Package org.apache.commons.net.io

# Class Util

java.lang.Object
org.apache.commons.net.io.Util

public final class Util extends Object
The Util class cannot be instantiated and stores short static convenience methods that are often quite useful.

See Also:
  - `CopyStreamException`
  - `CopyStreamListener`
  - `CopyStreamAdapter`

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final int`
  `DEFAULT_COPY_BUFFER_SIZE`
  The default buffer size (1024) used by `copyStream` and `copyReader` and by the copyReader/copyStream methods if a zero or negative buffer size is supplied.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static void`
  `closeQuietly(Closeable closeable)`
  Closes the object quietly, catching rather than throwing IOException.
  `static void`
  `closeQuietly(Socket socket)`
  Closes the socket quietly, catching rather than throwing IOException.
  `static long`
  `copyReader(Reader source, Writer dest)`
  Same as `copyReader(source, dest, DEFAULT_COPY_BUFFER_SIZE);`
  `static long`
  `copyReader(Reader source, Writer dest, int bufferSize)`
  Copies the contents of a Reader to a Writer using a copy buffer of a given size.
  `static long`
  `copyReader(Reader source, Writer dest, int bufferSize, long streamSize, CopyStreamListener listener)`
  Copies the contents of a Reader to a Writer using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination.
  `static long`
  `copyStream(InputStream source, OutputStream dest)`
  Same as `copyStream(source, dest, DEFAULT_COPY_BUFFER_SIZE);`
  `static long`
  `copyStream(InputStream source, OutputStream dest, int bufferSize)`
  Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size.
  `static long`
  `copyStream(InputStream source, OutputStream dest, int bufferSize, long streamSize, CopyStreamListener listener)`
  Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination.
  `static long`
  `copyStream(InputStream source, OutputStream dest, int bufferSize, long streamSize, CopyStreamListener listener, boolean flush)`
  Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination.

  ### Methods inherited from class java.lang.Object

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

- ## Field Details

  - ### DEFAULT_COPY_BUFFER_SIZE

    public static final int DEFAULT_COPY_BUFFER_SIZE
    The default buffer size (1024) used by `copyStream` and `copyReader` and by the copyReader/copyStream methods if a zero or negative buffer size is supplied.
    See Also:
      - Constant Field Values

- ## Method Details

  - ### closeQuietly

    public static void closeQuietly(Closeable closeable)
    Closes the object quietly, catching rather than throwing IOException. Intended for use from finally blocks.
    Parameters:
      `closeable` - the object to close, may be `null`
    Since:
      3.0

  - ### closeQuietly

    public static void closeQuietly(Socket socket)
    Closes the socket quietly, catching rather than throwing IOException. Intended for use from finally blocks.
    Parameters:
      `socket` - the socket to close, may be `null`
    Since:
      3.0

  - ### copyReader

    public static long copyReader(Reader source, Writer dest) throws CopyStreamException
    Same as `copyReader(source, dest, DEFAULT_COPY_BUFFER_SIZE);`
    Parameters:
      `source` - where to copy from
      `dest` - where to copy to
    Returns:
      number of bytes copied
    Throws:
      `CopyStreamException` - on error

  - ### copyReader

    public static long copyReader(Reader source, Writer dest, int bufferSize) throws CopyStreamException
    Copies the contents of a Reader to a Writer using a copy buffer of a given size. The contents of the Reader are read until its end is reached, but neither the source nor the destination are closed. You must do this yourself outside the method call. The number of characters read/written is returned.
    Parameters:
      `source` - The source Reader.
      `dest` - The destination writer.
      `bufferSize` - The number of characters to buffer during the copy. A zero or negative value means to use `DEFAULT_COPY_BUFFER_SIZE`.
    Returns:
      The number of characters read/written in the copy operation.
    Throws:
      `CopyStreamException` - If an error occurs while reading from the source or writing to the destination. The CopyStreamException will contain the number of bytes confirmed to have been transferred before an IOException occurred, and it will also contain the IOException that caused the error. These values can be retrieved with the CopyStreamException getTotalBytesTransferred() and getIOException() methods.

  - ### copyReader

    public static long copyReader(Reader source, Writer dest, int bufferSize, long streamSize, CopyStreamListener listener) throws CopyStreamException
    Copies the contents of a Reader to a Writer using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination. If you wish to notify more than one listener you should use a CopyStreamAdapter as the listener and register the additional listeners with the CopyStreamAdapter.

    The contents of the Reader are read until its end is reached, but neither the source nor the destination are closed. You must do this yourself outside the method call. The number of characters read/written is returned.

    Parameters:
      `source` - The source Reader.
      `dest` - The destination writer.
      `bufferSize` - The number of characters to buffer during the copy. A zero or negative value means to use `DEFAULT_COPY_BUFFER_SIZE`.
      `streamSize` - The number of characters in the stream being copied. Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown. Not currently used (though it is passed to `CopyStreamListener.bytesTransferred(long, int, long)`
      `listener` - The CopyStreamListener to notify of progress. If this parameter is null, notification is not attempted.
    Returns:
      The number of characters read/written in the copy operation.
    Throws:
      `CopyStreamException` - If an error occurs while reading from the source or writing to the destination. The CopyStreamException will contain the number of bytes confirmed to have been transferred before an IOException occurred, and it will also contain the IOException that caused the error. These values can be retrieved with the CopyStreamException getTotalBytesTransferred() and getIOException() methods.

  - ### copyStream

    public static long copyStream(InputStream source, OutputStream dest) throws CopyStreamException
    Same as `copyStream(source, dest, DEFAULT_COPY_BUFFER_SIZE);`
    Parameters:
      `source` - where to copy from
      `dest` - where to copy to
    Returns:
      number of bytes copied
    Throws:
      `CopyStreamException` - on error

  - ### copyStream

    public static long copyStream(InputStream source, OutputStream dest, int bufferSize) throws CopyStreamException
    Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size. The contents of the InputStream are read until the end of the stream is reached, but neither the source nor the destination are closed. You must do this yourself outside the method call. The number of bytes read/written is returned.
    Parameters:
      `source` - The source InputStream.
      `dest` - The destination OutputStream.
      `bufferSize` - The number of bytes to buffer during the copy. A zero or negative value means to use `DEFAULT_COPY_BUFFER_SIZE`.
    Returns:
      The number of bytes read/written in the copy operation.
    Throws:
      `CopyStreamException` - If an error occurs while reading from the source or writing to the destination. The CopyStreamException will contain the number of bytes confirmed to have been transferred before an IOException occurred, and it will also contain the IOException that caused the error. These values can be retrieved with the CopyStreamException getTotalBytesTransferred() and getIOException() methods.

  - ### copyStream

    public static long copyStream(InputStream source, OutputStream dest, int bufferSize, long streamSize, CopyStreamListener listener) throws CopyStreamException
    Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination. If you wish to notify more than one listener you should use a CopyStreamAdapter as the listener and register the additional listeners with the CopyStreamAdapter.

    The contents of the InputStream are read until the end of the stream is reached, but neither the source nor the destination are closed. You must do this yourself outside the method call. The number of bytes read/written is returned.

    Parameters:
      `source` - The source InputStream.
      `dest` - The destination OutputStream.
      `bufferSize` - The number of bytes to buffer during the copy. A zero or negative value means to use `DEFAULT_COPY_BUFFER_SIZE`.
      `streamSize` - The number of bytes in the stream being copied. Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown. Not currently used (though it is passed to `CopyStreamListener.bytesTransferred(long, int, long)`
      `listener` - The CopyStreamListener to notify of progress. If this parameter is null, notification is not attempted.
    Returns:
      number of bytes read/written
    Throws:
      `CopyStreamException` - If an error occurs while reading from the source or writing to the destination. The CopyStreamException will contain the number of bytes confirmed to have been transferred before an IOException occurred, and it will also contain the IOException that caused the error. These values can be retrieved with the CopyStreamException getTotalBytesTransferred() and getIOException() methods.

  - ### copyStream

    public static long copyStream(InputStream source, OutputStream dest, int bufferSize, long streamSize, CopyStreamListener listener, boolean flush) throws CopyStreamException
    Copies the contents of an InputStream to an OutputStream using a copy buffer of a given size and notifies the provided CopyStreamListener of the progress of the copy operation by calling its bytesTransferred(long, int) method after each write to the destination. If you wish to notify more than one listener you should use a CopyStreamAdapter as the listener and register the additional listeners with the CopyStreamAdapter.

    The contents of the InputStream are read until the end of the stream is reached, but neither the source nor the destination are closed. You must do this yourself outside the method call. The number of bytes read/written is returned.

    Parameters:
      `source` - The source InputStream.
      `dest` - The destination OutputStream.
      `bufferSize` - The number of bytes to buffer during the copy. A zero or negative value means to use `DEFAULT_COPY_BUFFER_SIZE`.
      `streamSize` - The number of bytes in the stream being copied. Should be set to CopyStreamEvent.UNKNOWN_STREAM_SIZE if unknown. Not currently used (though it is passed to `CopyStreamListener.bytesTransferred(long, int, long)`
      `listener` - The CopyStreamListener to notify of progress. If this parameter is null, notification is not attempted.
      `flush` - Whether to flush the output stream after every write. This is necessary for interactive sessions that rely on buffered streams. If you don't flush, the data will stay in the stream buffer.
    Returns:
      number of bytes read/written
    Throws:
      `CopyStreamException` - If an error occurs while reading from the source or writing to the destination. The CopyStreamException will contain the number of bytes confirmed to have been transferred before an IOException occurred, and it will also contain the IOException that caused the error. These values can be retrieved with the CopyStreamException getTotalBytesTransferred() and getIOException() methods.