Class Utils

MathParser/src/com/aghajari/math/Utils.java:25–215

import java.util.regex.Pattern;

public class Utils {

    /* used to check if parentheses are balanced */
    //public final static Pattern balancedParentheses = Pattern.compile("\\((?:[^)(]+|\\((?:[^)(]+|\\([^)(]*\\))*\\))*\\)");
    /* used to find the innermost parentheses */
    public final static Pattern innermostParentheses = Pattern.compile("(\\([^\\(]*?\\))");
    /* used to split function arguments by comma */
    public final static Pattern splitParameters = Pattern.compile(",(?=(?:[^()]*\\([^()]*\\))*[^\\()]*$)");
    /* used to split if condition to two comparable part */
    public final static Pattern splitIf = Pattern.compile("(.*?)(!=|<>|>=|<=|==|>|=|<)(.*?$)");
    /* used to simplify double type values */
    public final static Pattern doubleType = Pattern.compile("\\(([\\d.]+([eE])[\\d+-]+)\\)");
    /* used to simplify binary values */
    public final static Pattern binary = Pattern.compile("\\(0b[01]+\\)");
    /* used to simplify octal values */
    public final static Pattern octal = Pattern.compile("\\(0o[0-7]+\\)");
    /* used to simplify hexadecimal values */
    public final static Pattern hexadecimal = Pattern.compile("\\(0x[0-9a-fA-F]+\\)");

    /**
     * @param src the expression to check
     * @throws BalancedParenthesesException If parentheses aren't balanced
     */
    public static void validateBalancedParentheses(String src) throws BalancedParenthesesException {
        /*String dest = src.replaceAll(balancedParentheses.pattern(), "");
        if (dest.contains(")"))
            throw new BalancedParenthesesException(src, src.indexOf(dest.substring(dest.indexOf(")"))) + 1);
        else if (dest.contains("("))
            throw new BalancedParenthesesException(src, src.indexOf(dest.substring(dest.indexOf("("))) + 1);*/

        if (Utils.realTrim(src).contains("()"))
            throw new BalancedParenthesesException(null, -1);

        int opened = 0;
        for (int i = 0; i < src.length(); ++i)
            if (src.charAt(i) == '(')
                opened++;
            else if (src.charAt(i) == ')') {
                opened--;
                if (opened < 0)
                    throw new BalancedParenthesesException(src, i + 1);
            }

        if (opened != 0)
            throw new BalancedParenthesesException(src, src.length());
    }

    /**
     * @see jdk.internal.joptsimple.internal.Strings#repeat(char, int)
     */
    public static String repeat(char ch, int count) {
        StringBuilder buffer = new StringBuilder();

        for (int i = 0; i < count; ++i)
            buffer.append(ch);

        return buffer.toString();
    }