All methods in an abstract class must be declared abstract

A catch can have comma separated multiple arguments

The overriding method cant have a more restrictive access modifier than the method being overridden.

The method which is marked as final can be overridden.

The method which is marked as static can not be overridden.

The access level for overriding method can be less restrictive than the overridden method.

Overriding method can change the return type regardless of overridden method.

Argument List of overriding method can be different

Constructor can be overloaded

If method is not inherited then it is not possible to override it

Contrustor can have any return type

Reference variables are immutable while String objects are not

equal() method is used to compare the primitive variables

Below expression is valid While(int x==2)

The only type that a switch can evaluate is the primitive int

For any reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true

Collection and Collections refer to same type of interface

The + operator in JAVA can't be overloaded.

Relational operators always result in a integer value.

Java has six relational operators in that two are also called as equality operators.