Java - Avoid multiple occurrence of some character in a String

The following is a Java method/function which avoids multiple occurrence (in a row) of some character in an input String. The parameters to the method (i.e., inputs) to the method/function include:

  1. input - The parent String under consideration
  2. character - The character of which multiple occurrence (in a row) should be avoided.
     
    public static String avoidMultipleOccurrence(String input, char character) {        
            if (input == null) {  
                return null;  
            }  
            if (input.length() == 0) {  
                return "";  
            }
            StringBuilder output = new StringBuilder();  
            output.append(input.charAt(0));        
            for (int idx = 1; idx < input.length(); idx++) {  
                if (Character.toString(input.charAt(idx)).equals(
                                                           "" + character)) {  
                    if(input.charAt(idx) != input.charAt(idx-1)) {  
                        output.append(input.charAt(idx));  
                    }  
                } else {  
                    output.append(input.charAt(idx));  
                }  
            }  
            return output.toString();  
    }

Sample Input: “theeee insaneeeee teeeeechieeeee”

Character selected: ‘e’

     
    public static void main(String[] args) {
            System.out.println(avoidMultipleOccurrence(
                    "theeee insaneeeee teeeeechieeeee", 'e'));
    }

Output: the insane techie