org.extex.dviware.type
Class AbstractDviCode

java.lang.Object
  org.extex.dviware.type.AbstractDviCode

All Implemented Interfaces:

DviCode

Direct Known Subclasses:

DviBop, DviDown, DviEop, DviFnt, DviFntDef, DviPop, DviPostamble, DviPreamble, DviPush, DviPutChar, DviPutRule, DviRight, DviSetChar, DviSetRule, DviW, DviW0, DviX, DviX0, DviXxx, DviY, DviY0, DviZ, DviZ0

public abstract class AbstractDviCode
extends java.lang.Object
implements DviCode

This is an abstract base class for DVI instructions.

Version:

$Revision: 5428 $

Author:

Gerd Neugebauer

Field Summary

protected static int	ONE_BYTE_MASK The constant ONE_BYTE_MASK contains the bit mask for a single byte.
protected static int	THREE_BYTE_MASK The constant THREE_BYTE_MASK contains the bit mask for a triple byte.
protected static int	TWO_BYTE_MASK The constant TWO_BYTE_MASK contains the bit mask for a double byte.

Fields inherited from interface org.extex.dviware.type.DviCode

POP, PUSH, W0, X0, Y0, Z0

Constructor Summary

protected

AbstractDviCode(java.lang.String name) Creates a new object.

Method Summary

java.lang.String	getName() Getter for name.
protected int	opcode(int baseOpcode, int value, java.io.OutputStream stream) Write an opcode and some unsigned value to the output stream.
protected int	opcodeSigned(int baseOpcode, int value, java.io.OutputStream stream) Write an opcode and some signed value to the output stream.
protected static java.lang.String	variant(int value) Determine which variant of a DVI instruction is needed for the operand.
protected static void	write2(java.io.OutputStream stream, int value) Write two bytes to the output stream.
protected void	write3(java.io.OutputStream stream, int value) Write three bytes to the output stream.
protected void	write4(java.io.OutputStream stream, int value) Write four bytes to the output stream.

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.extex.dviware.type.DviCode

write

Field Detail

ONE_BYTE_MASK

protected static final int ONE_BYTE_MASK

The constant ONE_BYTE_MASK contains the bit mask for a single byte.

See Also:

Constant Field Values

THREE_BYTE_MASK

protected static final int THREE_BYTE_MASK

The constant THREE_BYTE_MASK contains the bit mask for a triple byte.

See Also:

Constant Field Values

TWO_BYTE_MASK

protected static final int TWO_BYTE_MASK

The constant TWO_BYTE_MASK contains the bit mask for a double byte.

See Also:

Constant Field Values

Constructor Detail

AbstractDviCode

protected AbstractDviCode(java.lang.String name)

Creates a new object.

Parameters:

name - the name of the dvi instruction

Method Detail

variant

protected static java.lang.String variant(int value)

Determine which variant of a DVI instruction is needed for the operand.

Parameters:

value - the unsigned value

Returns:

the variant

write2

protected static void write2(java.io.OutputStream stream,
                             int value)
                      throws java.io.IOException

Write two bytes to the output stream.

Parameters:

stream - the output stream to write to

value - the value

Throws:

java.io.IOException - in case of an error

getName

public java.lang.String getName()

Getter for name.

Specified by:

getName in interface DviCode

Returns:

the name

opcode

protected int opcode(int baseOpcode,
                     int value,
                     java.io.OutputStream stream)
              throws java.io.IOException

Write an opcode and some unsigned value to the output stream. The value determines the exact opcode. If the value fits in one byte then the base opcode is used. If two bytes are needed then 1 is added. If two bytes are needed then 2 is added. Finally if all four bytes are needed then 3 is added to the base opcode.

Parameters:

baseOpcode - the opcode

value - the value

stream - the output stream to write to

Returns:

the number of bytes written

Throws:

java.io.IOException - in case of an error

opcodeSigned

protected int opcodeSigned(int baseOpcode,
                           int value,
                           java.io.OutputStream stream)
                    throws java.io.IOException

Write an opcode and some signed value to the output stream. The value determines the exact opcode. If the value fits in one byte then the base opcode is used. If two bytes are needed then 1 is added. If two bytes are needed then 2 is added. Finally if all four bytes are needed then 3 is added to the base opcode.

Parameters:

baseOpcode - the opcode

value - the value

stream - the output stream to write to

Returns:

the number of bytes written

Throws:

java.io.IOException - in case of an error

write3

protected void write3(java.io.OutputStream stream,
                      int value)
               throws java.io.IOException

Write three bytes to the output stream.

Parameters:

stream - the output stream to write to

value - the value

Throws:

java.io.IOException - in case of an error

write4

protected void write4(java.io.OutputStream stream,
                      int value)
               throws java.io.IOException

Write four bytes to the output stream.

Parameters:

stream - the output stream to write to

value - the value

Throws:

java.io.IOException - in case of an error