java-not empty java-not-empty java not empty() java-null

java-null
java-not(empty()) , string not empty, java-string-not-empty
java-string-not-empty

java-not-null

if (request.getParameter("config0") !=null )configFile0=request.getParameter("config0");

if (i==0 && ! keyValue.equals("null") && (! KEYVALUE1.trim().equals("")))

if (! keyValue.equals("null"))configFile0=request.getParameter("config0");