Java: String - add character n-times [duplicate]

Answer 1

for(int i = 0; i < n; i++) {
    existing_string += 'c';
}

but you should use StringBuilder instead, and save memory

int n = 3;
String existing_string = "string";
StringBuilder builder = new StringBuilder(existing_string);
for (int i = 0; i < n; i++) {
    builder.append(" append ");
}

System.out.println(builder.toString());