Java calculator class hierarchy issue
<p>am basically attempting to create a calculator using a class hierarchy - the basic function will be:</p>

<p>Convert the String representation into a list of Tokens
Convert the List of Tokens into Polish Notation
Calculate the result on the basis of Polish Notation
I also need to represent objects -</p>

<p>numbers operators and brackets.</p>

<p>Following this i need to convert to polish notation - using a shunting yard algorithm and then compute the answer.</p>

<p>I am ok with understanding the shunting yard but am unsure as to the class hierarchy part.</p>

<p>The precedence is - Addition and Subtraction have a precedence of 2, and Multiplication and Division have a precedence of 3.</p>

<p>I am assuming i need a filereader class and also classes to handle the different objects.</p>

<p>I also need help in creating my own stacks and queues.</p>

<p>Thanks</p>
