About Java
What is java
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what is thread in java
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PDF & Excel
how to generate pdf in java using itext
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create excel file using java
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Create File
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Read Multiple Files
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Externalization Example
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Java 8
Lambda Expression
Lambda Expression example
Construct Lambda
Default Methods in interface
@FunctionalInterface Annotation
Functional Interface
Static Method in interface
Removed Per Gen
HashMap Changes
Java 9
Private Methods in Interface
Immutable Collections
Try with resource

what is wrapper class in java

what is wrapper class in java

A wrapper class is use to hold  a primitive data type like Integer is a wrapper class which holds the reference of int built in data type.

If we want to convert from primitive data type to corresponding object type , and to convert data from object type to the respective primitive data type then we have to through the predefined classes called wrapper classes.

java has provided all the wrapper classes with respect to the primitive data type in java.lang package.

The valueOf() and typeValue() method is available in all wrapper classes except Character

list of wrapper classes in java

Primitive data type Respective wrapper classes
byte java.lang.Byte
int java.lang.Integer
char java.lang.Character
float java.lang.Float
double java.lang.Double
short java.lang.Short
boolean java.lang.Boolean
long java.lang.Long

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