jpl.mipl.io.vicar
Class VicarDataInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          jpl.mipl.io.vicar.VicarDataInputStream

All Implemented Interfaces:

Closeable, DataInput

Direct Known Subclasses:

VicarSwapDataInputStream, VicarVaxDataInputStream

public class VicarDataInputStream
extends FilterInputStream
implements DataInput

VicarDataInputStream lets an application read primitive data types from an input stream; the data are converted (if necessary) from the int and real formats specified in the VicarDataFormat object that is passed in via the constructor.

Field Summary

protected long[]	_ieeeDouble
protected int[]	_ieeeFloat
protected int	_intFmtCode
protected long[]	_rawDouble
protected int[]	_rawFloat
protected int	_realFmtCode
protected long[]	_vaxDouble
protected int[]	_vaxFloat

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

VicarDataInputStream(InputStream in, int intFmtCode, int realFmtCode)
Creates a new VicarDataInputStream to read data from the specified input stream.

Method Summary

int	read(byte[] b) Reads up to byte.length bytes of data from this input stream into an array of bytes.
int	read(byte[] b, int off, int len) Reads up to len bytes of data from this input stream into an array of bytes.
boolean	readBoolean() Reads a boolean from this data input stream.
byte	readByte() Reads a signed 8-bit value from this data input stream.
char	readChar() Reads a Unicode character from this data input stream.
double	readDouble() Reads a double from this data input stream.
float	readFloat() Reads a float from this data input stream.
void	readFully(byte[] b) Reads b.length bytes from this data input stream into the byte array.
void	readFully(byte[] b, int off, int len) Reads exactly len bytes from this data input stream into the byte array.
int	readInt() Reads a signed 32-bit integer from this input stream.
String	readLine() Deprecated. This method does not properly convert bytes to characters. As of JDK 1.1, the preferred way to read lines of text is via the BufferedReader.readLine() method. Programs that use the DataInputStream class to read lines can be converted to use the BufferedReader class by replacing code of the form DataInputStream d = new DataInputStream(in); with BufferedReader d = new BufferedReader(new InputStreamReader(in));
long	readLong() Reads a signed 64-bit integer from this data input stream.
short	readShort() Reads a signed 16-bit number from this data input stream.
int	readUnsignedByte() Reads an unsigned 8-bit number from this data input stream.
int	readUnsignedShort() Reads an unsigned 16-bit number from this data input stream.
String	readUTF() Reads in a string that has been encoded using a modified UTF-8 format from this data input stream.
static String	readUTF(DataInput in) Reads in a string from the specified data input stream.
protected long[]	shift_right_3(long[] y, long[] x)
protected int[]	shift_right(int[] x)
int	skipBytes(int n) Skips exactly n bytes of input in the underlying input stream.

Methods inherited from class java.io.FilterInputStream

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

Methods inherited from class java.lang.Object

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

Field Detail

_intFmtCode

protected int _intFmtCode

_realFmtCode

protected int _realFmtCode

_rawFloat

protected int[] _rawFloat

_vaxFloat

protected int[] _vaxFloat

_ieeeFloat

protected int[] _ieeeFloat

_rawDouble

protected long[] _rawDouble

_vaxDouble

protected long[] _vaxDouble

_ieeeDouble

protected long[] _ieeeDouble

Constructor Detail

VicarDataInputStream

public VicarDataInputStream(InputStream in,
                            int intFmtCode,
                            int realFmtCode)

Creates a new VicarDataInputStream to read data from the specified input stream.

Parameters:

in - the input stream you`re wrapping

format - the data format to convert *from*

Method Detail

readShort

public short readShort()
                throws IOException

Reads a signed 16-bit number from this data input stream. The method reads two bytes from the underlying input stream.

This method blocks until the two bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readShort in interface DataInput

Returns:

the next two bytes of this input stream, interpreted as a signed 16-bit number.

Throws:

EOFException - if this input stream reaches the end before reading two bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readUnsignedShort

public int readUnsignedShort()
                      throws IOException

Reads an unsigned 16-bit number from this data input stream. This method reads two bytes from the underlying input stream.

This method blocks until the two bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readUnsignedShort in interface DataInput

Returns:

the next two bytes of this input stream, interpreted as an unsigned 16-bit integer.

Throws:

EOFException - if this input stream reaches the end before reading two bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readInt

public int readInt()
            throws IOException

Reads a signed 32-bit integer from this input stream. This method reads four bytes from the underlying input stream.

This method blocks until the four bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readInt in interface DataInput

Returns:

the next four bytes of this input stream, interpreted as an int.

Throws:

EOFException - if this input stream reaches the end before reading four bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readLong

public long readLong()
              throws IOException

Reads a signed 64-bit integer from this data input stream. This method reads eight bytes from the underlying input stream.

This method blocks until the eight bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readLong in interface DataInput

Returns:

the next eight bytes of this input stream, interpreted as a long.

Throws:

EOFException - if this input stream reaches the end before reading eight bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readFloat

public float readFloat()
                throws IOException

Reads a float from this data input stream. This method reads an int value as if by the readInt method and then converts that int to a float using the intBitsToFloat method in class Float. This method blocks until the four bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readFloat in interface DataInput

Returns:

the next four bytes of this input stream, interpreted as a float.

Throws:

EOFException - if this input stream reaches the end before reading four bytes.

IOException - if an I/O error occurs.

See Also:

DataInputStream.readInt(), Float.intBitsToFloat(int)

shift_right

protected int[] shift_right(int[] x)

shift_right_3

protected long[] shift_right_3(long[] y,
                               long[] x)

readDouble

public double readDouble()
                  throws IOException

Reads a double from this data input stream. This method reads a long value as if by the readLong method and then converts that long to a double using the longBitsToDouble method in class Double.

This method blocks until the eight bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readDouble in interface DataInput

Returns:

the next eight bytes of this input stream, interpreted as a double.

Throws:

EOFException - if this input stream reaches the end before reading eight bytes.

IOException - if an I/O error occurs.

See Also:

DataInputStream.readLong(), Double.longBitsToDouble(long)

read

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

Reads up to byte.length bytes of data from this input stream into an array of bytes. This method blocks until some input is available.

The read method of DataInputStream calls the read method of its underlying input stream with the three arguments b, 0, and b.length and returns whatever value that method returns.

Overrides:

read in class FilterInputStream

Parameters:

b - the buffer into which the data is read.

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws:

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in, InputStream.read(byte[], int, int)

read

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

Reads up to len bytes of data from this input stream into an array of bytes. This method blocks until some input is available.

The read method of DataInputStream calls the read method of its underlying input stream with the same arguments and returns whatever value that method returns.

Overrides:

read in class FilterInputStream

Parameters:

b - the buffer into which the data is read.

off - the start offset of the data.

len - the maximum number of bytes read.

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws:

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in, InputStream.read(byte[], int, int)

readFully

public final void readFully(byte[] b)
                     throws IOException

Reads b.length bytes from this data input stream into the byte array. This method reads repeatedly from the underlying stream until all the bytes are read. This method blocks until all the bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readFully in interface DataInput

Parameters:

b - the buffer into which the data is read.

Throws:

EOFException - if this input stream reaches the end before reading all the bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readFully

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

Reads exactly len bytes from this data input stream into the byte array. This method reads repeatedly from the underlying stream until all the bytes are read. This method blocks until all the bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readFully in interface DataInput

Parameters:

b - the buffer into which the data is read.

off - the start offset of the data.

len - the number of bytes to read.

Throws:

EOFException - if this input stream reaches the end before reading all the bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

skipBytes

public final int skipBytes(int n)
                    throws IOException

Skips exactly n bytes of input in the underlying input stream. This method blocks until all the bytes are skipped, the end of the stream is detected, or an exception is thrown.

Specified by:

skipBytes in interface DataInput

Parameters:

n - the number of bytes to be skipped.

Returns:

the number of bytes skipped, which is always n.

Throws:

EOFException - if this input stream reaches the end before skipping all the bytes.

IOException - if an I/O error occurs.

readBoolean

public final boolean readBoolean()
                          throws IOException

Reads a boolean from this data input stream. This method reads a single byte from the underlying input stream. A value of 0 represents false. Any other value represents true. This method blocks until either the byte is read, the end of the stream is detected, or an exception is thrown.

Specified by:

readBoolean in interface DataInput

Returns:

the boolean value read.

Throws:

EOFException - if this input stream has reached the end.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readByte

public final byte readByte()
                    throws IOException

Reads a signed 8-bit value from this data input stream. This method reads a byte from the underlying input stream. If the byte read is b, where 0 <= b <= 255, then the result is:

(byte)(b)

This method blocks until either the byte is read, the end of the stream is detected, or an exception is thrown.

Specified by:

readByte in interface DataInput

Returns:

the next byte of this input stream as a signed 8-bit byte.

Throws:

EOFException - if this input stream has reached the end.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readUnsignedByte

public final int readUnsignedByte()
                           throws IOException

Reads an unsigned 8-bit number from this data input stream. This method reads a byte from this data input stream's underlying input stream and returns that byte. This method blocks until the byte is read, the end of the stream is detected, or an exception is thrown.

Specified by:

readUnsignedByte in interface DataInput

Returns:

the next byte of this input stream, interpreted as an unsigned 8-bit number.

Throws:

EOFException - if this input stream has reached the end.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readChar

public final char readChar()
                    throws IOException

Reads a Unicode character from this data input stream. This method reads two bytes from the underlying input stream. If the bytes read, in order, are b1 and b2, where 0 <= b1, b1 <= 255, then the result is equal to:

(char)((b1 << 8) | b2)

This method blocks until either the two bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readChar in interface DataInput

Returns:

the next two bytes of this input stream as a Unicode character.

Throws:

EOFException - if this input stream reaches the end before reading two bytes.

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

readLine

public final String readLine()
                      throws IOException

Deprecated. This method does not properly convert bytes to characters. As of JDK 1.1, the preferred way to read lines of text is via the BufferedReader.readLine() method. Programs that use the DataInputStream class to read lines can be converted to use the BufferedReader class by replacing code of the form

DataInputStream d = new DataInputStream(in);

with

BufferedReader d = new BufferedReader(new InputStreamReader(in));

Reads the next line of text from this data input stream. This method successively reads bytes from the underlying input stream until it reaches the end of a line of text.

A line of text is terminated by a carriage return character ('\r'), a newline character ('\n'), a carriage return character immediately followed by a newline character, or the end of the input stream. The line-terminating character(s), if any, are not returned as part of the string that is returned.

This method blocks until a newline character is read, a carriage return and the byte following it are read (to see if it is a newline), the end of the stream is detected, or an exception is thrown.

Specified by:

readLine in interface DataInput

Returns:

the next line of text from this input stream, or null if no bytes are read before end-of-file is reached.

Throws:

IOException - if an I/O error occurs.

See Also:

BufferedReader.readLine(), FilterInputStream.in

readUTF

public final String readUTF()
                     throws IOException

Reads in a string that has been encoded using a modified UTF-8 format from this data input stream. This method calls readUTF(this). See readUTF(java.io.DataInput) for a more complete description of the format.

This method blocks until all the bytes are read, the end of the stream is detected, or an exception is thrown.

Specified by:

readUTF in interface DataInput

Returns:

a Unicode string.

Throws:

EOFException - if this input stream reaches the end before reading all the bytes.

IOException - if an I/O error occurs.

See Also:

DataInputStream.readUTF(java.io.DataInput)

readUTF

public static final String readUTF(DataInput in)
                            throws IOException

Reads in a string from the specified data input stream. The string has been encoded using a modified UTF-8 format.

The first two bytes are read as if by readUnsignedShort. This value gives the number of following bytes that are in the encoded string, not the length of the resulting string. The following bytes are then interpreted as bytes encoding characters in the UTF-8 format and are converted into characters.

This method blocks until all the bytes are read, the end of the stream is detected, or an exception is thrown.

Parameters:

in - a data input stream.

Returns:

a Unicode string.

Throws:

EOFException - if the input stream reaches the end before all the bytes.

IOException - if an I/O error occurs.

UTFDataFormatException - if the bytes do not represent a valid UTF-8 encoding of a Unicode string.

See Also:

DataInputStream.readUnsignedShort()