'else' Not Required

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'else' is not required

Form

   if (condition) {
      do this if the condition is true
   }

Example

public void paintComponent(Graphics g) {
  super.paintComponent(g);  // draw background etc.
  if (marks < 50) {
     g.setColor(Color.red);
  }
  g.drawString("Score = " + marks, 10, 50);
}

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if Statement - Overview

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Purpose

The purpose of the if statement is to make decisions, and execute different parts of your program depending on a true/false value.

General Forms

The if statement has this form:

do these statements
if (condition) {
    do this clause if the condition is true
}
do these statements afterwards

or

do these statements
if (condition) {
    do this clause if the condition is true
} else {
    do this clause if the condition is false
}
do these statements afterwards

It is good programming style to always write the curly braces, {}, altho they are not needed if the clause contains only a single statement.

Condition is true or false

The value of condition must be true or false (ie, a boolean value). It is often a comparison.

. . .
if (marks < 60) {
    JOptionPane.showMessageDialog(null, "This is terrible");
} else {
    JOptionPane.showMessageDialog(null, "Not so bad");
}
. . .

The code above will display one of two dialogs, depending on teh value of marks.

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