1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
5. Field Details
   1. out
6. Constructor Details
   1. FilterOutputStream(OutputStream)
7. Method Details
   1. write(int)
   2. write(byte[])
   3. write(byte[], int, int)
   4. flush()
   5. close()

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

BufferedOutputStream, CheckedOutputStream, CipherOutputStream, DataOutputStream, DeflaterOutputStream, DigestOutputStream, InflaterOutputStream, PrintStream

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected OutputStream

  out

  The underlying output stream to be filtered.

• Constructor Summary

  Constructors
  Constructor

  Description

  FilterOutputStream(OutputStream out)

  Creates an output stream filter built on top of the specified underlying output stream.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  close()

  Closes this output stream and releases any system resources associated with the stream.

  void

  flush()

  Flushes this output stream and forces any buffered output bytes to be written out to the stream.

  void

  write(byte[] b)

  Writes b.length bytes to this output stream.

  void

  write(byte[] b, int off, int len)

  Writes len bytes from the specified byte array starting at offset off to this output stream.

  void

  write(int b)

  Writes the specified byte to this output stream.

  Methods declared in class java.io.OutputStream

  nullOutputStream

  Methods declared in class java.lang.Object

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

• Field Details

  • out

    protected OutputStream out

    The underlying output stream to be filtered.

• Constructor Details

  • FilterOutputStream

    public FilterOutputStream(OutputStream out)

    Creates an output stream filter built on top of the specified underlying output stream.

    Parameters:

    out - the underlying output stream to be assigned to the field this.out for later use, or null if this instance is to be created without an underlying stream.

• Method Details

  • write

    public void write(int b) throws IOException

    Writes the specified byte to this output stream.

    The write method of FilterOutputStream calls the write method of its underlying output stream, that is, it performs out.write(b).

    Implements the abstract write method of OutputStream.

    Specified by:

    write in class OutputStream

    Parameters:

    b - the byte.

    Throws:

    IOException - if an I/O error occurs.

  • write

    public void write(byte[] b) throws IOException

    Writes b.length bytes to this output stream.

    Overrides:

    write in class OutputStream

    Implementation Requirements:

    The write method of FilterOutputStream calls its write method of three arguments with the arguments b, 0, and b.length.

    Implementation Note:

    Note that this method does not call the one-argument write method of its underlying output stream with the single argument b.

    Parameters:

    b - the data to be written.

    Throws:

    IOException - if an I/O error occurs.

    See Also:

    • write(byte[], int, int)

  • write

    public void write(byte[] b, int off, int len) throws IOException

    Writes len bytes from the specified byte array starting at offset off to this output stream.

    Overrides:

    write in class OutputStream

    Implementation Requirements:

    The write method of FilterOutputStream calls the write method of one argument on each byte to output.

    Implementation Note:

    Note that this method does not call the write method of its underlying output stream with the same arguments. Subclasses of FilterOutputStream should provide a more efficient implementation of this method.

    Parameters:

    b - the data.

    off - the start offset in the data.

    len - the number of bytes to write.

    Throws:

    IOException - if an I/O error occurs.

    IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off

    See Also:

    • write(int)

  • flush

    public void flush() throws IOException

    Flushes this output stream and forces any buffered output bytes to be written out to the stream.

    Specified by:

    flush in interface Flushable

    Overrides:

    flush in class OutputStream

    Implementation Requirements:

    The flush method of FilterOutputStream calls the flush method of its underlying output stream.

    Throws:

    IOException - if an I/O error occurs.

    See Also:

    • out

  • close

    public void close() throws IOException

    Closes this output stream and releases any system resources associated with the stream.

    Specified by:

    close in interface AutoCloseable

    Specified by:

    close in interface Closeable

    Overrides:

    close in class OutputStream

    Implementation Requirements:

    When not already closed, the close method of FilterOutputStream calls its flush method, and then calls the close method of its underlying output stream.

    Throws:

    IOException - if an I/O error occurs.

    See Also:

    • flush()
    • out

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