Java Convert double to int

Question

I have this code, and the input in the textfield is 50, so its output should be 25,
but there is a error, because no output

button_1.addActionListener(new ActionListener() {
    String tfg = textField.getText().toString();
    String tfc = textField.getText();

    public void actionPerformed(ActionEvent e) {
        if(textField.getText().toString().equals("0") || 
            textField.getText().toString().equals("") || 
            textField.getText().toString().equals(" ") || 
            textField.getText().toString().matches("[a-zA-Z]+")) {
            JOptionPane.showMessageDialog(Cow.this,
                            "Tree Amount Should Be 1 or More",
                            "Invalid Tree Amount",
                            JOptionPane.ERROR_MESSAGE);
        }

        if(!tfg.equals("0")) {
            try {
                int tfgg = Integer.parseInt(tfc);
                int trcs = tfgg * 1;
                double trcp = 1 / 2;
                int trcc = (int) trcp * trcs;
                System.out.println(new Integer(trcc).toString());
            } catch (NumberFormatException se) {

            }
        }
    }
});

I try to convert from my php to that code, here is my php code :

$doorSeed = $mount * 1;
$doorPrice = 1 / 2;
$doorConvert = $doorPrice * $doorSeed;
echo "Treasure Chest Seed = ".$doorSeed." Price : ".$doorConvert." World Lock <br>";

Answer 1

int trcc = (int) trcp * trcs;

Try this instead

int trcc = (int) (trcp * trcs);

You need to cast the complete expression [(trcp * trcs)] instead of just the first variable trcp to int. The other variable in the expression trcs is of double type, so the result of the expression become double. That is why you cast the complete expression. So your end result will be int

     int tfgg = Integer.parseInt(tfc.trim());    // tfc = 4;   tfgg = 4;
     int trcs = tfgg * 1;                 // trcs = 4 * 1 = 5;
     double trcp = 1.0 / 2;               // trcp = 0.5;
     int trcc = (int) (trcp * trcs);      // trcc = (0.5 * 5) = (2.5) = 2;
     System.out.println(trcc);            // 2;

double trcp = 1.0 / 2;

Here make at least one value as double so the expression will be evaluated as double as suggested by @tunaki.

Also you don't need this statement in your code int trcs = tfgg * 1;.

Use like this:

  String tfg ;
  String tfc ;
  public void actionPerformed(ActionEvent e) {
    tfg = textField.getText();
    tfc = textField.getText();
    if(textField.getText().equals("0") || textField.getText().equals("") || textField.getText().equals(" ") || textField.getText().matches("[a-zA-Z]+")) {
      JOptionPane.showMessageDialog(Cow.this,
          "Tree Amount Should Be 1 or More",
          "Invalid Tree Amount",
          JOptionPane.ERROR_MESSAGE);
    }
    if(!tfg.equals("0")) {
      try {
        int tfgg = Integer.parseInt(tfc.trim());    // tfc = 4;
        int trcs = tfgg;                 // trcs = 4 * 1 = 5
        double trcp = 1.0 / 2;                 // trcp = 0.5
        int trcc = (int) (trcp * trcs);      // trcc = (0.5 * 5) = (2.5) = 2
        System.out.println("HI: "+trcc);
      } catch (NumberFormatException ignored) {
      }

Answer 2

Your problem is at this line:

double trcp = 1 / 2;

This does not result in trcp = 0.5 but trcp = 0.0, because you are dividing integer values (and so are using integer division).

You should use the following code:

double trcp = 1.0 / 2;

to force division using doubles.

Other comments:

• new Integer(trcc).toString() should be replaced with String.valueOf(trcc).
• Avoid using empty catch statements: at minimum, log the exception
• What's the point of this line: int trcs = tfgg * 1;?

Answer 3

Basically you have this (int)0.5 = 0. In your case, trcp = 0.5 and is double, so when it's cast to integer the result is 0.

And when you do (int)a + b, the true operation with parenthesis for priority here is: ((int)a)+(b), so what you have to is the following:

int trcc = (int) (trcp * trcs);

instead of the following:

int trcc = (int) trcp * trcs;