public class VariableInRegex {

    public static void main(String[] args) {
        String jb = "Javabeginners, Quelltexte und Snippets f\u00fcr Java-Anf\u00e4nger.";
        String var = "Snippets";
        if(jb.matches(".*" + var + ".*")) {
            jb = jb.replaceAll(var, "Kaffee");
            System.out.println(jb);
        }
    }
}