com.eteks.parser
Class DefaultSyntax

java.lang.Object
  |
  +--com.eteks.parser.AbstractSyntax
        |
        +--com.eteks.parser.DefaultSyntax

All Implemented Interfaces:

Syntax

Direct Known Subclasses:

PascalSyntax

public class DefaultSyntax

extends AbstractSyntax

Default syntax used by parsers for functions and expressions. This syntax supports the following operators, constants and functions :

• Unary operators : + -
• Binary operators : ^ * / MOD + - (from the highest to the lowest priority)
• No condition
• Constants : PI FALSE TRUE
• Functions : LN LOG EXP SQR SQRT COS SIN TAN ACOS ASIN ATAN COSH SINH TANH INT ABS OPP

The literals may be any decimal or integer number. The operator for assignment is =, brackets ( ) and the separator of parameters ,.
The parsed identifiers (name of a function and its parameters) may contain letters, digits, or the character _. The first character can't be a digit.
This syntax isn't case sensitive. A DefaultSyntax object may be modified with the methods of AbstractSyntax.

Since:

Jeks 1.0

Version:

1.0

Author:

Emmanuel Puybaret

Fields inherited from interface com.eteks.parser.Syntax

CONDITION_ELSE, CONDITION_IF, CONDITION_THEN, CONSTANT_E, CONSTANT_FALSE, CONSTANT_PI, CONSTANT_TRUE, FUNCTION_ABS, FUNCTION_ACOS, FUNCTION_ASIN, FUNCTION_ATAN, FUNCTION_CEIL, FUNCTION_COS, FUNCTION_COSH, FUNCTION_EXP, FUNCTION_FLOOR, FUNCTION_INTEGER, FUNCTION_LN, FUNCTION_LOG, FUNCTION_NOT, FUNCTION_OPPOSITE, FUNCTION_ROUND, FUNCTION_SIN, FUNCTION_SINH, FUNCTION_SQR, FUNCTION_SQRT, FUNCTION_TAN, FUNCTION_TANH, OPERATOR_ADD, OPERATOR_BITWISE_AND, OPERATOR_BITWISE_NOT, OPERATOR_BITWISE_OR, OPERATOR_BITWISE_XOR, OPERATOR_DIFFERENT, OPERATOR_DIVIDE, OPERATOR_EQUAL, OPERATOR_GREATER, OPERATOR_GREATER_OR_EQUAL, OPERATOR_LESS, OPERATOR_LESS_OR_EQUAL, OPERATOR_LOGICAL_AND, OPERATOR_LOGICAL_NOT, OPERATOR_LOGICAL_OR, OPERATOR_LOGICAL_XOR, OPERATOR_MODULO, OPERATOR_MULTIPLY, OPERATOR_OPPOSITE, OPERATOR_POSITIVE, OPERATOR_POWER, OPERATOR_REMAINDER, OPERATOR_SHIFT_LEFT, OPERATOR_SHIFT_RIGHT, OPERATOR_SHIFT_RIGHT_0, OPERATOR_SUBSTRACT, USER_STARTING_KEY

Constructor Summary

DefaultSyntax()
Creates a default syntax.

Method Summary

java.lang.Object	getLiteral(java.lang.String expression, java.lang.StringBuffer extractedLiteral) Returns the value of the number parsed from the string expression or null if expression doesn't start with a number.
boolean	isDigit(char character) Returns true if character is a digit.
boolean	isLetter(char character) Returns true if character is a letter.
boolean	isValidIdentifier(java.lang.String identifier) Returns true if identifier is a correct name of function or parameter.

Methods inherited from class com.eteks.parser.AbstractSyntax

addFunction, getAssignmentOperator, getBinaryOperatorKey, getBinaryOperatorPriority, getClosingBracket, getCommonFunctionKey, getConditionPartCount, getConditionPartKey, getConstantKey, getDelimiters, getFunction, getOpeningBracket, getParameterSeparator, getUnaryOperatorKey, getWhiteSpaceCharacters, isCaseSensitive, isShortSyntax, removeFunction, setAssignmentOperator, setBinaryOperatorKey, setBinaryOperatorPriority, setClosingBracket, setCommonFunctionKey, setConditionPartKey, setConstantKey, setOpeningBracket, setParameterSeparator, setShortSyntax, setUnaryOperatorKey, setWhiteSpaceCharacters

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultSyntax

public DefaultSyntax()

Creates a default syntax.

Method Detail

getLiteral

public java.lang.Object getLiteral(java.lang.String expression,
                                   java.lang.StringBuffer extractedLiteral)

Returns the value of the number parsed from the string expression or null if expression doesn't start with a number. If a number is found at the beginning of expression, this method extracts it in the string buffer extractedLiteral.

Parameters:

expression - the string to parse.

extractedLiteral - the literal extracted from expression identified as a valid number with the getLiteralNumber () method of the AbstractSyntax class. This string buffer is emptied before the call of this method by the parser.

Returns:

the value of the extracted number or null if expression doesn't start with a number.

See Also:

com.eteks.parser.AbstractSyntax#getLiteralNumber

isValidIdentifier

public boolean isValidIdentifier(java.lang.String identifier)

Returns true if identifier is a correct name of function or parameter. identifier may contain letters, digits, or the character _. Its first character can't be a digit.

Parameters:

identifier - the string to test.

Returns:

true if identifier is a correct identifier.

isLetter

public boolean isLetter(char character)

Returns true if character is a letter. By default letters are limited to ASCII letters (a to z or A to Z). Override this method to have a syntax with a richer set of letters.

Parameters:

character - a char to test.

Returns:

true if character is an ASCII letter (a to z or A to Z).

isDigit

public boolean isDigit(char character)

Returns true if character is a digit. By default digits are limited to ASCII digits (1 to 9). Override this method to have a syntax with a richer set of digits.

Parameters:

character - a char to test.

Returns:

true if character is an ASCII digit (1 to 9).