edu.neu.ccs.parser
Class JPTParser

java.lang.Object
  edu.neu.ccs.parser.BaseParser
      edu.neu.ccs.parser.JPTParser

All Implemented Interfaces:

Parser

public class JPTParser

extends BaseParser

Parses and evaulates data Strings using simple expression evaluation.

The grammar used in this parsing is similar to that defined within the Java Language Specification by James Gosling, Bill Joy, and Guy Steele but as of 2.5.0 we have made significant additions to aid the user of these facilities in interactive mode.

As of 2.5.0, the parser algorithms have all been refactored down to the new base class called BaseParser. The purpose of this class is therefore to define and install constants, operations, and functions. Each such entity is now public static final so they may be utilized by some other class that extends BaseParser if so desired.

The constants, functions, and operations are all commented individually. Summary tables of the constants, functions, and operations are provided immediately below and repeated in the comments for the methods addConstants(), addFunctions(), and addOperations(). The summary tables for operations show precedence.

This class now provides an exponentiation operator denoted ^ that attempts exponentiation as an integral computation if possible. This is in contrast to the power function that always uses Math.pow in its implementation. By choosing ^ or power, the user may select implementation.

The function definitions continue to throw exceptions if given incorrect arguments but will no longer throw exceptions if mathematical errors occur. Rather the computation proceeds as in Java itself to produce either an infinity or NaN.

In 2.6.0, added hyperbolic functions.

Constant definitions:

Identifier	Type	Definition
true	XBoolean	true
false	XBoolean	false
pi	XDouble	Math.PI
e	XDouble	Math.E
MaxInt	XInt	Integer.MAX_VALUE
maxint	XInt	Integer.MAX_VALUE
MinInt	XInt	Integer.MIN_VALUE
minint	XInt	Integer.MIN_VALUE
MaxLong	XLong	Long.MAX_VALUE
maxlong	XLong	Long.MAX_VALUE
MinLong	XLong	Long.MIN_VALUE
minlong	XLong	Long.MIN_VALUE
MaxDouble	XDouble	Double.MAX_VALUE
maxdouble	XDouble	Double.MAX_VALUE
MinDouble	XDouble	Double.MIN_VALUE
mindouble	XDouble	Double.MIN_VALUE
Infinity	XDouble	Double.POSITIVE_INFINITY
infinity	XDouble	Double.POSITIVE_INFINITY
NaN	XDouble	Double.NaN
nan	XDouble	Double.NaN

Function definitions:

Function Name	Typical Usage
abs	abs(x)
ceiling	ceiling(x)
floor	floor(x)
round	round(x)
max	max(x,y)
min	min(x,y)
sqrt	sqrt(x)
power	power(x,y)
root	root(x,y)
todegrees	todegrees(theta)
toradians	toradians(angle)
sin	sin(theta)
sindeg	sindeg(angle)
cos	cos(theta)
cosdeg	cosdeg(angle)
tan	tan(theta)
tandeg	tandeg(angle)
asin	asin(s)
asindeg	asindeg(s)
acos	acos(c)
acosdeg	acosdeg(c)
atan	atan(t)
atandeg(t)	atandeg(t)
atan2	atan2(y,x)
atan2deg	atan2deg(y,x)
exp	exp(x)
log	log(x)
ln	ln(x)
log2	log2(x)
log10	log10(x)
logtobase	logtobase(x,b)
sinh	sinh(x)
cosh	cosh(x)
tanh	tanh(x)
asinh	asinh(x)
acosh	acosh(x)
atanh	atanh(x)

In the above table:
x and y stand for generic variables;
theta is an angle in radians;
angle is an angle in degrees;
s, c, t stand for possible values of sin, cos, tan;
and b is the base for a logarithm.

In 2.5.0, random was removed from the list of functions because as implemented in the class AbstractFunction a function has a fixed number of arguments. Instead, random is now implemented directly in BaseParser to take one of three forms with the following interpretations.

Function Name	Typical Usage	Interpretation
random	random()	Random number between 0 and 1
random	random(x)	Random number between 0 and x
random	random(x,y)	Random number between x and y

Operation definitions:

Precedence	Operations	Symbols
0	IDENTITY	None
1	operationOR	||
2	operationAND	&&
3	operationEQ operationNE	== !=
4	operationLT operationGT operationLE operationGE	< > <= >=
5	operationPlus operationMinus	+ -
6	operationTimes operationSlash operationPercent	* / %
7	operationCaret	^
8	operationNOT	!

Since:

1.0

Version:

2.6.0

See Also:

Java Language Specification

Field Summary

static AbstractFunction	functionAbs AbstractFunction to implement abs.
static AbstractFunction	functionACos AbstractFunction to implement acos based on Math.acos.
static AbstractFunction	functionACosDeg AbstractFunction to implement acosdeg based on Math.acos and appropriate radians to degrees conversion.
static AbstractFunction	functionACosh AbstractFunction to implement acosh.
static AbstractFunction	functionASin AbstractFunction to implement asin based on Math.asin.
static AbstractFunction	functionASinDeg AbstractFunction to implement asindeg based on Math.asin and appropriate radians to degrees conversion.
static AbstractFunction	functionASinh AbstractFunction to implement asinh.
static AbstractFunction	functionATan AbstractFunction to implement atan based on Math.atan.
static AbstractFunction	functionATan2 AbstractFunction to implement atan2 based on Math.atan2.
static AbstractFunction	functionATan2Deg AbstractFunction to implement atan2deg based on Math.atan2 and appropriate radians to degrees conversion.
static AbstractFunction	functionATanDeg AbstractFunction to implement atandeg based on Math.atan and appropriate radians to degrees conversion.
static AbstractFunction	functionATanh AbstractFunction to implement atanh.
static AbstractFunction	functionCeiling AbstractFunction to implement ceiling.
static AbstractFunction	functionCos AbstractFunction to implement cos based on Math.cos.
static AbstractFunction	functionCosDeg AbstractFunction to implement cosdeg based on Math.cos and appropriate degrees to radians conversion.
static AbstractFunction	functionCosh AbstractFunction to implement cosh.
static AbstractFunction	functionExp AbstractFunction to implement exp based on Math.exp.
static AbstractFunction	functionFloor AbstractFunction to implement floor.
static AbstractFunction	functionLn AbstractFunction to implement ln based on Math.log.
static AbstractFunction	functionLog AbstractFunction to implement log based on Math.log.
static AbstractFunction	functionLog10 AbstractFunction to implement log10.
static AbstractFunction	functionLog2 AbstractFunction to implement log2.
static AbstractFunction	functionLogToBase AbstractFunction to implement logtobase.
static AbstractFunction	functionMax AbstractFunction to implement max.
static AbstractFunction	functionMin AbstractFunction to implement min.
static AbstractFunction	functionPower AbstractFunction to implement power based on Math.pow.
static AbstractFunction	functionRoot AbstractFunction to implement root based on MathUtilities.root.
static AbstractFunction	functionRound AbstractFunction to implement round.
static AbstractFunction	functionSin AbstractFunction to implement sin based on Math.sin.
static AbstractFunction	functionSinDeg AbstractFunction to implement sindeg based on Math.sin and appropriate degrees to radians conversion.
static AbstractFunction	functionSinh AbstractFunction to implement sinh.
static AbstractFunction	functionSqrt AbstractFunction to implement sqrt based on Math.sqrt.
static AbstractFunction	functionTan AbstractFunction to implement tan based on Math.tan.
static AbstractFunction	functionTanDeg AbstractFunction to implement tandeg based on Math.tan and appropriate degrees to radians conversion.
static AbstractFunction	functionTanh AbstractFunction to implement tanh.
static AbstractFunction	functionToDegrees AbstractFunction to implement todegrees based on Math.toDegrees.
static AbstractFunction	functionToRadians AbstractFunction to implement toradians based on Math.toRadians.
static BooleanOperation	operationAND BooleanOperation to implement "and".
static NumericOperation	operationCaret NumericOperation to implement exponentiation.
static BooleanOperation	operationEQ BooleanOperation to implement equals.
static BooleanOperation	operationGE BooleanOperation to implement greater than or equals.
static BooleanOperation	operationGT BooleanOperation to implement greater than.
static BooleanOperation	operationLE BooleanOperation to implement less than or equals.
static BooleanOperation	operationLT BooleanOperation to implement less than.
static NumericOperation	operationMinus NumericOperation to implement minus.
static BooleanOperation	operationNE BooleanOperation to implement not equals.
static BooleanOperation	operationNOT BooleanOperation to implement "not".
static BooleanOperation	operationOR BooleanOperation to implement "or".
static NumericOperation	operationPercent NumericOperation to implement remainder.
static NumericOperation	operationPlus NumericOperation to implement plus.
static NumericOperation	operationSlash NumericOperation to implement division.
static NumericOperation	operationTimes NumericOperation to implement times.

Fields inherited from class edu.neu.ccs.parser.BaseParser

ARGUMENT_LIST_END, ARGUMENT_LIST_START, ARGUMENT_SEPARATOR, ASSIGNMENT_BY_LET, ASSIGNMENT_BY_SET, data, EVAL, FLOATING, IDENTITY, IF_THEN_ELSE, INTEGRAL, NESTED_EXPRESSION_END, NESTED_EXPRESSION_START, next, OPERATION_PREFIX, RADIX_POINT, RANDOM, suspend, UNDERSCORE

Constructor Summary

JPTParser()

Method Summary

protected void	addConstants() Adds the standard constants for this parser to the environment.
protected void	addFunctions() Adds the standard functions for this parser to the function table.
protected void	addOperations() Adds the standard operations for this parser to the operation table.

Methods inherited from class edu.neu.ccs.parser.BaseParser

addConstant, addFunction, addOperation, addOperationAfterPrecedenceOf, addOperationAtPrecedenceOf, addOperationBeforePrecedenceOf, addReserved, afterDigits, afterSign, assignArgumentList, assignLetVariable, assignSetVariable, assignVariable, call, call, call, call, call, call, call, call, call, call, constants, evaluate, evaluateIdentifier, extractExpression, functionNames, functions, getFunction, getOperation, getValue, initializeStructures, isConstantID, isEnvironmentID, isExponentAt, isFunctionName, isLetVariableID, isOperationOrPrefix, isOperationSymbol, isOrdinaryFunctionName, isPossibleIdentifier, isPossibleOperation, isPossibleVariableID, isReservedID, isSetVariableID, isSignAt, isSimpleFunctionName, makeTable, makeTable, makeTable, makeTable, nextIdentifier, nextOperation, nextSimpleTerm, nextTerm, nextTokenIs, nextTokenIs, nextUnaryOperations, operations, operationSymbols, ordinaryFunctionNames, ordinaryFunctions, parse, parseArgumentList, parseAssignment, parseEval, parseExpression, parseExpression, parseFunctionCall, parseIdentifierExpression, parseIdentifierExpressionList, parseIfThenElse, parseNestedExpression, parseNumber, parseRandom, parseSpecialFunction, parseWithArgumentList, popContext, precedenceOf, pushContext, removeFunction, reserved, reserveID, set_variables, setArgumentSeparatorToken, setLeftParenthesisToken, setRadixPointToken, setRightParenthesisToken, simpleFunctionNames, simpleFunctions, simpleFunctionsToString, skipWhitespace, specialPush, startsIdentifier, startsNumber, stringToSimpleFunctions, throwAgainAndPop, withinIdentifier

Methods inherited from class java.lang.Object

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

Field Detail

functionAbs

public static final AbstractFunction functionAbs

AbstractFunction to implement abs.

functionCeiling

public static final AbstractFunction functionCeiling

AbstractFunction to implement ceiling.

functionFloor

public static final AbstractFunction functionFloor

AbstractFunction to implement floor.

functionRound

public static final AbstractFunction functionRound

AbstractFunction to implement round.

functionMax

public static final AbstractFunction functionMax

AbstractFunction to implement max.

functionMin

public static final AbstractFunction functionMin

AbstractFunction to implement min.

functionSqrt

public static final AbstractFunction functionSqrt

AbstractFunction to implement sqrt based on Math.sqrt.

functionPower

public static final AbstractFunction functionPower

AbstractFunction to implement power based on Math.pow.

See Also:

operationCaret

functionRoot

public static final AbstractFunction functionRoot

AbstractFunction to implement root based on MathUtilities.root.

functionToDegrees

public static final AbstractFunction functionToDegrees

AbstractFunction to implement todegrees based on Math.toDegrees.

functionToRadians

public static final AbstractFunction functionToRadians

AbstractFunction to implement toradians based on Math.toRadians.

functionSin

public static final AbstractFunction functionSin

AbstractFunction to implement sin based on Math.sin.

functionSinDeg

public static final AbstractFunction functionSinDeg

AbstractFunction to implement sindeg based on Math.sin and appropriate degrees to radians conversion.

functionCos

public static final AbstractFunction functionCos

AbstractFunction to implement cos based on Math.cos.

functionCosDeg

public static final AbstractFunction functionCosDeg

AbstractFunction to implement cosdeg based on Math.cos and appropriate degrees to radians conversion.

functionTan

public static final AbstractFunction functionTan

AbstractFunction to implement tan based on Math.tan.

functionTanDeg

public static final AbstractFunction functionTanDeg

AbstractFunction to implement tandeg based on Math.tan and appropriate degrees to radians conversion.

functionASin

public static final AbstractFunction functionASin

AbstractFunction to implement asin based on Math.asin.

functionASinDeg

public static final AbstractFunction functionASinDeg

AbstractFunction to implement asindeg based on Math.asin and appropriate radians to degrees conversion.

functionACos

public static final AbstractFunction functionACos

AbstractFunction to implement acos based on Math.acos.

functionACosDeg

public static final AbstractFunction functionACosDeg

AbstractFunction to implement acosdeg based on Math.acos and appropriate radians to degrees conversion.

functionATan

public static final AbstractFunction functionATan

AbstractFunction to implement atan based on Math.atan.

functionATanDeg

public static final AbstractFunction functionATanDeg

AbstractFunction to implement atandeg based on Math.atan and appropriate radians to degrees conversion.

functionATan2

public static final AbstractFunction functionATan2

AbstractFunction to implement atan2 based on Math.atan2.

functionATan2Deg

public static final AbstractFunction functionATan2Deg

AbstractFunction to implement atan2deg based on Math.atan2 and appropriate radians to degrees conversion.

functionExp

public static final AbstractFunction functionExp

AbstractFunction to implement exp based on Math.exp.

functionLog

public static final AbstractFunction functionLog

AbstractFunction to implement log based on Math.log.

This is identical to ln.

functionLn

public static final AbstractFunction functionLn

AbstractFunction to implement ln based on Math.log.

This is identical to log.

functionLog2

public static final AbstractFunction functionLog2

AbstractFunction to implement log2.

log2(x) is computed as:

Math.log(x) / Math.log(2)

functionLog10

public static final AbstractFunction functionLog10

AbstractFunction to implement log10.

log10(x) is computed as:

Math.log(x) / Math.log(10)

functionLogToBase

public static final AbstractFunction functionLogToBase

AbstractFunction to implement logtobase.

logtobase(x,b) is computed as:

Math.log(x) / Math.log(b)

functionSinh

public static final AbstractFunction functionSinh

AbstractFunction to implement sinh.

sinh(x) is computed as:

MathUtilities.sinh(x)

functionCosh

public static final AbstractFunction functionCosh

AbstractFunction to implement cosh.

cosh(x) is computed as:

MathUtilities.cosh(x)

functionTanh

public static final AbstractFunction functionTanh

AbstractFunction to implement tanh.

tanh(x) is computed as:

MathUtilities.tanh(x)

functionASinh

public static final AbstractFunction functionASinh

AbstractFunction to implement asinh.

asinh(x) is computed as:

MathUtilities.asinh(x)

functionACosh

public static final AbstractFunction functionACosh

AbstractFunction to implement acosh.

acosh(x) is computed as:

MathUtilities.acosh(x)

functionATanh

public static final AbstractFunction functionATanh

AbstractFunction to implement atanh.

atanh(x) is computed as:

MathUtilities.atanh(x)

operationPlus

public static final NumericOperation operationPlus

NumericOperation to implement plus.

Symbol: "+".

Unary and binary.

operationMinus

public static final NumericOperation operationMinus

NumericOperation to implement minus.

Symbol: "-".

Unary and binary.

operationTimes

public static final NumericOperation operationTimes

NumericOperation to implement times.

Symbol: "*".

Binary.

operationSlash

public static final NumericOperation operationSlash

NumericOperation to implement division.

Symbol: "/".

Binary.

operationPercent

public static final NumericOperation operationPercent

NumericOperation to implement remainder.

Symbol: "%".

Binary.

operationCaret

public static final NumericOperation operationCaret

NumericOperation to implement exponentiation.

Symbol: "^".

Binary.

If the arguments are integral, that is, of type XBigInteger, then an effort will be made to carry out the exponentiation in integral arithmetic.

If the arguments are not integral or if it is impossible to do an integral computation, then this method reverts to using Math.pow.

This operation is more subtle than the function functionPower introduced in this class. The power function always uses Math.pow and makes no attempt to handle integral arguments in a special way.

It is intentional that this operation and the power function operate differently. In some cases, the user may want an integral computation but in other cases if the internal BigInteger would be extremely large may actually perfer to do the computation using double precision floating point.

See Also:

functionPower

operationEQ

public static final BooleanOperation operationEQ

BooleanOperation to implement equals.

Symbol: "==".

Binary. All types.

operationNE

public static final BooleanOperation operationNE

BooleanOperation to implement not equals.

Symbol: "!=".

Binary. All types.

operationLT

public static final BooleanOperation operationLT

BooleanOperation to implement less than.

Symbol: "<".

Binary. All types.

operationGT

public static final BooleanOperation operationGT

BooleanOperation to implement greater than.

Symbol: ">".

Binary. All types.

operationLE

public static final BooleanOperation operationLE

BooleanOperation to implement less than or equals.

Symbol: "<=".

Binary. All types.

operationGE

public static final BooleanOperation operationGE

BooleanOperation to implement greater than or equals.

Symbol: ">=".

Binary. All types.

operationAND

public static final BooleanOperation operationAND

BooleanOperation to implement "and".

Symbol: "&&".

Binary. Boolean only.

operationOR

public static final BooleanOperation operationOR

BooleanOperation to implement "or".

Symbol: "||".

Binary. Boolean only.

operationNOT

public static final BooleanOperation operationNOT

BooleanOperation to implement "not".

Symbol: "!".

Binary. Boolean only.

Constructor Detail

JPTParser

public JPTParser()

Method Detail

addConstants

protected void addConstants()

Adds the standard constants for this parser to the environment.

Identifier	Type	Definition
true	XBoolean	true
false	XBoolean	false
pi	XDouble	Math.PI
e	XDouble	Math.E
MaxInt	XInt	Integer.MAX_VALUE
maxint	XInt	Integer.MAX_VALUE
MinInt	XInt	Integer.MIN_VALUE
minint	XInt	Integer.MIN_VALUE
MaxLong	XLong	Long.MAX_VALUE
maxlong	XLong	Long.MAX_VALUE
MinLong	XLong	Long.MIN_VALUE
minlong	XLong	Long.MIN_VALUE
MaxDouble	XDouble	Double.MAX_VALUE
maxdouble	XDouble	Double.MAX_VALUE
MinDouble	XDouble	Double.MIN_VALUE
mindouble	XDouble	Double.MIN_VALUE
Infinity	XDouble	Double.POSITIVE_INFINITY
infinity	XDouble	Double.POSITIVE_INFINITY
NaN	XDouble	Double.NaN
nan	XDouble	Double.NaN

Overrides:

addConstants in class BaseParser

addFunctions

protected void addFunctions()

Adds the standard functions for this parser to the function table.

Function Name	Typical Usage
abs	abs(x)
ceiling	ceiling(x)
floor	floor(x)
round	round(x)
max	max(x,y)
min	min(x,y)
sqrt	sqrt(x)
power	power(x,y)
root	root(x,y)
todegrees	todegrees(theta)
toradians	toradians(angle)
sin	sin(theta)
sindeg	sindeg(angle)
cos	cos(theta)
cosdeg	cosdeg(angle)
tan	tan(theta)
tandeg	tandeg(angle)
asin	asin(s)
asindeg	asindeg(s)
acos	acos(c)
acosdeg	acosdeg(c)
atan	atan(t)
atandeg(t)	atandeg(t)
atan2	atan2(y,x)
atan2deg	atan2deg(y,x)
exp	exp(x)
log	log(x)
ln	ln(x)
log2	log2(x)
log10	log10(x)
logtobase	logtobase(x,b)
sinh	sinh(x)
cosh	cosh(x)
tanh	tanh(x)
asinh	asinh(x)
acosh	acosh(x)
atanh	atanh(x)

In the above table:
x and y stand for generic variables;
theta is an angle in radians;
angle is an angle in degrees;
s, c, t stand for possible values of sin, cos, tan;
and b is the base for a logarithm.

In 2.5.0, random was removed from the list of functions because as implemented in the class AbstractFunction a function has a fixed number of arguments. Instead, random is now implemented directly in BaseParser to take one of three forms with the following interpretations.

Function Name	Typical Usage	Interpretation
random	random()	Random number between 0 and 1
random	random(x)	Random number between 0 and x
random	random(x,y)	Random number between x and y

Overrides:

addFunctions in class BaseParser

addOperations

protected void addOperations()

Adds the standard operations for this parser to the operation table.

Except for the introduction of the ^ operation, follows Arnold, Gosling, Holmes:

The Java Programming Language, Third Edition, 6.10

Precedence	Operations	Symbols
0	IDENTITY	None
1	operationOR	||
2	operationAND	&&
3	operationEQ operationNE	== !=
4	operationLT operationGT operationLE operationGE	< > <= >=
5	operationPlus operationMinus	+ -
6	operationTimes operationSlash operationPercent	* / %
7	operationCaret	^
8	operationNOT	!

Overrides:

addOperations in class BaseParser

See Also:

operationCaret