Suma Soft interview question

Java ==== explain your project. what is JVM ? what is JRE ? what is JDK ? difference between method overloading and method overriding ? difference between String literal and String object ? Difference between comaparable and comparator ? Difference between hashmap and hashtable ? what is SCP ?(String constant pool) declear HashMap. what is output follwoing code ? String s= new String("Shrishail"); String s1= new String("Shrishail"); System.out.println(s==s1); // flase - because in string assignment operator is check address location not contains. String s="Shrishail"; String s1="Shrishail"; System.out.println(s==s1); // true write one program using Comparator ? write one code String input ="Shrishail is my name"; Output = name my is Shrishail Adavance java ============= steup for jdbc what resultset ? difference between statement and Preparedstatement which one better statement or PreparedStatement. what is Statement ? what is PreparedStatement ? Sql === write query employee table where department is Developing write query for second maximum salary; what are type of aggregate function.