Computation with IF, ELSE IF Statements

Question

I have no idea why i cannot get the correct way to code my simple computation with if and else if statements.

All of the variables just return a "0.0" value which I can't guess what's wrong? Can you help me guys solve this problem please?

This is my code:

public class MonthlyComputation extends MyActivity
{
String civil_status;

public void DoComputation()
{

    final EditText net_salary = (EditText) findViewById(R.id.et_net_monthly);
    final EditText tax_due = (EditText) findViewById(R.id.et_taxdue);
    final Button btn_compute = (Button) findViewById(R.id.btn_compute_from_monthly);
    final TextView txt3 = (TextView) findViewById(R.id.textView3);
    final TextView txt4 = (TextView) findViewById(R.id.textView4);

    final TextView txt5 = (TextView) findViewById(R.id.textView5);
    final TextView txt6 = (TextView) findViewById(R.id.textView6);


    btn_compute.setOnClickListener(new Button.OnClickListener()
    {

        @Override
        public void onClick(View v)
        {

            double netSalary, taxDue, rate = 0, exemption = 0, subtrahend = 0, withRate;
            String ns, td, r, e, s, wr;

            ns = net_salary.getText().toString();
            netSalary = Double.parseDouble(ns);

            /* Single or Married with no dependent */

            if ((civil_status == "SME") && (netSalary >= 4167) && (netSalary < 5000))
            {
                rate = 0.05;
                exemption = 0.00;
                subtrahend = 4167;
            }

            else if ((civil_status == "SME") && (netSalary >= 5000) && (netSalary < 6667))
            {
                rate = 0.1;
                exemption = 41.67;
                subtrahend = 5000;
            }

            taxDue = netSalary - subtrahend;
            withRate = taxDue * rate;
            taxDue = withRate + exemption;
            tax_due.setText(Double.toString(taxDue));

            td = String.valueOf(taxDue);
            e = String.valueOf(exemption);
            s = String.valueOf(subtrahend);
            r = String.valueOf(rate);

            txt3.setText(td);
            txt4.setText(e);
            txt5.setText(s);
            txt6.setText(r);

        }
    });
}

score 12 · Accepted Answer · edited May 23 '17 at 12:18

NEVER EVER use == to compare String (and objects in general), you'll most probably get false because it compares object references, not values.

See this other question for more information: Java String.equals versus ==

The solution? Use .equals() instead:

...
if ("SME".equals(civil_status) && (netSalary >= 4167) && (netSalary < 5000))
{
    rate = 0.05;
    exemption = 0.00;
    subtrahend = 4167;
}
...

Computation with IF, ELSE IF Statements

1 Answers1