Question

true or false give reason language in java

1.A static inner class can access the instance variables and methods of its outer non-static class
2.executeQuery from statement may return more than one resultset object
3.Connection is java.sql interface that establishes a session with a specific database
4.Writable is an interface in Hadoop that acts as a wrapper class to almost all the primitive data type
5.Text is the wrapper class of string in Hadoop

Answer 1

Following is the answer:

1.A static inner class can access the instance variables and methods of its outer non-static class
False
Any non-static nested class is known as inner class in java. Java inner class is associated with the object of the class and they can access all the variables and methods of the outer class. Since inner classes are associated with the instance, we can't have any static variables in them.

2.executeQuery from statement may return more than one resultset object
True

3.Connection is java.sql interface that establishes a session with a specific database
True

4.Writable is an interface in Hadoop that acts as a wrapper class to almost all the primitive data type
True

5.Text is the wrapper class of string in Hadoop
True
Writable is an interface in Hadoop. Writable in Hadoop acts as a wrapper class to almost all the primitive data type of Java. That is how int of java has become IntWritable in Hadoop and String of Java has become Text in Hadoop.