package lists;

public class Token
{
    static String OPS = "+-*/^";
    static String DIGITS = "0123456789";
    
    private String value;
    
    public Token(char value)
    {
        this.value = String.valueOf(value);
    }
    
    public Token(String value)
    {
        this.value = value;
    }
    
    boolean isOperator()
    {
        return (OPS.indexOf(value) >= 0);
    }
    
    static boolean isOperator(char c)
    {
        return (OPS.indexOf(c) >= 0);
    }
    
    static boolean isDigit(char c)
    {
        return (DIGITS.indexOf(c) >= 0);
    }
   
    
    boolean isNumber()
    {
        return (OPS.indexOf(value) < 0);
    }
    
    int getNumber()
    {
        return Integer.parseInt(value);
    }
    
    char getOperator()
    {
        return value.charAt(0);
    }
    
    int getPrecedence()
    {
        if (isNumber())
            return 0;
        else if ((value.equals("+")) || (value.equals("-")))
            return 1;
        else if ((value.equals("*")) || (value.equals("/")))
            return 2;
        else
            return 3;
    }
    
    public String toString()
    {
        if (isOperator())
            return value + " [operator, precedence " + getPrecedence() + "]";
        else
            return value + " [number, precedence " + getPrecedence() + "]";           
    }
}