what is the difference between int and integer in java

1int is a primitive type. Variables of type int store the actual binary value for the integer you want to represent. int.parseInt("1") doesn't make sense because int is not a class and therefore doesn't have any methods.
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3Integer is a class, no different from any other in the Java language. Variables of type Integer store references to Integer objects, just as with any other reference (object) type. Integer.parseInt("1") is a call to the static method parseInt from class Integer (note that this method actually returns an int and not an Integer).
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5To be more specific, Integer is a class with a single field of type int. This class is used where you need an int to be treated like any other object, such as in generic types or situations where you need nullability.
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7Note that every primitive type in Java has an equivalent wrapper class:
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9    byte has Byte
10    short has Short
11    int has Integer
12    long has Long
13    boolean has Boolean
14    char has Character
15    float has Float
16    double has Double
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18Wrapper classes inherit from Object class, and primitive don't. So it can be used in collections with Object reference or with Generics.
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20Since java 5 we have autoboxing, and the conversion between primitive and wrapper class is done automatically. Beware, however, as this can introduce subtle bugs and performance problems; being explicit about conversions never hurts.
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1Int is a primitive data type
2On the other hand Integer is a wrapper class that wraps a primitive type
3int into an object
4Int provides less flexibility as compare to Integer as it only allows the
5binary value of an integer in it. The Intege on the other hand is more
6flexible in storing and manupulating in data since wrapper class inherit
7object class.