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Q) Give list of some important classes of long package?




A)
1) Wrapper classes:

Integer
Short
Byte
Long
Float
Double
Boolean
Character

To each primitive are library class is given.
Because of this, primitive data types only java is not 100% object oriented language.
Each primitive can be converted to object. Just we cover this by using classes.


2) String
3) StringBuffer
4) StringBuilder
5) System->os services are encapsulated in system classes
6) Exception classes

->date.class file-->in sql package
->date.class file-->in long package

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