Page Comparison

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S → SS
S → (S)
S → ()
S → key KEY
KEY → operator OPERATOR
OPERATOR → value VALUE
OPERATOR → value
VALUE → value VALUE
VALUE → value
VALUE → and AND
VALUE → or OR
AND → S
OR → S

Psuedocode

TSymbolType

A representation for an enum that declares the type of a TSymbol.

enum TSymbolType {
	CONJUNCTION = 1,
	KEY = 2,
	VALUE = 3
}

TSymbol

A representation for a Symbol that can be passed over the wire via Thrift. Once passed over the wire, the server uses information about the symbol type to parse the string representation of the symbol to an actual object.

struct TSymbol {
	1:required TSymbolType type; 
	2:required string symbol;
}

TCriteria

A representation for a Criteria that can be passed over the wire via Thrift. Once passed over the write, the server goes through the list of TSymbols and converts them to actual Symbol objects which can then be used in the shunting-yard algorithm.

struct TCriteria {
	1:required list<TSymbol> symbols
}

Criteria

A wrapper around an in-order collection of symbols. A Criteria is generated from the completion of a state machine that comprises a builder.

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A marker interface to indicate an object that can be included in a Criteria

interface Symbol {} //marker interface

Conjunction

An enum that represents the possible conjunction symbols.Criteria

enum Conjunction implementsinterface Symbol {
	AND, OR;
}

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} //marker interface

Conjunction

An enum that represents the possible parenthesis conjunction symbols.

enum ParenthesisConjunction implements Symbol {
	LEFTAND, RIGHTOR;
}

Key

A symbol that represents a "key" in a Criteria.

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