Package akka.stream.javadsl

Class FileIO

  • public class FileIO
extends java.lang.Object
    Java API: Factories to create sinks and sources from files

    • Constructor Summary

      Constructors 
      Constructor Description
      FileIO()  

    • Method Summary

      All Methods Static Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromFile​(java.io.File f)
      Deprecated.
      Use `fromPath` instead.
      static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromFile​(java.io.File f, int chunkSize)
      Deprecated.
      Use `fromPath` instead.
      static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f)
      Creates a Source from a files contents.
      static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f, int chunkSize)
      Creates a synchronous Source from a files contents.
      static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f, int chunkSize, long startPosition)
      Creates a synchronous Source from a files contents.
      static Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toFile​(java.io.File f)
      Deprecated.
      Use `toPath` instead.
      static <Opt extends java.nio.file.OpenOption>
      Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>>      		 toFile​(java.io.File f, java.util.Set<Opt> options)
      Deprecated.
      Use `toPath` instead.
      static Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toPath​(java.nio.file.Path f)
      Creates a Sink that writes incoming ByteString elements to the given file path.
      static <Opt extends java.nio.file.OpenOption>
      Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>>      		 toPath​(java.nio.file.Path f, java.util.Set<Opt> options)
      Creates a Sink that writes incoming ByteString elements to the given file path.
      static <Opt extends java.nio.file.OpenOption>
      Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>>      		 toPath​(java.nio.file.Path f, java.util.Set<Opt> options, long startPosition)
      Creates a Sink that writes incoming ByteString elements to the given file path.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • FileIO

        public FileIO()

    • Method Detail

      • toFile

        public static Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toFile​(java.io.File f)
        Deprecated.
        Use `toPath` instead. Since 2.4.5.
        Creates a Sink that writes incoming ByteString elements to the given file. Overwrites existing files by truncating their contents, if you want to append to an existing file use {@link toFile(File, util.Set[OpenOption])} with java.nio.file.StandardOpenOption.APPEND.

        Materializes a CompletionStage of IOResult that will be completed with the size of the file (in bytes) at the streams completion, and a possible exception if IO operation was not completed successfully.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        Parameters:
        f - The file to write to

      • toPath

        public static Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toPath​(java.nio.file.Path f)
        Creates a Sink that writes incoming ByteString elements to the given file path. Overwrites existing files by truncating their contents, if you want to append to an existing file {@link toPath(Path, util.Set[OpenOption])} with java.nio.file.StandardOpenOption.APPEND.

        Materializes a CompletionStage of IOResult that will be completed with the size of the file (in bytes) at the streams completion, and a possible exception if IO operation was not completed successfully.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        Accepts as arguments a set of StandardOpenOption, which will determine the underlying behavior when writing the file. If java.nio.file.StandardOpenOption.SYNC is provided, every update to the file's content be written synchronously to the underlying storage device. Otherwise (the default), the write will be written to the storage device asynchronously by the OS, and may not be stored durably on the storage device at the time the stream completes.

        Parameters:
        f - The file path to write to

      • toFile

        public static <Opt extends java.nio.file.OpenOption> Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toFile​(java.io.File f,
                                                                                                                                  java.util.Set<Opt> options)
        Deprecated.
        Use `toPath` instead. Since 2.4.5.
        Creates a Sink that writes incoming ByteString elements to the given file.

        Materializes a CompletionStage of IOResult that will be completed with the size of the file (in bytes) at the streams completion, and a possible exception if IO operation was not completed successfully.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        Parameters:
        f - The file to write to
        options - File open options, see StandardOpenOption

      • toPath

        public static <Opt extends java.nio.file.OpenOption> Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toPath​(java.nio.file.Path f,
                                                                                                                                  java.util.Set<Opt> options)
        Creates a Sink that writes incoming ByteString elements to the given file path.

        Materializes a CompletionStage of IOResult that will be completed with the size of the file (in bytes) at the streams completion, and a possible exception if IO operation was not completed successfully.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        Accepts as arguments a set of StandardOpenOption, which will determine the underlying behavior when writing the file. If java.nio.file.StandardOpenOption.SYNC is provided, every update to the file's content be written synchronously to the underlying storage device. Otherwise (the default), the write will be written to the storage device asynchronously by the OS, and may not be stored durably on the storage device at the time the stream completes.

        Parameters:
        f - The file path to write to
        options - File open options, see StandardOpenOption

      • toPath

        public static <Opt extends java.nio.file.OpenOption> Sink<ByteString,​java.util.concurrent.CompletionStage<IOResult>> toPath​(java.nio.file.Path f,
                                                                                                                                  java.util.Set<Opt> options,
                                                                                                                                  long startPosition)
        Creates a Sink that writes incoming ByteString elements to the given file path.

        Materializes a CompletionStage of IOResult that will be completed with the size of the file (in bytes) at the streams completion, and a possible exception if IO operation was not completed successfully.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        Accepts as arguments a set of StandardOpenOption, which will determine the underlying behavior when writing the file. If java.nio.file.StandardOpenOption.SYNC is provided, every update to the file's content be written synchronously to the underlying storage device. Otherwise (the default), the write will be written to the storage device asynchronously. by the OS, and may not be stored durably on the storage device at the time the stream completes.

        Parameters:
        f - The file path to write to
        options - File open options, see StandardOpenOption
        startPosition - startPosition the start position to read from, defaults to 0

      • fromFile

        public static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromFile​(java.io.File f)
        Deprecated.
        Use `fromPath` instead. Since 2.4.5.
        Creates a Source from a files contents. Emitted elements are ByteString elements, chunked by default by 8192 bytes, except the last element, which will be up to 8192 in size.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        It materializes a CompletionStage of IOResult containing the number of bytes read from the source file upon completion, and a possible exception if IO operation was not completed successfully. Note that bytes having been read by the source does not give any guarantee that the bytes were seen by downstream stages.

        Parameters:
        f - the file to read from

      • fromPath

        public static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f)
        Creates a Source from a files contents. Emitted elements are ByteString elements, chunked by default by 8192 bytes, except the last element, which will be up to 8192 in size.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        It materializes a CompletionStage of IOResult containing the number of bytes read from the source file upon completion, and a possible exception if IO operation was not completed successfully. Note that bytes having been read by the source does not give any guarantee that the bytes were seen by downstream stages.

        It is not possible to read FIFOs, also known as named pipes, with fromPath, trying to do so will potentially first block and then fail the stream.

        Parameters:
        f - the file path to read from

      • fromFile

        public static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromFile​(java.io.File f,
                                                                                               int chunkSize)
        Deprecated.
        Use `fromPath` instead. Since 2.4.5.
        Creates a synchronous Source from a files contents. Emitted elements are chunkSize sized ByteString elements, except the last element, which will be up to chunkSize in size.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        It materializes a CompletionStage of IOResult containing the number of bytes read from the source file upon completion, and a possible exception if IO operation was not completed successfully. Note that bytes having been read by the source does not give any guarantee that the bytes were seen by downstream stages.

        Parameters:
        f - the file to read from
        chunkSize - the size of each read operation

      • fromPath

        public static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f,
                                                                                               int chunkSize)
        Creates a synchronous Source from a files contents. Emitted elements are chunkSize sized ByteString elements, except the last element, which will be up to chunkSize in size.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        It materializes a CompletionStage of IOResult containing the number of bytes read from the source file upon completion, and a possible exception if IO operation was not completed successfully. Note that bytes having been read by the source does not give any guarantee that the bytes were seen by downstream stages.

        It is not possible to read FIFOs, also known as named pipes, with fromPath, trying to do so will potentially first block and then fail the stream.

        Parameters:
        f - the file path to read from
        chunkSize - the size of each read operation

      • fromPath

        public static Source<ByteString,​java.util.concurrent.CompletionStage<IOResult>> fromPath​(java.nio.file.Path f,
                                                                                               int chunkSize,
                                                                                               long startPosition)
        Creates a synchronous Source from a files contents. Emitted elements are chunkSize sized ByteString elements, except the last element, which will be up to chunkSize in size.

        You can configure the default dispatcher for this Source by changing the akka.stream.materializer.blocking-io-dispatcher or set it for a given Source by using ActorAttributes.

        It materializes a CompletionStage of IOResult containing the number of bytes read from the source file upon completion, and a possible exception if IO operation was not completed successfully. Note that bytes having been read by the source does not give any guarantee that the bytes were seen by downstream stages.

        Parameters:
        f - the file path to read from
        chunkSize - the size of each read operation
        startPosition - startPosition the start position to read from, defaults to 0