org.norecess.citkit.symboltable
Interface SymbolTable<A>

All Known Implementing Classes:

EmptySymbolTable, HashSymbolTable

public interface SymbolTable<A>

Method Summary

void	add(java.lang.String name, A value) Adds a name with an associated value to the current symbol table..
void	add(Symbol variable, A value) Adds a new variable to the current symbol table.
A	get(ISymbol variable) Returns the value associated with the specified variable.
A	get(java.lang.String name) Returns the value associated with the specified variable.
java.util.Set<Symbol>	getSymbols() Returns all of symbols from the current scope.
java.lang.String	getVariablesAsString() Returns just the variables of the scope.
A	set(java.lang.String name, A value) Sets a value associated with a name.
A	set(Symbol variable, A value) Changes the value associated with the specified variable.

Method Detail

add

void add(Symbol variable,
         A value)

Adds a new variable to the current symbol table. This does not check the previous symbol table (for previous variable scopes) to see if this shadows an earlier declaration; an exception is thrown when the variable is already declared in the current symbol table.

Parameters:

variable - the new variable to add to the symbol table.

value - the new value to associate with the new variable.

Throws:

java.lang.IllegalStateException - when the variable is already declared in the current symbol table.

add

void add(java.lang.String name,
         A value)

Adds a name with an associated value to the current symbol table..

See Also:

add(Symbol, Object)

get

A get(ISymbol variable)

Returns the value associated with the specified variable. The search for the variable starts in the current symbol table; if it's found, that value is returned; otherwise, the search continued (recursively) through the previous symbol tables. The method returns null for an undefined variable.

Parameters:

variable - the variable to search for.

Returns:

the value associated with the variable; null if the variable isn't found.

get

A get(java.lang.String name)

Returns the value associated with the specified variable.

See Also:

get(ISymbol)

getSymbols

java.util.Set<Symbol> getSymbols()

Returns all of symbols from the current scope.

set

A set(Symbol variable,
      A value)

Changes the value associated with the specified variable. The variable is searched for in all of the previous symbol tables starting with the current one; the old value associated with the variable is returned.

Parameters:

variable - the variable to search for.

value - the new value for the variable.

Returns:

the old value associated with the variable.

set

A set(java.lang.String name,
      A value)

Sets a value associated with a name.

See Also:

set(Symbol, Object)

getVariablesAsString

java.lang.String getVariablesAsString()

Returns just the variables of the scope. Useful in debugging.