DRY Code

DRY stands for Don't Repeat Yourself and is a principal in computer science aimed at reducing repetition of information/code.

• the same chonk of code should not be repeated over and over again.
• if there is repetition in your code, the repeated code can most likely be put into a separate function that can the called where ever needed

Repeated Code Example 1:

public void example_one(){

  int[] array_a = {1,2,3,4,5,6,7,8,9}; 
  int sum_a = 0;
  int average_a = 0;
    
  for (int i = 0; i < array_a.length; i++){
    sum_a += array_a[i];
  }
  average_a = sum_a / array_a.length;

  int[] array_b = {2,4,6,8,10,12,14,16,18};  
  int sum_b = 0;
  int average_b = 0;
    
  for (int i = 0; i < array_a.length; i++){
    sum_b += array_b[i];
  }
  average_b = sum_b / array_b.length;  
}

Repeated Code Example 2:

public void exampleTwo(int amount, String type){
    
  double finalAmount = 0.0;
  String displayAmount = "";
    
  switch (type.toUpperCase()) {
    case "CEO":  
      finalAmount = (amount - (0.9 * amount)) - 0.99 * (amount - (0.9 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount); 
      break;
    case "MGR":  
      finalAmount = (amount - (0.4 * amount)) - 0.50 * (amount - (0.4 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    case "AMRG":  
      finalAmount = (amount - (0.4 * amount)) - 0.50 * (amount - (0.4 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    case "SE": 
      finalAmount = (amount - (0.2 * amount)) - 0.25 * (amount - (0.2 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    case "JE": 
      finalAmount = (amount - (0.2 * amount)) - 0.15 * (amount - (0.2 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    case "LC":  
      finalAmount = (amount - (0.1 * amount)) - 0.10 * (amount - (0.1 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    case "FF":  
      finalAmount = (amount - (0.1 * amount)) - 0.10 * (amount - (0.1 * amount));
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
    default: 
      finalAmount = amount;
      DecimalFormat df=new DecimalFormat("0.00");
      displayAmount = df.format(finalAmount);
      break;
  }
 }

DRY Code Solutions