limit, offset and sort.
`<T> Collection<T>`	`findAllById(Iterable<?> ids, Class<T> entityClass)` Find all the entities of the given IDs.
`<T> T`	`findById(Object id, Class<T> entityClass)` Get an entity based on a id.
`<T> Map<String,T>`	`findByIdAsMap(com.google.cloud.datastore.Key key, Class<T> valueType)` Get a Datastore entity based on a id and convert it to a map.
`DatastoreEntityConverter`	`getDatastoreEntityConverter()` Get the `DatastoreEntityConverter` used by this template.
`static com.google.cloud.datastore.PathElement`	`keyToPathElement(com.google.cloud.datastore.Key key)`
`<A> A`	`performTransaction(Function<DatastoreOperations,A> operations)` Performs multiple read and write operations in a single transaction.
`<T> Iterable<T>`	`query(com.google.cloud.datastore.Query<? extends com.google.cloud.datastore.BaseEntity> query, Class<T> entityClass)` Finds objects by using a Cloud Datastore query.
`<A,T> List<T>`	`query(com.google.cloud.datastore.Query<A> query, Function<A,T> entityFunc)` Runs given query and applies given function to each entity in the result.
`Iterable<com.google.cloud.datastore.Key>`	`queryKeys(com.google.cloud.datastore.Query<com.google.cloud.datastore.Key> query)` Finds Cloud Datastore Keys by using a Cloud Datastore query.
`<T> Iterable<?>`	`queryKeysOrEntities(com.google.cloud.datastore.Query query, Class<T> entityClass)` Finds objects by using a Cloud Datastore query.
`<T> T`	`save(T instance, com.google.cloud.datastore.Key... ancestors)` Saves an instance of an object to Cloud Datastore.
`<T> Iterable<T>`	`saveAll(Iterable<T> entities, com.google.cloud.datastore.Key... ancestors)` Saves multiple instances of objects to Cloud Datastore.
`<V> void`	`writeMap(com.google.cloud.datastore.Key datastoreKey, Map<String,V> map)` Save a map as a Datastore entity, using map keys as field names.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - DatastoreTemplate
```
public DatastoreTemplate(com.google.cloud.datastore.DatastoreReaderWriter datastore,
                         DatastoreEntityConverter datastoreEntityConverter,
                         DatastoreMappingContext datastoreMappingContext,
                         ObjectToKeyFactory objectToKeyFactory)
```
- Method Detail
  - getDatastoreEntityConverter
```
public DatastoreEntityConverter getDatastoreEntityConverter()
```
    Get the DatastoreEntityConverter used by this template.
    
    Returns:
    
    the converter.
  - findById
```
public <T> T findById(Object id,
                      Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Get an entity based on a id.
    
    Specified by:
    
    findById in interface DatastoreOperations
    
    Type Parameters:
    
    T - the class type of the entity.
    
    Parameters:
    
    id - the id of the entity. If this is actually a Key then it will be used. Otherwise it will be attempted to be converted to an integer or string value and it will be assumed to be a root key value with the Kind determined by the entityClass. param.
    
    entityClass - the type of the entity to get.
    
    Returns:
    
    the entity that was found with that id.
  - save
```
public <T> T save(T instance,
                  com.google.cloud.datastore.Key... ancestors)
```
    Description copied from interface: DatastoreOperations
    
    Saves an instance of an object to Cloud Datastore. Behaves as update or insert. Ancestors can be added only to entries with Key ids.
    
    Specified by:
    
    save in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type of the object to save
    
    Parameters:
    
    instance - the instance to save.
    
    ancestors - ancestors that should be added to the entry
    
    Returns:
    
    the instance that was saved.
  - saveAll
```
public <T> Iterable<T> saveAll(Iterable<T> entities,
                               com.google.cloud.datastore.Key... ancestors)
```
    Description copied from interface: DatastoreOperations
    
    Saves multiple instances of objects to Cloud Datastore. Behaves as update or insert. Ancestors can be added only to entries with Key ids.
    
    Specified by:
    
    saveAll in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type of entities to save
    
    Parameters:
    
    entities - the objects to save.
    
    ancestors - ancestors that should be added to each entry
    
    Returns:
    
    the entities that were saved.
  - deleteById
```
public <T> void deleteById(Object id,
                           Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Delete an entity from Cloud Datastore. Deleting IDs that do not exist in Cloud Datastore will result in no operation.
    
    Specified by:
    
    deleteById in interface DatastoreOperations
    
    Type Parameters:
    
    T - ths entity type
    
    Parameters:
    
    id - the ID of the entity to delete. If this is actually a Key then it will be used. Otherwise it will be attempted to be converted to an integer or string value and it will be assumed to be a root key value with the Kind determined by the entityClass.
    
    entityClass - the type of the
  - deleteAllById
```
public <T> void deleteAllById(Iterable<?> ids,
                              Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Delete multiple IDs from Cloud Datastore. Deleting IDs that do not exist in Cloud Datastore will result in no operation.
    
    Specified by:
    
    deleteAllById in interface DatastoreOperations
    
    Type Parameters:
    
    T - ths entity type
    
    Parameters:
    
    ids - the IDs to delete. If any of these is actually a Key then it will be used. Otherwise it will be attempted to be converted to an integer or string value and it will be assumed to be a root key value with the Kind determined by the entityClass.
    
    entityClass - the type of the
  - delete
```
public <T> void delete(T entity)
```
    Description copied from interface: DatastoreOperations
    
    Delete an entity from Cloud Datastore. Deleting entities that don't exist in Cloud Datastore will result in no operation.
    
    Specified by:
    
    delete in interface DatastoreOperations
    
    Type Parameters:
    
    T - the entity type
    
    Parameters:
    
    entity - the entity to delete.
  - deleteAll
```
public <T> void deleteAll(Iterable<T> entities)
```
    Description copied from interface: DatastoreOperations
    
    Deletes multiple entities from Cloud Datastore. Deleting entities that don't exist in Cloud Datastore will result in no operation.
    
    Specified by:
    
    deleteAll in interface DatastoreOperations
    
    Type Parameters:
    
    T - the entity type.
    
    Parameters:
    
    entities - the entities to delete.
  - deleteAll
```
public long deleteAll(Class<?> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Delete all entities of a given domain type.
    
    Specified by:
    
    deleteAll in interface DatastoreOperations
    
    Parameters:
    
    entityClass - the domain type to delete from Cloud Datastore.
    
    Returns:
    
    the number of entities that were deleted.
  - count
```
public long count(Class<?> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Count all occurrences of entities of the given domain type.
    
    Specified by:
    
    count in interface DatastoreOperations
    
    Parameters:
    
    entityClass - the domain type to count.
    
    Returns:
    
    the number of entities of the given type.
  - findAllById
```
public <T> Collection<T> findAllById(Iterable<?> ids,
                                     Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Find all the entities of the given IDs. If an ID is actually a Key then it will be used. Otherwise it will be attempted to be converted to an integer or string value and it will be assumed to be a root key value with the Kind determined by the entityClass.
    
    Specified by:
    
    findAllById in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type parameter of the domain type.
    
    Parameters:
    
    ids - the IDs to search.
    
    entityClass - the domain type of the objects.
    
    Returns:
    
    the entities that were found.
  - query
```
public <T> Iterable<T> query(com.google.cloud.datastore.Query<? extends com.google.cloud.datastore.BaseEntity> query,
                             Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Finds objects by using a Cloud Datastore query.
    
    Specified by:
    
    query in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type of object to retrieve.
    
    Parameters:
    
    query - the query to execute.
    
    entityClass - the type of object to retrieve.
    
    Returns:
    
    a list of the objects found. If no keys could be found the list will be empty.
  - queryKeysOrEntities
```
public <T> Iterable<?> queryKeysOrEntities(com.google.cloud.datastore.Query query,
                                           Class<T> entityClass)
```
    Finds objects by using a Cloud Datastore query. If the query is a key-query, then keys are returned.
    
    Type Parameters:
    
    T - the type of object to retrieve.
    
    Parameters:
    
    query - the query to execute.
    
    entityClass - the type of object to retrieve.
    
    Returns:
    
    a list of the objects found. If no keys could be found the list will be empty.
  - query
```
public <A,T> List<T> query(com.google.cloud.datastore.Query<A> query,
                           Function<A,T> entityFunc)
```
    Description copied from interface: DatastoreOperations
    
    Runs given query and applies given function to each entity in the result.
    
    Specified by:
    
    query in interface DatastoreOperations
    
    Type Parameters:
    
    A - the row type of the query. This type can be either Key or a Cloud Datastore entity.
    
    T - the type to map each entity or key to.
    
    Parameters:
    
    query - the query to run.
    
    entityFunc - the function to apply to each found entity or key.
    
    Returns:
    
    the mapped entities or keys.
  - queryKeys
```
public Iterable<com.google.cloud.datastore.Key> queryKeys(com.google.cloud.datastore.Query<com.google.cloud.datastore.Key> query)
```
    Description copied from interface: DatastoreOperations
    
    Finds Cloud Datastore Keys by using a Cloud Datastore query.
    
    Specified by:
    
    queryKeys in interface DatastoreOperations
    
    Parameters:
    
    query - the query to execute that retrieves only Keys.
    
    Returns:
    
    the list of keys found.
  - findAll
```
public <T> Collection<T> findAll(Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Get all the entities of the given domain type.
    
    Specified by:
    
    findAll in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type param of the domain type.
    
    Parameters:
    
    entityClass - the domain type to get.
    
    Returns:
    
    the entities that were found.
  - findAll
```
public <T> Collection<T> findAll(Class<T> entityClass,
                                 DatastoreQueryOptions queryOptions)
```
    Description copied from interface: DatastoreOperations
    
    Get all the entities of the given domain type applying limit, offset and sort.
    
    Specified by:
    
    findAll in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type param of the domain type.
    
    Parameters:
    
    entityClass - the domain type to get.
    
    queryOptions - query options
    
    Returns:
    
    the entities that were found.
  - applyQueryOptions
```
public static void applyQueryOptions(com.google.cloud.datastore.StructuredQuery.Builder builder,
                                     DatastoreQueryOptions queryOptions,
                                     DatastorePersistentEntity<?> persistentEntity)
```
  - existsById
```
public <T> boolean existsById(Object id,
                              Class<T> entityClass)
```
    Description copied from interface: DatastoreOperations
    
    Check if the given ID belongs to an entity in Cloud Datastore. If this is actually a Key then it will be used. Otherwise it will be attempted to be converted to an integer or string value and it will be assumed to be a root key value with the Kind determined by the entityClass.
    
    Specified by:
    
    existsById in interface DatastoreOperations
    
    Type Parameters:
    
    T - the type param of the domain type.
    
    Parameters:
    
    id - the ID to search for.
    
    entityClass - the domain type of the entities to search for.
    
    Returns:
    
    true if the given ID refers to an existing entity. False otherwise.
  - performTransaction
```
public <A> A performTransaction(Function<DatastoreOperations,A> operations)
```
    Description copied from interface: DatastoreOperations
    
    Performs multiple read and write operations in a single transaction.
    
    Specified by:
    
    performTransaction in interface DatastoreOperations
    
    Type Parameters:
    
    A - the final return type of the operations.
    
    Parameters:
    
    operations - the function that uses DatastoreOperations to perform operations in a transaction.
    
    Returns:
    
    the final result of the transaction.
  - findByIdAsMap
```
public <T> Map<String,T> findByIdAsMap(com.google.cloud.datastore.Key key,
                                       Class<T> valueType)
```
    Description copied from interface: DatastoreOperations
    
    Get a Datastore entity based on a id and convert it to a map.
    
    Specified by:
    
    findByIdAsMap in interface DatastoreOperations
    
    Type Parameters:
    
    T - the value type of the map
    
    Parameters:
    
    key - the key of the entity
    
    valueType - type values should be converted to
    
    Returns:
    
    if an entity for a given key exists, returns the map representation of it, null otherwise
  - writeMap
```
public <V> void writeMap(com.google.cloud.datastore.Key datastoreKey,
                         Map<String,V> map)
```
    Description copied from interface: DatastoreOperations
    
    Save a map as a Datastore entity, using map keys as field names.
    
    Specified by:
    
    writeMap in interface DatastoreOperations
    
    Type Parameters:
    
    V - the value type of the map to write
    
    Parameters:
    
    datastoreKey - the key for the entity
    
    map - a map
  - createKey
```
public com.google.cloud.datastore.Key createKey(String kind,
                                                Object id)
```
    Description copied from interface: DatastoreOperations
    
    Create a Key from kind name and id.
    
    Specified by:
    
    createKey in interface DatastoreOperations
    
    Parameters:
    
    kind - the Cloud Datastore kind name
    
    id - object to be used as id; if it is a Long, the value is used, otherwise it is converted to String
    
    Returns:
    
    created key
  - keyToPathElement
```
public static com.google.cloud.datastore.PathElement keyToPathElement(com.google.cloud.datastore.Key key)
```
  - convertEntitiesForRead
```
public <T> List<T> convertEntitiesForRead(Iterator<? extends com.google.cloud.datastore.BaseEntity> entities,
                                          Class<T> entityClass)
```
    Convert Datastore entities to objects of a specified type.
    
    Type Parameters:
    
    T - the type the entities should be converted to.
    
    Parameters:
    
    entities - the Datastore entities
    
    entityClass - the type the entities should be converted to.
    
    Returns:
    
    a list of converted entities

Class DatastoreTemplate

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

DatastoreTemplate

Method Detail

getDatastoreEntityConverter

findById

save

saveAll

deleteById

deleteAllById

delete

deleteAll

deleteAll

count

findAllById

query

queryKeysOrEntities

query

queryKeys

findAll

findAll

applyQueryOptions

existsById

performTransaction

findByIdAsMap

writeMap

createKey

keyToPathElement

convertEntitiesForRead