Top Description Fields Constructors Methods
org.jboss.marshalling

public Class SimpleDataInput

extends ByteInputStream
implements DataInput
Class Inheritance
All Implemented Interfaces
java.io.DataInput
Known Direct Subclasses
org.jboss.marshalling.AbstractObjectInput
Imports
java.io.DataInput, .EOFException, .IOException
A simple base implementation of DataInput which wraps a ByteInput. This implementation maintains an internal buffer.

Field Summary

Modifier and TypeField and Description
protected final byte[]
buffer

The internal buffer.

protected int
limit

The buffer limit.

protected int
position

The buffer position.

Inherited from org.jboss.marshalling.ByteInputStream:
byteInput

Constructor Summary

AccessConstructor and Description
public
SimpleDataInput(int
the internal buffer size to use
bufferSize)

Construct a new instance which wraps nothing.

public
SimpleDataInput(int
the internal buffer size to use
bufferSize, ByteInput
the byte input to initially wrap
byteInput)

Construct a new instance.

public
SimpleDataInput(final ByteInput
the byte input to initially wrap
byteInput)

Construct a new instance.

Method Summary

Modifier and TypeMethod and Description
public int
available()

Overrides org.jboss.marshalling.ByteInputStream.available.

Implements org.jboss.marshalling.ByteInput.available.

Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream.
public void
close()

Overrides org.jboss.marshalling.ByteInputStream.close.

Implements java.io.Closeable.close.

Closes this stream and releases any system resources associated with it.
private static EOFException
eofOnRead()

protected void
finish()

Finish reading from the current input.

public int
read()

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Reads the next byte of data from the input stream.
public int
read(final byte[]
the destination array
b)

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Read some bytes from the input stream into the given array.
public int
read(final byte[]
the destination array
b, final int
the offset into the array into which data should be read
off, final int
the number of bytes to attempt to fill in the destination array
len)

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Read some bytes from the input stream into the given array.
public boolean
readBoolean()

Implements java.io.DataInput.readBoolean.

Reads one input byte and returns true if that byte is nonzero, false if that byte is zero.
public byte
readByte()

Implements java.io.DataInput.readByte.

Reads and returns one input byte.
public char
readChar()

Implements java.io.DataInput.readChar.

Reads two input bytes and returns a char value.
public double
readDouble()

Implements java.io.DataInput.readDouble.

Reads eight input bytes and returns a double value.
public float
readFloat()

Implements java.io.DataInput.readFloat.

Reads four input bytes and returns a float value.
public void
readFully(final byte[]
the buffer into which the data is read.
b)

Implements java.io.DataInput.readFully.

Reads some bytes from an input stream and stores them into the buffer array b.
public void
readFully(final byte[]
the buffer into which the data is read.
b, int
an int specifying the offset in the data array b.
off, int
an int specifying the number of bytes to read.
len)

Implements java.io.DataInput.readFully.

Reads len bytes from an input stream.
public int
readInt()

Implements java.io.DataInput.readInt.

Reads four input bytes and returns an int value.
protected int

Returns:

the value
readIntDirect()

Read an int value.

public String
readLine()

Implements java.io.DataInput.readLine.

Reads the next line of text from the input stream.
public long
readLong()

Implements java.io.DataInput.readLong.

Reads eight input bytes and returns a long value.
protected long
readLongDirect()

public short
readShort()

Implements java.io.DataInput.readShort.

Reads two input bytes and returns a short value.
public int
readUnsignedByte()

Implements java.io.DataInput.readUnsignedByte.

Reads one input byte, zero-extends it to type int, and returns the result, which is therefore in the range 0 through 255.
protected int

Returns:

the unsigned byte
readUnsignedByteDirect()

Read an unsigned byte directly.

public int
readUnsignedShort()

Implements java.io.DataInput.readUnsignedShort.

Reads two input bytes and returns an int value in the range 0 through 65535.
public String
readUTF()

Implements java.io.DataInput.readUTF.

Reads in a string that has been encoded using a modified UTF-8 format.
public long
skip(final long
the number of bytes to attempt to skip
n)

Overrides org.jboss.marshalling.ByteInputStream.skip.

Implements org.jboss.marshalling.ByteInput.skip.

Skips over and discards up to n bytes of data from this input stream.
public int
skipBytes(final int
the number of bytes to be skipped.
n)

Implements java.io.DataInput.skipBytes.

Makes an attempt to skip over n bytes of data from the input stream, discarding the skipped bytes.
protected void
start(final ByteInput
the new input from which to read
byteInput)

Start reading from the given input.

Field Detail

bufferback to summary
protected final byte[] buffer

The internal buffer.

limitback to summary
protected int limit

The buffer limit.

positionback to summary
protected int position

The buffer position.

Constructor Detail

SimpleDataInputback to summary
public SimpleDataInput(int bufferSize)

Construct a new instance which wraps nothing.

Parameters
bufferSize:int

the internal buffer size to use

SimpleDataInputback to summary
public SimpleDataInput(int bufferSize, ByteInput byteInput)

Construct a new instance.

Parameters
bufferSize:int

the internal buffer size to use

byteInput:ByteInput

the byte input to initially wrap

SimpleDataInputback to summary
public SimpleDataInput(final ByteInput byteInput)

Construct a new instance. A default buffer size is used.

Parameters
byteInput:ByteInput

the byte input to initially wrap

Method Detail

availableback to summary
public int available() throws IOException

Overrides org.jboss.marshalling.ByteInputStream.available.

Implements org.jboss.marshalling.ByteInput.available.

Doc from org.jboss.marshalling.ByteInputStream.available.

Returns an estimate of the number of bytes that can be read (or skipped over) from this input stream without blocking by the next invocation of a method for this input stream.

Returns:int

Doc from org.jboss.marshalling.ByteInput.available.

the number of bytes

Exceptions
IOException:

Doc from org.jboss.marshalling.ByteInput.available.

if an error occurs

closeback to summary
public void close() throws IOException

Overrides org.jboss.marshalling.ByteInputStream.close.

Implements java.io.Closeable.close.

Doc from org.jboss.marshalling.ByteInputStream.close.

Closes this stream and releases any system resources associated with it. If the stream is already closed then invoking this method has no effect.

As noted in AutoCloseable#close(), cases where the close may fail require careful attention. It is strongly advised to relinquish the underlying resources and to internally mark the Closeable as closed, prior to throwing the IOException.

Exceptions
IOException:

Doc from java.io.Closeable.close.

if an I/O error occurs

eofOnReadback to summary
private static EOFException eofOnRead()
finishback to summary
protected void finish() throws IOException

Finish reading from the current input. The internal buffer is discarded, not flushed.

Exceptions
IOException:
not thrown by this implementation, but may be overridden to be thrown if a problem occurs
readback to summary
public int read() throws IOException

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Doc from org.jboss.marshalling.ByteInputStream.read.

Reads the next byte of data from the input stream. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

Returns:int

Doc from org.jboss.marshalling.ByteInput.read.

the next byte, or -1 if the end of stream has been reached

Exceptions
IOException:

Doc from org.jboss.marshalling.ByteInput.read.

if an error occurs

readback to summary
public int read(final byte[] b) throws IOException

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Doc from org.jboss.marshalling.ByteInputStream.read.

Read some bytes from the input stream into the given array. Returns the number of bytes actually read (possibly zero), or -1 if the end of stream has been reached.

Parameters
b:byte[]

Doc from org.jboss.marshalling.ByteInput.read.

the destination array

Returns:int

Doc from org.jboss.marshalling.ByteInput.read.

the number of bytes read (possibly zero), or -1 if the end of stream has been reached

Exceptions
IOException:

Doc from org.jboss.marshalling.ByteInput.read.

if an error occurs

readback to summary
public int read(final byte[] b, final int off, final int len) throws IOException

Overrides org.jboss.marshalling.ByteInputStream.read.

Implements org.jboss.marshalling.ByteInput.read.

Doc from org.jboss.marshalling.ByteInputStream.read.

Read some bytes from the input stream into the given array. Returns the number of bytes actually read (possibly zero), or -1 if the end of stream has been reached.

Parameters
b:byte[]

Doc from org.jboss.marshalling.ByteInput.read.

the destination array

off:int

Doc from org.jboss.marshalling.ByteInput.read.

the offset into the array into which data should be read

len:int

Doc from org.jboss.marshalling.ByteInput.read.

the number of bytes to attempt to fill in the destination array

Returns:int

Doc from org.jboss.marshalling.ByteInput.read.

the number of bytes read (possibly zero), or -1 if the end of stream has been reached

Exceptions
IOException:

Doc from org.jboss.marshalling.ByteInput.read.

if an error occurs

readBooleanback to summary
public boolean readBoolean() throws IOException

Implements java.io.DataInput.readBoolean.

Doc from java.io.DataInput.readBoolean.

Reads one input byte and returns true if that byte is nonzero, false if that byte is zero. This method is suitable for reading the byte written by the writeBoolean method of interface DataOutput.

Returns:boolean

the boolean value read.

Exceptions
IOException:
if an I/O error occurs.
readByteback to summary
public byte readByte() throws IOException

Implements java.io.DataInput.readByte.

Doc from java.io.DataInput.readByte.

Reads and returns one input byte. The byte is treated as a signed value in the range -128 through 127, inclusive. This method is suitable for reading the byte written by the writeByte method of interface DataOutput.

Returns:byte

the 8-bit value read.

Exceptions
IOException:
if an I/O error occurs.
readCharback to summary
public char readChar() throws IOException

Implements java.io.DataInput.readChar.

Doc from java.io.DataInput.readChar.

Reads two input bytes and returns a char value. Let a be the first byte read and b be the second byte. The value returned is: 

(char)((a << 8) | (b & 0xff))
This method is suitable for reading bytes written by the writeChar method of interface DataOutput.
Returns:char

the char value read.

Exceptions
IOException:
if an I/O error occurs.
readDoubleback to summary
public double readDouble() throws IOException

Implements java.io.DataInput.readDouble.

Doc from java.io.DataInput.readDouble.

Reads eight input bytes and returns a double value. It does this by first constructing a long value in exactly the manner of the readLong method, then converting this long value to a double in exactly the manner of the method Double.longBitsToDouble. This method is suitable for reading bytes written by the writeDouble method of interface DataOutput.

Returns:double

the double value read.

Exceptions
IOException:
if an I/O error occurs.
readFloatback to summary
public float readFloat() throws IOException

Implements java.io.DataInput.readFloat.

Doc from java.io.DataInput.readFloat.

Reads four input bytes and returns a float value. It does this by first constructing an int value in exactly the manner of the readInt method, then converting this int value to a float in exactly the manner of the method Float.intBitsToFloat. This method is suitable for reading bytes written by the writeFloat method of interface DataOutput.

Returns:float

the float value read.

Exceptions
IOException:
if an I/O error occurs.
readFullyback to summary
public void readFully(final byte[] b) throws IOException

Implements java.io.DataInput.readFully.

Doc from java.io.DataInput.readFully.

Reads some bytes from an input stream and stores them into the buffer array b. The number of bytes read is equal to the length of b.

This method blocks until one of the following conditions occurs:

  • b.length bytes of input data are available, in which case a normal return is made.
  • End of file is detected, in which case an EOFException is thrown.
  • An I/O error occurs, in which case an IOException other than EOFException is thrown.

If b is null, a NullPointerException is thrown. If b.length is zero, then no bytes are read. Otherwise, the first byte read is stored into element b[0], the next one into b[1], and so on. If an exception is thrown from this method, then it may be that some but not all bytes of b have been updated with data from the input stream.

Parameters
b:byte[]

the buffer into which the data is read.

Exceptions
IOException:
if an I/O error occurs.
readFullyback to summary
public void readFully(final byte[] b, int off, int len) throws IOException

Implements java.io.DataInput.readFully.

Doc from java.io.DataInput.readFully.

Reads len bytes from an input stream.

This method blocks until one of the following conditions occurs:

  • len bytes of input data are available, in which case a normal return is made.
  • End of file is detected, in which case an EOFException is thrown.
  • An I/O error occurs, in which case an IOException other than EOFException is thrown.

If b is null, a NullPointerException is thrown. If off is negative, or len is negative, or off+len is greater than the length of the array b, then an IndexOutOfBoundsException is thrown. If len is zero, then no bytes are read. Otherwise, the first byte read is stored into element b[off], the next one into b[off+1], and so on. The number of bytes read is, at most, equal to len.

Parameters
b:byte[]

the buffer into which the data is read.

off:int

an int specifying the offset in the data array b.

len:int

an int specifying the number of bytes to read.

Exceptions
IOException:
if an I/O error occurs.
readIntback to summary
public int readInt() throws IOException

Implements java.io.DataInput.readInt.

Doc from java.io.DataInput.readInt.

Reads four input bytes and returns an int value. Let a-d be the first through fourth bytes read. The value returned is: 

(((a & 0xff) << 24) | ((b & 0xff) << 16) |
 ((c & 0xff) <<  8) | (d & 0xff))
This method is suitable for reading bytes written by the writeInt method of interface DataOutput.
Returns:int

the int value read.

Exceptions
IOException:
if an I/O error occurs.
readIntDirectback to summary
protected int readIntDirect() throws IOException

Read an int value.

Returns:int

the value

Exceptions
IOException:
if an error occurs
readLineback to summary
public String readLine() throws IOException

Implements java.io.DataInput.readLine.

Doc from java.io.DataInput.readLine.

Reads the next line of text from the input stream. It reads successive bytes, converting each byte separately into a character, until it encounters a line terminator or end of file; the characters read are then returned as a String. Note that because this method processes bytes, it does not support input of the full Unicode character set.

If end of file is encountered before even one byte can be read, then null is returned. Otherwise, each byte that is read is converted to type char by zero-extension. If the character '\n' is encountered, it is discarded and reading ceases. If the character '\r' is encountered, it is discarded and, if the following byte converts to the character '\n', then that is discarded also; reading then ceases. If end of file is encountered before either of the characters '\n' and '\r' is encountered, reading ceases. Once reading has ceased, a String is returned that contains all the characters read and not discarded, taken in order. Note that every character in this string will have a value less than \u0100, that is, (char)256.

Returns:String

the next line of text from the input stream, or null if the end of file is encountered before a byte can be read.

Exceptions
IOException:
if an I/O error occurs.
readLongback to summary
public long readLong() throws IOException

Implements java.io.DataInput.readLong.

Doc from java.io.DataInput.readLong.

Reads eight input bytes and returns a long value. Let a-h be the first through eighth bytes read. The value returned is: 

(((long)(a & 0xff) << 56) |
 ((long)(b & 0xff) << 48) |
 ((long)(c & 0xff) << 40) |
 ((long)(d & 0xff) << 32) |
 ((long)(e & 0xff) << 24) |
 ((long)(f & 0xff) << 16) |
 ((long)(g & 0xff) <<  8) |
 ((long)(h & 0xff)))

This method is suitable for reading bytes written by the writeLong method of interface DataOutput.

Returns:long

the long value read.

Exceptions
IOException:
if an I/O error occurs.
readLongDirectback to summary
protected long readLongDirect() throws IOException
readShortback to summary
public short readShort() throws IOException

Implements java.io.DataInput.readShort.

Doc from java.io.DataInput.readShort.

Reads two input bytes and returns a short value. Let a be the first byte read and b be the second byte. The value returned is: 

(short)((a << 8) | (b & 0xff))
This method is suitable for reading the bytes written by the writeShort method of interface DataOutput.
Returns:short

the 16-bit value read.

Exceptions
IOException:
if an I/O error occurs.
readUnsignedByteback to summary
public int readUnsignedByte() throws IOException

Implements java.io.DataInput.readUnsignedByte.

Doc from java.io.DataInput.readUnsignedByte.

Reads one input byte, zero-extends it to type int, and returns the result, which is therefore in the range 0 through 255. This method is suitable for reading the byte written by the writeByte method of interface DataOutput if the argument to writeByte was intended to be a value in the range 0 through 255.

Returns:int

the unsigned 8-bit value read.

Exceptions
IOException:
if an I/O error occurs.
readUnsignedByteDirectback to summary
protected int readUnsignedByteDirect() throws IOException

Read an unsigned byte directly.

Returns:int

the unsigned byte

Exceptions
IOException:
if an error occurs
readUnsignedShortback to summary
public int readUnsignedShort() throws IOException

Implements java.io.DataInput.readUnsignedShort.

Doc from java.io.DataInput.readUnsignedShort.

Reads two input bytes and returns an int value in the range 0 through 65535. Let a be the first byte read and b be the second byte. The value returned is: 

(((a & 0xff) << 8) | (b & 0xff))
This method is suitable for reading the bytes written by the writeShort method of interface DataOutput if the argument to writeShort was intended to be a value in the range 0 through 65535.
Returns:int

the unsigned 16-bit value read.

Exceptions
IOException:
if an I/O error occurs.
readUTFback to summary
public String readUTF() throws IOException

Implements java.io.DataInput.readUTF.

Doc from java.io.DataInput.readUTF.

Reads in a string that has been encoded using a modified UTF-8 format. The general contract of readUTF is that it reads a representation of a Unicode character string encoded in modified UTF-8 format; this string of characters is then returned as a String.

First, two bytes are read and used to construct an unsigned 16-bit integer in exactly the manner of the readUnsignedShort method . This integer value is called the UTF length and specifies the number of additional bytes to be read. These bytes are then converted to characters by considering them in groups. The length of each group is computed from the value of the first byte of the group. The byte following a group, if any, is the first byte of the next group.

If the first byte of a group matches the bit pattern 0xxxxxxx (where x means "may be 0 or 1"), then the group consists of just that byte. The byte is zero-extended to form a character.

If the first byte of a group matches the bit pattern 110xxxxx, then the group consists of that byte a and a second byte b. If there is no byte b (because byte a was the last of the bytes to be read), or if byte b does not match the bit pattern 10xxxxxx, then a UTFDataFormatException is thrown. Otherwise, the group is converted to the character: 

(char)(((a & 0x1F) << 6) | (b & 0x3F))
If the first byte of a group matches the bit pattern 1110xxxx, then the group consists of that byte a and two more bytes b and c. If there is no byte c (because byte a was one of the last two of the bytes to be read), or either byte b or byte c does not match the bit pattern 10xxxxxx, then a UTFDataFormatException is thrown. Otherwise, the group is converted to the character: 
(char)(((a & 0x0F) << 12) | ((b & 0x3F) << 6) | (c & 0x3F))
If the first byte of a group matches the pattern 1111xxxx or the pattern 10xxxxxx, then a UTFDataFormatException is thrown.

If end of file is encountered at any time during this entire process, then an EOFException is thrown.

After every group has been converted to a character by this process, the characters are gathered, in the same order in which their corresponding groups were read from the input stream, to form a String, which is returned.

The writeUTF method of interface DataOutput may be used to write data that is suitable for reading by this method.

Returns:String

a Unicode string.

Exceptions
IOException:
if an I/O error occurs.
skipback to summary
public long skip(final long n) throws IOException

Overrides org.jboss.marshalling.ByteInputStream.skip.

Implements org.jboss.marshalling.ByteInput.skip.

Doc from org.jboss.marshalling.ByteInputStream.skip.

Skips over and discards up to n bytes of data from this input stream. If the end of stream is reached, this method returns 0 in order to be consistent with java.io.InputStream#skip(long).

Parameters
n:long

Doc from org.jboss.marshalling.ByteInput.skip.

the number of bytes to attempt to skip

Returns:long

Doc from org.jboss.marshalling.ByteInput.skip.

the number of bytes skipped

Exceptions
IOException:

Doc from org.jboss.marshalling.ByteInput.skip.

if an error occurs

skipBytesback to summary
public int skipBytes(final int n) throws IOException

Implements java.io.DataInput.skipBytes.

Doc from java.io.DataInput.skipBytes.

Makes an attempt to skip over n bytes of data from the input stream, discarding the skipped bytes. However, it may skip over some smaller number of bytes, possibly zero. This may result from any of a number of conditions; reaching end of file before n bytes have been skipped is only one possibility. This method never throws an EOFException. The actual number of bytes skipped is returned.

Parameters
n:int

the number of bytes to be skipped.

Returns:int

the number of bytes actually skipped.

Exceptions
IOException:
if an I/O error occurs.
startback to summary
protected void start(final ByteInput byteInput) throws IOException

Start reading from the given input. The internal buffer is discarded.

Parameters
byteInput:ByteInput

the new input from which to read

Exceptions
IOException:
not thrown by this implementation, but may be overridden to be thrown if a problem occurs