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The int primitive

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A primitive data type such as int holds values directly into the variable that is using it, meanwhile a variable that was declared using Integer holds a reference to the value.

According to java API: “The Integer class wraps a value of the primitive type int in an object. An object of type Integer contains a single field whose type is int.”

By default, int is a 32-bit signed integer. It can store a minimum value of -231, and a maximum value of 231 - 1. 

int example = -42;
int myInt = 284;
int anotherInt = 73;

int addedInts = myInt + anotherInt; // 284 + 73 = 357
int subtractedInts = myInt - anotherInt; // 284 - 73 = 211

If you need to store a number outside of this range, long should be used instead. Exceeding the value range of int leads to an integer overflow, causing the value exceeding the range to be added to the opposite site of the range (positive becomes negative and vise versa). The value is ((value - MIN_VALUE) % RANGE) + MIN_VALUE, or ((value + 2147483648) % 4294967296) - 2147483648 

int demo = 2147483647; //maximum positive integer
System.out.println(demo); //prints 2147483647
demo = demo + 1; //leads to an integer overflow
System.out.println(demo); // prints -2147483648

The maximum and minimum values of int can be found at: 

int high = Integer.MAX_VALUE;    // high == 2147483647
int low = Integer.MIN_VALUE;     // low == -2147483648

The default value of an int is 0 

int defaultInt;    // defaultInt == 0
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Primitive Data Types:
* Primitive Data Types
* Comparing floating point values
* The char primitive
* Primitive Types Cheatsheet
* Using underscore to improve readability
* The float primitive
* Converting Primitives
* The int primitive
* Memory consumption of primitives vs. boxed primitives
* The double primitive
* The byte primitive
* The boolean primitive
* The long primitive
* Hexadecimal Octal and Binary literals
* Negative value representation
* The short primitive
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0 Inheritance
1 Getting started with Java
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121 SecurityManager
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124 java.util.Objects class
125 Java command: java and javaw
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180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors