Whether String Str1 will refer string poll for Str1 exists in the pool or not. If exists, then this will return the reference, If not exist, will it create new object like new operator ?
String str2 never refer the string pool because it is created by new operator(creates new String object in the heap). Which one is memory efficient ?
Obviously the first statement is more memory efficient. Both use the same String from the String pool, but the first one uses only this object; the second one makes an exact copy of it and uses that. With String being immutable, that's completely superfluous. That's why the API discourages using that constructor, as Campbell's link indicates.