/**
An interface for classes which provide the service of accumulating strings bit by bit. The notional state of a string accumulator is a string; his is initially empty, and when {@link #accumulate} is called, the toString of the argument is added to the end of the state.
*/
public interface StringAccumulator {
	
	/**
	Adds the toString of the parameter to the accumulator.
	
	@param	obj	the object whose toString to accumulate; this may not be null
	*/
	public void accumulate(Object obj);
	
	/**
	Exactly the same as {@link #accumulate(java.lang.Object)}. Provided as a convenience.
	
	@param	str	the string to accumulate; this may not be null
	*/
	public void accumulate(String str);
	
	/**
	@return	the 
	@throws	{@link java.lang.IllegalStateException}	if toString has already been called and this accumulator does not support repeated toStringing
	*/
	public String toString();
	
}