How to Check Null in Java

Checking Null in Java

1. 
   Use '=' to define a variable. A single '=' is used to declare a variable and assign a value to it. You can use this to set a variable to null.

   1. A value of '0' and null are not the same and will behave differently.
   2. variableName = null;
2. 
   Use '==' to check a variable's value. A '==' is used to check that the two values on either side are equal. If you set a variable to null with '=' then checking that the variable is equal to null would return true.

   1. variableName == null;
   2. You can also use '!=' to check that a value is NOT equal.
3. 
   Use an 'if' statement to create a condition for the null. The result of the expression will be a boolean (true or false) value. You can use the boolean value as a condition for what the statement does next.

   1. For example, if the value is null, then print text 'object is null'. If '==' does not find the variable to be null, then it will skip the condition or can take a different path.

Object object = null ; if ( object == null ) { System.out.print ( "object is null "); }