جافا

What is required: Write a Java class that performs the following flow of tasks: 1. Reads a set of mathematical expressions from an input text file. For example the input file can be something like this: 2. Convert every mathematical expression into postfix expression. (2+3)*4 (5-2)/(2-1) 4+9 2*(6+1)*(2+3) 2 3. Create a stack data structure and use to evaluate every postfix expression. Make sure to use just one stack that should be flushed every time you calculate an expression to calculate the next. 4. The result of every expression should be written to an output file (on a separated line) in the same order of the input expressions.