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Difference between jar and Api ?


Difference between jar and Api ?
Api -Application programming interface.
= = = = = = = = = = = = = = = = = = = = = = =
Read this sentence slowly u will get idea
Api is nothing it is always partial who contain only interface or Abstract class. ..which I can't directly access. So to access that api in market several 3rd party vender r present.
Ex:-Apache,IBM etc..
Connection is an interface given by sun people for establish connection in jdbc Api. ..think can u directly access it ?
❌Connection con=
new Connection ();
U can't do this coz Connection is an interface so we can't instantiate it that's why we need implementation. ...For accessing that interface. .who will provide us implementation ?
Implementation provide by 3rd party vender so. ...that's why one vender provide us an Class DriverManager nd inside this class there is one Static Factory method i.e getConnection() when u call that static method with class name u will get to accessing connection
✔Connection con =DriverManager.getConnection();
Jar :-Java Archive. .
=========== = = = =
Jar is nothing we can say it contain bunch of class. ...
See. .Suppose sun people develop one class for purpose of Validation ...how can they provide this class. ...
1 . They can't give source code
2.They can't give .class file. .
Then how developer can use this validation Class who provide Business logic for Validate some Expressions or something. .
So they use one concept. They make that class as a jar file and provide us. When u need to use just add in ur class path u can easily access it

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