Class ResettableInputStream

All Implemented Interfaces:
Closeable, AutoCloseable, Releasable

@NotThreadSafe public class ResettableInputStream extends ReleasableInputStream
A mark-and-resettable input stream that can be used on files or file input streams. In particular, a ResettableInputStream allows the close operation to be disabled via ReleasableInputStream.disableClose() (to avoid accidentally being closed). This is necessary when such input stream needs to be marked-and-reset multiple times but only as long as the stream has not been closed.

The creator of this input stream should therefore always call ReleasableInputStream.release() in a finally block to truly release the underlying resources.

See Also:
  • Constructor Details

    • ResettableInputStream

      public ResettableInputStream(File file) throws IOException
      Parameters:
      file - must not be null. Upon successful construction the the file will be opened with an input stream automatically marked at the starting position of the given file.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

      Throws:
      IOException
    • ResettableInputStream

      public ResettableInputStream(FileInputStream fis) throws IOException

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

      Parameters:
      fis - file input stream; must not be null. Upon successful construction the input stream will be automatically marked at the current position of the given file input stream.
      Throws:
      IOException
  • Method Details

    • newResettableInputStream

      public static ResettableInputStream newResettableInputStream(File file)
      Convenient factory method to construct a new resettable input stream for the given file, converting any IOException into SdkClientException.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

    • newResettableInputStream

      public static ResettableInputStream newResettableInputStream(File file, String errmsg)
      Convenient factory method to construct a new resettable input stream for the given file, converting any IOException into SdkClientException with the given error message.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

    • newResettableInputStream

      public static ResettableInputStream newResettableInputStream(FileInputStream fis)
      Convenient factory method to construct a new resettable input stream for the given file input stream, converting any IOException into SdkClientException.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

    • newResettableInputStream

      public static ResettableInputStream newResettableInputStream(FileInputStream fis, String errmsg)
      Convenient factory method to construct a new resettable input stream for the given file input stream, converting any IOException into SdkClientException with the given error message.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

    • markSupported

      public final boolean markSupported()
      Overrides:
      markSupported in class SdkFilterInputStream
    • mark

      public void mark(int ignored)
      Marks the current position in this input stream. A subsequent call to the reset method repositions this stream at the last marked position so that subsequent reads re-read the same bytes. This method works as long as the underlying file has not been closed.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

      Overrides:
      mark in class SdkFilterInputStream
      Parameters:
      ignored - ignored
    • reset

      public void reset() throws IOException
      Repositions this stream to the position at the time the mark method was last called on this input stream. This method works as long as the underlying file has not been closed.

      Note the creation of a ResettableInputStream would entail physically opening a file. If the opened file is meant to be closed only (in a finally block) by the very same code block that created it, then it is necessary that the release method must not be called while the execution is made in other stack frames. In such case, as other stack frames may inadvertently or indirectly call the close method of the stream, the creator of the stream would need to explicitly disable the accidental closing via ReleasableInputStream.disableClose(), so that the release method becomes the only way to truly close the opened file.

      Overrides:
      reset in class SdkFilterInputStream
      Throws:
      IOException
    • available

      public int available() throws IOException
      Overrides:
      available in class SdkFilterInputStream
      Throws:
      IOException
    • read

      public int read() throws IOException
      Overrides:
      read in class SdkFilterInputStream
      Throws:
      IOException
    • skip

      public long skip(long n) throws IOException
      Overrides:
      skip in class SdkFilterInputStream
      Throws:
      IOException
    • read

      public int read(byte[] arg0, int arg1, int arg2) throws IOException
      Overrides:
      read in class SdkFilterInputStream
      Throws:
      IOException
    • getFile

      public File getFile()
      Returns the underlying file, if known; or null if not;