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package root
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root
package com
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root
package here
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com
package platform
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here
package data
Definition Classes
platform
package processing
This package provides the Data Processing Library for building distributed data processing applications.
This package provides the Data Processing Library for building distributed data processing applications.
A Runner both implements the interface with the environment for an application to run, and starts the application. The application, in turn, is driven by a Driver, that controls and performs the distributed processing.
Choose a Runner best suited for the environment where the application runs.
The Driver performs one of more tasks which read layers from input catalogs and write to one or more layers of an output catalog.
The main entry point in the processing library is the com.here.platform.data.processing.driver.DriverBuilder class where you can add different kinds of tasks to the driver. The driver runs the tasks, and commits the final results to the output catalog.
Tasks are implemented using one or more compilers.
The simplest compiler is the direct compiler which maps each input tile to N output tiles. The application needs to define com.here.platform.data.processing.compiler.Direct1ToNCompiler.
Other more complex compilation patterns are based on some kind of dependency tracking between input partitions and output partitions.
The processing Library supports the following patterns:
- com.here.platform.data.processing.compiler.NonIncrementalCompiler: non-incremental compilation only - com.here.platform.data.processing.compiler.DepCompiler: non-incremental dependency calculation and incremental compilation - com.here.platform.data.processing.compiler.IncrementalDepCompiler: incremental dependency calculation and compilation - com.here.platform.data.processing.compiler.Direct1ToNCompiler: incremental compilation where every output tile depends only on one input tile, and this mapping is independent from tile content - com.here.platform.data.processing.compiler.DirectMToNCompiler: incremental compilation where every output tile depends on multiple input tiles, and this mapping is independent from tile content - com.here.platform.data.processing.compiler.MapGroupCompiler: incremental compilation where every output tile can depend on multiple input tiles, and this mapping depend on the tile content - com.here.platform.data.processing.compiler.RefTreeCompiler: fully-managed two phases incremental compilation that can resolve references between input partitions. Input/Output dependency management is implemented and the developer doesn't need to provide this logic
The application's main object normally mixes in the a runner trait (like PipelineRunner) to setup the Driver, and interfaces with the environment where the application is run. See the Main classes in the example compilers for more details.
com.here.platform.data.processing.catalog, com.here.platform.data.processing.blobstore, and com.here.platform.data.processing.publisher contain utilities for accessing catalogs and payloads in a Spark-friendly way, providing an RDD-based abstraction over data and metadata. These classes are used by the processing library, but can also be used independently.
Definition Classes
data
package blobstore
Contains an abstract interface used to access BlobStore.
Contains an abstract interface used to access BlobStore.
Obtain the retriever and uploader for a catalog directly from the com.here.platform.data.processing.catalog.Catalog instance.
Definition Classes
processing
package caching
Definition Classes
blobstore
CachingMappingRetriever
CachingRetriever

com.here.platform.data.processing.blobstore.caching

CachingMappingRetriever

Companion object CachingMappingRetriever

class CachingMappingRetriever[T <: AnyRef] extends Serializable with ContextLogging

A wrapper for the Retriever class, that applies a mapping function on the retrieved payloads and caches the resulting values.

T: The type of the decoded payload, after applying the mapping function.

Note: A CachingMappingRetriever can be only created from the Spark driver. If a CachingMappingRetriever is created from inside a Spark worker node, an exception is thrown.

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ContextLogging, Serializable, AnyRef, Any

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new CachingMappingRetriever(retriever: Retriever, mapFn: (Key, Payload) => T, filter: CacheFilter = CachingMappingRetriever.noFilter, factory: CacheFactory[T] = GuavaCache.cacheFactory[(Key, Meta), T](), statistics: Option[Statistics] = None)
retriever
The wrapped Retriever.
mapFn
A decoding function applied to the retrieved payloads and their keys.
filter
A predicate used to cache only the partitions for which the predicate returns true. If not specified, all partitions are cached.
factory
A functions that returns a com.here.platform.data.processing.utils.cache.Cache. If not specified com.here.platform.data.processing.utils.cache.GuavaCache.cacheFactory is used.
statistics
An optional com.here.platform.data.processing.statistics.Statistics object. If defined, statistics about the number of cache requests and misses are recorded.

Value Members

final def !=(arg0: Any): Boolean
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final def ##: Int
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final def ==(arg0: Any): Boolean
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final def asInstanceOf[T0]: T0
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def classForLogger: Class[_]
Override this to change the class that is displayed in logs.
Override this to change the class that is displayed in logs.
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def clone(): AnyRef
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protected[lang]
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@throws(classOf[java.lang.CloneNotSupportedException]) @IntrinsicCandidate() @native()
final def eq(arg0: AnyRef): Boolean
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def equals(arg0: AnyRef): Boolean
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final def getClass(): Class[_ <: AnyRef]
Definition Classes
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@IntrinsicCandidate() @native()
def getPayloadAndMap(key: Key, meta: Meta, file: File): T
Returns the decoded value associated with the key-meta pair in this cache.
Returns the decoded value associated with the key-meta pair in this cache. If the value is not cached, it is retrieved with the wrapped retriever and decoded with the mapping function. If filter returns false for the key-meta pair, the cache is not used. This version uses a file to store the content of the payload when a miss occurs. The transformed payload is still stored in memory though.
key
The partition key.
meta
The partition metadata.
file
The file where the retrieved payload must be stored.
returns
The decoded payload.
Note
In case of a cache hit, the file is not created or written. It's the caller's responsibility to delete the file when it's no longer needed.
def getPayloadAndMap(key: Key, meta: Meta): T
Returns the decoded value associated with the key-meta pair in this cache.
Returns the decoded value associated with the key-meta pair in this cache. If the value is not cached, it is retrieved with the wrapped retriever and decoded with the mapping function. If filter returns false for the key-meta pair, the cache is not used.
key
The partition key.
meta
The partition metadata.
returns
The decoded payload.
def hashCode(): Int
Definition Classes
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@IntrinsicCandidate() @native()
final def isInstanceOf[T0]: Boolean
Definition Classes
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final lazy val logger: ContextAwareLogger
The logger to use for normal and context-aware messages.
The logger to use for normal and context-aware messages.
Attributes
protected
Definition Classes
ContextLogging
final def ne(arg0: AnyRef): Boolean
Definition Classes
AnyRef
final def notify(): Unit
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@IntrinsicCandidate() @native()
final def notifyAll(): Unit
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@IntrinsicCandidate() @native()
final def synchronized[T0](arg0: => T0): T0
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def toString(): String
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final def wait(arg0: Long, arg1: Int): Unit
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@throws(classOf[java.lang.InterruptedException])
final def wait(arg0: Long): Unit
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final def wait(): Unit
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@throws(classOf[java.lang.InterruptedException])

Deprecated Value Members

def finalize(): Unit
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protected[lang]
Definition Classes
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@throws(classOf[java.lang.Throwable]) @Deprecated
Deprecated
(Since version 9)

Packages

CachingMappingRetriever

Companion object CachingMappingRetriever

class CachingMappingRetriever[T <: AnyRef] extends Serializable with ContextLogging

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CachingMappingRetriever

Companion object CachingMappingRetriever

class CachingMappingRetriever[T <: AnyRef] extends Serializable with ContextLogging

Instance Constructors

Value Members

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Inherited from ContextLogging

Inherited from Serializable

Inherited from AnyRef

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CachingMappingRetriever