Member Avatar for nazmule27

What is NULL?
Please answer if know it exactly in java Perspective.

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  • Latest Post Latest Post by JamesCherrill
Member Avatar for simrankim

Which Null you are looking for, in Java, in Sql, in C++.

Member Avatar for JamesCherrill

In Java you have variables and expressions that refer to objects or arrays.
"null" is the special value for those variables or expressions that have not been initialised to refer to a real object or array - it means that they refer to nothing.
eg
String s; declares a variable that refers to a String, but it has not been initialised, so its value is null

Member Avatar for jalpesh_007

Also you can define null value with String s =""; //declares a variable refers to String class,having initialised with null string..so its value is null..

You can also define like Strinf s1 = NULL; //It's also java's reserved keyword..

Member Avatar for JamesCherrill

Also you can define null value with String s =""; //declares a variable refers to String class,having initialised with null string..so its value is null..

You can also define like Strinf s1 = NULL; //It's also java's reserved keyword..

Wrong, wrong, wrong.

"" is a String object containg a string of zero characters. The variable s refers to that object, it is NOT null.

Java is case sensitive, NULL is not the same as null

null is not a Java reserved keyword, it is a literal (J.L.S. 3.9)

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