Class DatastoreHelper (2.19.0)

public final class DatastoreHelper

Helper methods for Datastore.

Inheritance

java.lang.Object > DatastoreHelper

Inherited Members

Object.clone()

Object.equals(Object)

Object.finalize()

Object.getClass()

Object.hashCode()

Object.notify()

Object.notifyAll()

Object.toString()

Object.wait()

Object.wait(long)

Object.wait(long,int)

Static Fields

KEY_PROPERTY_NAME

public static final String KEY_PROPERTY_NAME

The property used in the Datastore to get the key of the entity. *

Field Value
Type	Description
`String`

LOCAL_HOST_ENV_VAR

public static final String LOCAL_HOST_ENV_VAR

Name of the environment variable used to set the local host.

Field Value
Type	Description
`String`

PRIVATE_KEY_FILE_ENV_VAR

public static final String PRIVATE_KEY_FILE_ENV_VAR

Name of the environment variable used to set the private key file.

Field Value
Type	Description
`String`

PROJECT_ID_ENV_VAR

public static final String PROJECT_ID_ENV_VAR

Name of the environment variable used to set the project ID.

Field Value
Type	Description
`String`

SCATTER_PROPERTY_NAME

public static final String SCATTER_PROPERTY_NAME

The property used in the Datastore to give us a random distribution. *

Field Value
Type	Description
`String`

SERVICE_ACCOUNT_ENV_VAR

public static final String SERVICE_ACCOUNT_ENV_VAR

Name of the environment variable used to set the service account.

Field Value
Type	Description
`String`

Static Methods

getBoolean(Value value)

public static boolean getBoolean(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`boolean`	the boolean contained in value

getByteString(Value value)

public static ByteString getByteString(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`ByteString`	the blob contained in value

getDatastoreFromEnv()

public static Datastore getDatastoreFromEnv()

getDouble(Value value)

public static double getDouble(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`double`	the double contained in value

getEntity(Value value)

public static Entity getEntity(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`Entity`	the entity contained in value

getKey(Value value)

public static Key getKey(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`Key`	the key contained in value

getKeyComparator()

public static Comparator<Key> getKeyComparator()

Returns
Type	Description
`Comparator<Key>`

getList(Value value)

public static List<Value> getList(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`List<Value>`	the array contained in value as a list.

getLong(Value value)

public static long getLong(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`long`	the long contained in value

getOptionsFromEnv()

public static DatastoreOptions.Builder getOptionsFromEnv()

Constructs a Datastore from environment variables and/or the Compute Engine metadata server.

The project ID is determined from, in order of preference:

DATASTORE_PROJECT_ID environment variable
Compute Engine

Credentials are taken from, in order of preference:

No credentials (if the DATASTORE_EMULATOR_HOST environment variable is set)
Service Account specified by the DATASTORE_SERVICE_ACCOUNT and DATASTORE_PRIVATE_KEY_FILE environment variables
Google Application Default as described here.

Returns
Type	Description
`DatastoreOptions.Builder`

Exceptions
Type	Description
`GeneralSecurityException`
`IOException`

getProjectIdFromComputeEngine()

public static String getProjectIdFromComputeEngine()

Gets the project ID from the Compute Engine metadata server. Returns null if the project ID cannot be determined (because, for instance, the code is not running on Compute Engine).

Returns
Type	Description
`String`

getQuerySplitter()

public static QuerySplitter getQuerySplitter()

Gets a QuerySplitter.

The returned QuerySplitter#getSplits cannot accept a query that contains inequality filters, a sort filter, or a missing kind.

Returns
Type	Description
`QuerySplitter`

getServiceAccountCredential(String serviceAccountId, String privateKeyFile)

public static Credential getServiceAccountCredential(String serviceAccountId, String privateKeyFile)

Constructs credentials for the given account and key.

Parameters
Name	Description
`serviceAccountId`	`String` service account ID (typically an e-mail address).
`privateKeyFile`	`String` the file name from which to get the private key.

Returns
Type	Description
`com.google.api.client.auth.oauth2.Credential`	valid credentials or `null`

Exceptions
Type	Description
`GeneralSecurityException`
`IOException`

getServiceAccountCredential(String serviceAccountId, String privateKeyFile, Collection<String> serviceAccountScopes)

public static Credential getServiceAccountCredential(String serviceAccountId, String privateKeyFile, Collection<String> serviceAccountScopes)

Constructs credentials for the given account and key file.

Parameters
Name	Description
`serviceAccountId`	`String` service account ID (typically an e-mail address).
`privateKeyFile`	`String` the file name from which to get the private key.
`serviceAccountScopes`	`Collection<String>` Collection of OAuth scopes to use with the the service account flow or `null` if not.

Returns
Type	Description
`com.google.api.client.auth.oauth2.Credential`	valid credentials or `null`

Exceptions
Type	Description
`GeneralSecurityException`
`IOException`

getServiceAccountCredential(String serviceAccountId, PrivateKey privateKey, Collection<String> serviceAccountScopes)

public static Credential getServiceAccountCredential(String serviceAccountId, PrivateKey privateKey, Collection<String> serviceAccountScopes)

Constructs credentials for the given account and key.

Parameters
Name	Description
`serviceAccountId`	`String` service account ID (typically an e-mail address).
`privateKey`	`PrivateKey` the private key for the given account.
`serviceAccountScopes`	`Collection<String>` Collection of OAuth scopes to use with the the service account flow or `null` if not.

Returns
Type	Description
`com.google.api.client.auth.oauth2.Credential`	valid credentials or `null`

Exceptions
Type	Description
`GeneralSecurityException`
`IOException`

getString(Value value)

public static String getString(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`String`	the string contained in value

getTimestamp(Value value)

public static long getTimestamp(Value value)

Parameter
Name	Description
`value`	`Value`

Returns
Type	Description
`long`	the timestamp in microseconds contained in value

makeAncestorFilter(Key ancestor)

public static Filter.Builder makeAncestorFilter(Key ancestor)

Makes an ancestor filter.

Parameter
Name	Description
`ancestor`	`Key`

Returns
Type	Description
`Filter.Builder`

makeAndFilter(Filter[] subfilters)

public static Filter.Builder makeAndFilter(Filter[] subfilters)

Make a composite filter from the given sub-filters using AND to combine filters.

Parameter
Name	Description
`subfilters`	`Filter[]`

Returns
Type	Description
`Filter.Builder`

makeAndFilter(Iterable<Filter> subfilters)

public static Filter.Builder makeAndFilter(Iterable<Filter> subfilters)

Make a composite filter from the given sub-filters using AND to combine filters.

Parameter
Name	Description
`subfilters`	`Iterable<Filter>`

Returns
Type	Description
`Filter.Builder`

makeDelete(Key key)

public static Mutation.Builder makeDelete(Key key)

Parameter
Name	Description
`key`	`Key` the key of the entity to delete

Returns
Type	Description
`Mutation.Builder`	a mutation that will delete an entity

makeFilter(String property, PropertyFilter.Operator operator, Value value)

public static Filter.Builder makeFilter(String property, PropertyFilter.Operator operator, Value value)

Make a filter on a property for use in a query.

Parameters
Name	Description
`property`	`String`
`operator`	`PropertyFilter.Operator`
`value`	`Value`

Returns
Type	Description
`Filter.Builder`

makeFilter(String property, PropertyFilter.Operator operator, Value.Builder value)

public static Filter.Builder makeFilter(String property, PropertyFilter.Operator operator, Value.Builder value)

Make a filter on a property for use in a query.

Parameters
Name	Description
`property`	`String`
`operator`	`PropertyFilter.Operator`
`value`	`Value.Builder`

Returns
Type	Description
`Filter.Builder`

makeInsert(Entity entity)

public static Mutation.Builder makeInsert(Entity entity)

Parameter
Name	Description
`entity`	`Entity` the entity to insert

Returns
Type	Description
`Mutation.Builder`	a mutation that will insert an entity

makeKey(Object[] elements)

public static Key.Builder makeKey(Object[] elements)

Make a key from the specified path of kind/id-or-name pairs and/or Keys.

The id-or-name values must be either String, Long, Integer or Short.

The last id-or-name value may be omitted, in which case an entity without an id is created (for use with automatic id allocation).

The PartitionIds of all Keys in the path must be equal. The returned Key.Builder will use this PartitionId.

Parameter
Name	Description
`elements`	`Object[]`

Returns
Type	Description
`Key.Builder`

makeOrder(String property, PropertyOrder.Direction direction)

public static PropertyOrder.Builder makeOrder(String property, PropertyOrder.Direction direction)

Make a sort order for use in a query.

Parameters
Name	Description
`property`	`String`
`direction`	`PropertyOrder.Direction`

Returns
Type	Description
`PropertyOrder.Builder`

makePropertyReference(String propertyName)

public static PropertyReference.Builder makePropertyReference(String propertyName)

Make a property reference for use in a query.

Parameter
Name	Description
`propertyName`	`String`

Returns
Type	Description
`PropertyReference.Builder`

makeUpdate(Entity entity)

public static Mutation.Builder makeUpdate(Entity entity)

Parameter
Name	Description
`entity`	`Entity` the entity to update

Returns
Type	Description
`Mutation.Builder`	a mutation that will update an entity

makeUpsert(Entity entity)

public static Mutation.Builder makeUpsert(Entity entity)

Parameter
Name	Description
`entity`	`Entity` the entity to upsert

Returns
Type	Description
`Mutation.Builder`	a mutation that will upsert an entity

makeValue(boolean value)

public static Value.Builder makeValue(boolean value)

Make a boolean value.

Parameter
Name	Description
`value`	`boolean`

Returns
Type	Description
`Value.Builder`

makeValue(Entity entity)

public static Value.Builder makeValue(Entity entity)

Make an entity value.

Parameter
Name	Description
`entity`	`Entity`

Returns
Type	Description
`Value.Builder`

makeValue(Entity.Builder entity)

public static Value.Builder makeValue(Entity.Builder entity)

Make a entity value.

Parameter
Name	Description
`entity`	`Entity.Builder`

Returns
Type	Description
`Value.Builder`

makeValue(Key key)

public static Value.Builder makeValue(Key key)

Make a key value.

Parameter
Name	Description
`key`	`Key`

Returns
Type	Description
`Value.Builder`

makeValue(Key.Builder key)

public static Value.Builder makeValue(Key.Builder key)

Make a key value.

Parameter
Name	Description
`key`	`Key.Builder`

Returns
Type	Description
`Value.Builder`

makeValue(Value value1, Value value2, Value[] rest)

public static Value.Builder makeValue(Value value1, Value value2, Value[] rest)

Make a list value containing the specified values.

Parameters
Name	Description
`value1`	`Value`
`value2`	`Value`
`rest`	`Value[]`

Returns
Type	Description
`Value.Builder`

makeValue(Value.Builder value1, Value.Builder value2, Value.Builder[] rest)

public static Value.Builder makeValue(Value.Builder value1, Value.Builder value2, Value.Builder[] rest)

Make an array value containing the specified values.

Parameters
Name	Description
`value1`	`Value.Builder`
`value2`	`Value.Builder`
`rest`	`Builder[]`

Returns
Type	Description
`Value.Builder`

makeValue(ByteString blob)

public static Value.Builder makeValue(ByteString blob)

Make a ByteString value.

Parameter
Name	Description
`blob`	`ByteString`

Returns
Type	Description
`Value.Builder`

makeValue(LatLng value)

public static Value.Builder makeValue(LatLng value)

Makes a GeoPoint value.

Parameter
Name	Description
`value`	`com.google.type.LatLng`

Returns
Type	Description
`Value.Builder`

makeValue(LatLng.Builder value)

public static Value.Builder makeValue(LatLng.Builder value)

Makes a GeoPoint value.

Parameter
Name	Description
`value`	`com.google.type.LatLng.Builder`

Returns
Type	Description
`Value.Builder`

makeValue(double value)

public static Value.Builder makeValue(double value)

Make a floating point value.

Parameter
Name	Description
`value`	`double`

Returns
Type	Description
`Value.Builder`

makeValue(Iterable<Value> values)

public static Value.Builder makeValue(Iterable<Value> values)

Make an array value containing the specified values.

Parameter
Name	Description
`values`	`Iterable<Value>`

Returns
Type	Description
`Value.Builder`

makeValue(String value)

public static Value.Builder makeValue(String value)

Make a string value.

Parameter
Name	Description
`value`	`String`

Returns
Type	Description
`Value.Builder`

makeValue(Date date)

public static Value.Builder makeValue(Date date)

Make a timestamp value given a date.

Parameter
Name	Description
`date`	`Date`

Returns
Type	Description
`Value.Builder`

makeValue(long key)

public static Value.Builder makeValue(long key)

Make an integer value.

Parameter
Name	Description
`key`	`long`

Returns
Type	Description
`Value.Builder`

toDate(Value value)

public static Date toDate(Value value)

Convert a timestamp value into a Date clipping off the microseconds.

Parameter
Name	Description
`value`	`Value` a timestamp value to convert

Returns
Type	Description
`Date`	the resulting Date