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Cli clip = getClipFromSomewhere();

// Get the gain control from clip

FloatControl gainControl = (FloatControl) clip.getControl(FloatControl.Type.MASTER_GAIN);

// set the gain (between 0.0 and 1.0)

double gain = 0.25;
float dB = (float) (Math.log(gain) / Math.log(10.0) * 20.0);
gainControl.setValue(dB);

written by objects \\ tags: audio, Clip, Player, sound, volume

Java introduced scripting support with Java 6.

Heres a simple example showing how to use the JavaScript scripting engine to evaluate an expression.

ScriptEngineManager manager = new ScriptEngineManager();
ScriptEngine engine = manager.getEngineByName("JavaScript");
Object result = engine.eval("6 * (3 + 5)");

written by objects \\ tags: evaluate, expression, javascript, script, scripting

We often get students struggling to read and validate console input from the user. The following example gives a simple example of an approach that can be used.

It reads the input from the user and checks if it is a valid double. If its not it prompts the user again. Could easily be modified for different validation that you may require.

  Scanner input = new Scanner( System.in );
  Double value = null;
  while (value==null) {
	  System.out.print("Please enter number: ");
	  String s = input.nextLine();
	  if (s.length()==0) {
		  System.out.println("You did not enter a value; Try again");
	  } else {
		  try {
			  value = new Double(s);
		  } catch (Exception ex) {
			  System.out.println("You did not enter a valid value; Try again");
		  }
	  }
  }
  double d = value.doubleValue();

written by objects \\ tags: console, input, prompt, stdin, validate