Package org.firebirdsql.gds.impl.wire

## Class XdrInputStream

- java.lang.Object
- - java.io.InputStream
  - - java.io.FilterInputStream
    - - org.firebirdsql.gds.impl.wire.XdrInputStream

- All Implemented Interfaces:
    `java.io.Closeable`, `java.lang.AutoCloseable`

      public final class XdrInputStream
      extends java.io.FilterInputStream

  `XdrInputStream` is an input stream for reading in data that is in the XDR format. An `XdrInputStream` instance is wrapped around an underlying `java.io.InputStream`.

  This class is not thread-safe.

  Version:
    1.0
  Author:
    Alejandro Alberola, David Jencks, Mark Rotteveel

- - ### Field Summary

    - ### Fields inherited from class java.io.FilterInputStream

      `in`

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `XdrInputStream​(java.io.InputStream in)` | Create a new instance of `XdrInputStream`.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `void` | `enableDecompression()` | Wraps the underlying stream for zlib decompression.
    `byte[]` | `readBuffer()` | Read in a byte buffer.
    `void` | `readFully​(byte[] b, int off, int len)` | Read a given amount of data from the underlying input stream.
    `int` | `readInt()` | Read in an `int`.
    `long` | `readLong()` | Read in a `long`.
    `byte[]` | `readRawBuffer​(int len)` | Read in a raw array of bytes.
    `int` | `readShort()` | Read in a `short`.
    `java.lang.String` | `readString​(Encoding encoding)` | Read in a `String`.
    `void` | `setCipher​(javax.crypto.Cipher cipher)` |
    `int` | `skipFully​(int numbytes)` | Skips the specified number of bytes.
    `int` | `skipPadding​(int length)` | Skips the padding after a buffer of the specified length.

    - ### Methods inherited from class java.io.FilterInputStream

      `available, close, mark, markSupported, read, read, read, reset, skip`

    - ### Methods inherited from class java.io.InputStream

      `nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo`

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

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

- - ### Constructor Detail

    - #### XdrInputStream

          public XdrInputStream​(java.io.InputStream in)

      Create a new instance of `XdrInputStream`.
      Parameters:
        `in` - The underlying `InputStream` to read from

  - ### Method Detail

    - #### skipPadding

          public int skipPadding​(int length)
                          throws java.io.IOException

      Skips the padding after a buffer of the specified length. The number of bytes to skip is calculated as `(4 - length) & 3`.
      Parameters:
        `length` - Length of the previously read buffer
      Returns:
        Actual number of bytes skipped
      Throws:
        `java.io.IOException` - IOException if an error occurs while reading from the underlying input stream
      See Also:
        `XdrOutputStream.writePadding(int, int)`

    - #### skipFully

          public int skipFully​(int numbytes)
                        throws java.io.IOException

      Skips the specified number of bytes.
      Parameters:
        `numbytes` - Number of bytes to skip.
      Returns:
        Actual number of bytes skipped (usually `numbytes`, unless the underlying input stream is closed).
      Throws:
        `java.io.IOException` - IOException if an error occurs while reading from the underlying input stream

    - #### readBuffer

          public byte[] readBuffer()
                            throws java.io.IOException

      Read in a byte buffer.
      Returns:
        The buffer that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readRawBuffer

          public byte[] readRawBuffer​(int len)
                               throws java.io.IOException

      Read in a raw array of bytes.
      Parameters:
        `len` - The number of bytes to read
      Returns:
        The byte buffer that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readString

          public java.lang.String readString​(Encoding encoding)
                                      throws java.io.IOException

      Read in a `String`.
      Returns:
        The `String` that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readLong

          public long readLong()
                        throws java.io.IOException

      Read in a `long`.
      Returns:
        The `long` that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readInt

          public int readInt()
                      throws java.io.IOException

      Read in an `int`.
      Returns:
        The `int` that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readShort

          public int readShort()
                        throws java.io.IOException

      Read in a `short`.
      Returns:
        The `short` that was read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### readFully

          public void readFully​(byte[] b,
                                int off,
                                int len)
                         throws java.io.IOException

      Read a given amount of data from the underlying input stream. The data that is read is stored in `b`, starting from offset `off`.
      Parameters:
        `b` - The byte buffer to hold the data that is read
        `off` - The offset at which to start storing data in `b`
        `len` - The number of bytes to be read
      Throws:
        `java.io.IOException` - if an error occurs while reading from the underlying input stream

    - #### enableDecompression

          @InternalApi
          public void enableDecompression()
                                   throws java.io.IOException

      Wraps the underlying stream for zlib decompression.
      Throws:
        `java.io.IOException` - If the underlying stream is already set up for decompression

    - #### setCipher

          public void setCipher​(javax.crypto.Cipher cipher)
                         throws java.io.IOException

      Throws:
        `java.io.IOException`