ValidateCpf.java

public class ValidateCpf{

    private String cpf;
    private int resultSm;
    private int resultOnDigit;
    private int resultTwoDigit;

    public ValidateCpf(String cpf){
        // Set attribute CPF
        this.cpf = cpf;

        // Action methods
        this.setResultSm();
        this.setResultOnDigit();
        this.setResultTwoDigit();
    }

    /***
     *
     * @return true or false;
     */
    public boolean isCpf(){
        int lenghtCpf = this.cpf.length();

        String digitChecker = this.cpf.substring(lenghtCpf -2, lenghtCpf);

        String digitCheck = resultOnDigit +""+resultTwoDigit;

        boolean situation = false;
        if(digitChecker.equals(digitCheck)){
            situation = true;
        }

        return situation;
    }
    /***
     *  Set result calculate SM
     */
    private void setResultSm(){
        // Set attribute result SM
        this.resultSm = this.calculate(this.cpf, 9, 10);
    }

    /***
     * Set result calculate digit CPF
     */
    private void setResultOnDigit(){
        // Set Result On Digit checker CPF
        int calculateOneDigit = 11 - (this.resultSm % 11);

        this.resultOnDigit = calculateOneDigit == 11 || calculateOneDigit == 10 ? 0 : calculateOneDigit;
    }

    /**
     *
     */
    private void setResultTwoDigit(){
        int calculateTwo = this.calculate(this.cpf, 10, 11);

        int calculateTwoDigit = 11 - (calculateTwo % 11);

        this.resultTwoDigit = calculateTwoDigit == 11 || calculateTwoDigit == 10 ? 0 : calculateTwoDigit;
    }

    /***
     * Calculate - performs the multiplication of numbers
     * @param cpf
     * @param num_cpf
     * @param weight
     * @return
     */
    private int calculate(String cpf, int num_cpf, int weight){

        // Variable stores result calculate
        int resultCalculate = 0;

        for(int i=0; i < num_cpf; i++){

            // Convert char in String
            String stringCpf = Character.toString(cpf.charAt(i));

            resultCalculate += Integer.parseInt(stringCpf) * weight;

            weight--;
        }

        return resultCalculate;
    }

    /***
     *  Use instruction class ValidateCpf
     *
     *          // String CPF
     *         String cpf = "03930735059";
     *
     *         // Instance Class and get param construct
     *         ValidateCpf checkCpf = new ValidateCpf(cpf);
     *
     *         // Checker CPF @return true or false.
     *         System.out.println(checkCpf.isCpf());
     */
}