StringBuffer abc = new StringBuffer("abc");
StringBuffer def = new StringBuffer("def");
boolean b1 = abc.equals(def);
boolean b2 = abc.toString().equals(def.toString());

String a = "Kamelle";
String b = "Kamele";
String c = "Kameleuter";

int v1 = a.compareTo(b);
int v2 = a.compareTo(c);
int v3 = b.compareTo(c);

System.out.println(v1);
System.out.println(v2);
System.out.println(v3);

System.out.println("Ä".compareTo("Z"));