1  
   2  // I put this block of text wherever I find problems with Strings
   3  // and StringBuffers to improve understanding of how each one works
   4  // and when to use one or the other.
   5  //
   6  // Rule #1: Use a StringBuffer if you intend to build a string out of
   7  // dynamic elements. That is, if you are going to include the results
   8  // of function calls or variables as part of the string then you use
   9  // a StringBuffer and do append() calls. StringBuffer's append is
  10  // much faster than using "+" to stick together String objects.
  11  //
  12  // Rule #2: But, if you are just building a string out of static pieces
  13  // of text, it's better to use Strings and "+" than creating a
  14  // StringBuffer and making append calls. Instead just use a String
  15  // and a bunch of "+" signs between the sections. For example:
  16  // String test = "this " + "is " + "a " + "test " + "string";
  17  // is _not_ expensive. Why? Because all the pieces are static text and
  18  // the compiler can make it into this _as it compiles the code_:
  19  // String test = "this is a test string";
  20  //
  21  // Rule #3: For goodness sake, do this:
  22  // StringBuffer test = new StringBuffer();
  23  // test.append("static string ");
  24  // test.append(dynamicCall());
  25  // test.append(" another static string ");
  26  // test.append(someVariable);
  27  // DON'T DO THIS:
  28  // StringBuffer test = new StringBuffer();
  29  // test.append("static string " + dynamicCall());
  30  // test.append(" another static string " + someVariable);
  31  // This is officially the worst of all worlds. You need to use a
  32  // StringBuffer in this case because you've got some dynamic parts
  33  // but there is still addition going on between dynamic parts (the
  34  // function call and variable) and static strings. Ack!
  35  //
  36  // If you can't remember anything else, remember this:
  37  // static strings = String and "+"
  38  // dynamic strings = StringBuffer and append()