Package com.sun.pdfview.function

Class FunctionType4

java.lang.Object

com.sun.pdfview.function.PDFFunction

com.sun.pdfview.function.FunctionType4

public class FunctionType4
extends PDFFunction

A PostScript function is represented as a stream containing code written in a small subset of the PostScript language. This reference is taken from the (3200-1:2008:7.10.5)

http://www.adobe.com/devnet/acrobat/pdfs/adobe_supplement_iso32000.pdf

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) class	FunctionType4.Expression
(package private) class	FunctionType4.Operation

Field Summary

Fields

Modifier and Type	Field	Description
private static HashSet<FunctionType4.Operation>	operationSet	the set of all Operations we support.
private LinkedList<Object>	stack	the stack of operations.
private LinkedList	tokens	the list of tokens and sub-expressions.

Fields inherited from class com.sun.pdfview.function.PDFFunction

TYPE_0, TYPE_2, TYPE_3, TYPE_4

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	FunctionType4()	Creates a new instance of FunctionType4

Method Summary

Modifier and Type	Method	Description
protected void	doFunction(float[] inputs, int inputOffset, float[] outputs, int outputOffset)	Map from m input values to n output values.
private void	initOperations()	Initialize the operations that we can perform.
protected void	parse(PDFObject obj)	Read the function information from a PDF Object
private boolean	popBoolean()
private double	popDouble()
private FunctionType4.Expression	popExpression()
private long	popLong()
private Object	popObject()
private void	pushBoolean(boolean arg)
private void	pushDouble(double arg)
private void	pushExpression(FunctionType4.Expression expresson)
private void	pushLong(long arg)
private void	pushObject(Object obj)
private void	readPS(ByteBuffer buf)	parse the postscript operators and aguments from the stream.

Methods inherited from class com.sun.pdfview.function.PDFFunction

calculate, calculate, getDomain, getFunction, getNumInputs, getNumOutputs, getRange, getType, setDomain, setRange

Methods inherited from class java.lang.Object

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

Field Details

operationSet

private static HashSet<FunctionType4.Operation> operationSet

the set of all Operations we support. These operations are defined in Appendix B - Operators.

tokens

private LinkedList tokens

the list of tokens and sub-expressions.

stack

private LinkedList<Object> stack

the stack of operations. The stack contents should all be Comparable.

Constructor Details

FunctionType4

protected FunctionType4()

Creates a new instance of FunctionType4

Method Details

initOperations

private void initOperations()

Initialize the operations that we can perform.

parse

protected void parse(PDFObject obj)
              throws IOException

Read the function information from a PDF Object

Specified by:

parse in class PDFFunction

Throws:

IOException

doFunction

protected void doFunction(float[] inputs,
 int inputOffset,
 float[] outputs,
 int outputOffset)

Map from m input values to n output values. The number of inputs m must be exactly one half the size of the domain. The number of outputs should match one half the size of the range.

Specified by:

doFunction in class PDFFunction

Parameters:

inputs - an array of m input values

inputOffset - the offset into the inputs array to read from

outputs - an array of size n which will be filled with the output values, or null to return a new array

outputOffset - the offset into the output array to write to

popBoolean

private boolean popBoolean()

pushBoolean

private void pushBoolean(boolean arg)

popDouble

private double popDouble()

pushDouble

private void pushDouble(double arg)

popExpression

private FunctionType4.Expression popExpression()

pushExpression

private void pushExpression(FunctionType4.Expression expresson)

popLong

private long popLong()

pushLong

private void pushLong(long arg)

popObject

private Object popObject()

pushObject

private void pushObject(Object obj)

readPS

private void readPS(ByteBuffer buf)

parse the postscript operators and aguments from the stream.

Syntax is to read a set of tokens, including expressions and to queue them as they come including other expressions. Expressions are enclosed in curly brackets and constitute a reference to the expression body.

Parameters:

buf - the stream of postscript tokens