Thread: Java calculator implementation

am basically attempting to create a calculator using a class hierarchy - the basic function will be:

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 -

numbers operators and brackets.

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

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

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

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

I also need help in creating my own stacks and queues.

Thanks

Hi thanks for the help.

How would I implement my own stack without using the java utils?

also what sort of hierarchy should i use? I was thinking maybe a filereader class and then one to deal with the objects and then a main to tie it all together?

thanks again

so my thinking now is to have the following classes:

stack class
main - filereading, dealing with the numbers+operands
shunting yard class

Is this an acceptable sort of hierarchy?

thanks

Originally Posted by why_always_me

so my thinking now is to have the following classes:

stack class
main - filereading, dealing with the numbers+operands
shunting yard class

Is this an acceptable sort of hierarchy?

thanks

Hi Guys my new thinking is :

List class
Node class
Shunting yard class
Main class
Main includes the reverse Polich notation, filereader and tokenizer.

My question now is how would i link main to the shunting yard? I was told I should create a list of objects which will be numbers, operands and brackets. Thanks again

you can create instances of you class in your main. then you can use those instances to perform whatever you need to.
i.e.

...main()
{
ShuntingYard var1;
.....
}