Instantiation Secrets for Java wrapper classes

Instantiation of wrapper classes
All the packaging classes are immutable.
Instantiation method:
Construction method
In addition to the character class, other packages


Integer (int x)
Integer (String x)
NumberFormatException exception


The parameters for the Boolean constructor method are not distinguished


Uppercase and lowercase


Two construction methods are provided for the installation class
static method: ValueOf () method
Integer i=integet.valueof (200);
Integer i=integet.valueof (200,8);
8 indicates the binary


The difference between the construction method and the valueof ()
The New keyword always creates an object
The ValueOf () method is cached in the 128 to 127


Number of integers (byte,short,int,long


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Instantiation Secrets for Java wrapper classes