Package org.apache.hadoop.fs

Class FSDataOutputStreamBuilder<S extends FSDataOutputStream,B extends FSDataOutputStreamBuilder<S,B>>

java.lang.Object
org.apache.hadoop.fs.impl.AbstractFSBuilderImpl<S,B>
org.apache.hadoop.fs.FSDataOutputStreamBuilder<S,B>
All Implemented Interfaces:
FSBuilder<S,B>
@Public @Evolving public abstract class FSDataOutputStreamBuilder<S extends FSDataOutputStream,B extends FSDataOutputStreamBuilder<S,B>> extends AbstractFSBuilderImpl<S,B>
Builder for FSDataOutputStream and its subclasses. It is used to create FSDataOutputStream when creating a new file or appending an existing file on FileSystem. By default, it does not create parent directory that do not exist. FileSystem.createNonRecursive(Path, boolean, int, short, long, Progressable). To create missing parent directory, use recursive(). To be more generic, AbstractFSBuilderImpl.opt(String, int) and AbstractFSBuilderImpl.must(String, int) variants provide implementation-agnostic way to customize the builder. Each FS-specific builder implementation can interpret the FS-specific options accordingly, for example: // Don't if (fs instanceof FooFileSystem) { FooFileSystem fs = (FooFileSystem) fs; OutputStream out = dfs.createFile(path) .optionA() .optionB("value") .cache() .build() } else if (fs instanceof BarFileSystem) { ... } // Do OutputStream out = fs.createFile(path) .permission(perm) .bufferSize(bufSize) .opt("foofs:option.a", true) .opt("foofs:option.b", "value") .opt("barfs:cache", true) .must("foofs:cache", true) .must("barfs:cache-size", 256 * 1024 * 1024) .build(); If the option is not related to the file system, the option will be ignored. If the option is must, but not supported by the file system, a IllegalArgumentException will be thrown.

  • Constructor Details

    • FSDataOutputStreamBuilder

      protected FSDataOutputStreamBuilder(@Nonnull FileSystem fileSystem, @Nonnull Path p)
      Constructor.
      Parameters:
      fileSystem - file system.
      p - the path.

  • Method Details

    • getThisBuilder

      public abstract B getThisBuilder()
      Return the concrete implementation of the builder instance.
      Overrides:
      getThisBuilder in class AbstractFSBuilderImpl<S extends FSDataOutputStream,B extends FSDataOutputStreamBuilder<S,B>>
      Returns:
      this object, typecast

    • getFS

      protected FileSystem getFS()

    • getPermission

      protected FsPermission getPermission()

    • permission

      public B permission(@Nonnull FsPermission perm)
      Set permission for the file.
      Parameters:
      perm - permission.
      Returns:
      B Generics Type.

    • getBufferSize

      protected int getBufferSize()

    • bufferSize

      public B bufferSize(int bufSize)
      Set the size of the buffer to be used.
      Parameters:
      bufSize - buffer size.
      Returns:
      Generics Type B.

    • getReplication

      protected short getReplication()

    • replication

      public B replication(short replica)
      Set replication factor.
      Parameters:
      replica - replica.
      Returns:
      Generics Type B.

    • getBlockSize

      protected long getBlockSize()

    • blockSize

      public B blockSize(long blkSize)
      Set block size.
      Parameters:
      blkSize - block size.
      Returns:
      B Generics Type.

    • isRecursive

      protected boolean isRecursive()
      Return true to create the parent directories if they do not exist.
      Returns:
      if create the parent directories if they do not exist true,not false.

    • recursive

      public B recursive()
      Create the parent directory if they do not exist.
      Returns:
      B Generics Type.

    • getProgress

      protected Progressable getProgress()

    • progress

      public B progress(@Nonnull Progressable prog)
      Set the facility of reporting progress.
      Parameters:
      prog - progress.
      Returns:
      B Generics Type.

    • getFlags

      protected EnumSet<CreateFlag> getFlags()

    • create

      public B create()
      Create an FSDataOutputStream at the specified path.
      Returns:
      return Generics Type B.

    • overwrite

      public B overwrite(boolean overwrite)
      Set to true to overwrite the existing file. Set it to false, an exception will be thrown when calling build() if the file exists.
      Parameters:
      overwrite - overrite.
      Returns:
      Generics Type B.

    • append

      public B append()
      Append to an existing file (optional operation).
      Returns:
      Generics Type B.

    • getChecksumOpt

      protected org.apache.hadoop.fs.Options.ChecksumOpt getChecksumOpt()

    • checksumOpt

      public B checksumOpt(@Nonnull org.apache.hadoop.fs.Options.ChecksumOpt chksumOpt)
      Set checksum opt.
      Parameters:
      chksumOpt - check sum opt.
      Returns:
      Generics Type B.

    • build

      public abstract S build() throws IllegalArgumentException, IOException
      Create the FSDataOutputStream to write on the file system.
      Returns:
      generic type S.
      Throws:
      IllegalArgumentException - if the parameters are not valid.
      IOException - on errors when file system creates or appends the file.