Package org.apache.zookeeper.common

Class AtomicFileOutputStream

  • All Implemented Interfaces:
    java.io.Closeable, java.io.Flushable, java.lang.AutoCloseable
    public class AtomicFileOutputStream
extends java.io.FilterOutputStream
    A FileOutputStream that has the property that it will only show up at its destination once it has been entirely written and flushed to disk. While being written, it will use a .tmp suffix. When the output stream is closed, it is flushed, fsynced, and will be moved into place, overwriting any file that already exists at that location. NOTE: on Windows platforms, it will not atomically replace the target file - instead the target file is deleted before this one is moved into place.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void abort()
      Close the atomic file, but do not "commit" the temporary file on top of the destination.
      void close()  
      void write​(byte[] b, int off, int len)
      The default write method in FilterOutputStream does not call the write method of its underlying input stream with the same arguments.

      • Methods inherited from class java.io.FilterOutputStream

        flush, write, write

      • Methods inherited from class java.io.OutputStream

        nullOutputStream

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • AtomicFileOutputStream

        public AtomicFileOutputStream​(java.io.File f)
                       throws java.io.FileNotFoundException
        Throws:
        java.io.FileNotFoundException

    • Method Detail

      • write

        public void write​(byte[] b,
                  int off,
                  int len)
           throws java.io.IOException
        The default write method in FilterOutputStream does not call the write method of its underlying input stream with the same arguments. Instead it writes the data byte by byte, override it here to make it more efficient.
        Overrides:
        write in class java.io.FilterOutputStream
        Throws:
        java.io.IOException

      • close

        public void close()
           throws java.io.IOException
        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface java.io.Closeable
        Overrides:
        close in class java.io.FilterOutputStream
        Throws:
        java.io.IOException

      • abort

        public void abort()
        Close the atomic file, but do not "commit" the temporary file on top of the destination. This should be used if there is a failure in writing.