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The Null literal

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The Null literal (written as null) represents the one and only value of the null type. Here are some examples 

MyClass object = null;
MyClass[] objects = new MyClass[]{new MyClass(), null, new MyClass()};

myMethod(null);

if (objects != null) {
     // Do something
}

The null type is rather unusual. It has no name, so you cannot express it in Java source code. (And it has no runtime representation either.)

The sole purpose of the null type is to be the type of null. It is assignment compatible with all reference types, and can be type cast to any reference type. (In the latter case, the cast does not entail a runtime type check.)

Finally, null has the property that null instanceof <SomeReferenceType> will evaluate to false, no matter what the type is.

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Literals:
* Literals
* Using underscore to improve readability
* Hexadecimal Octal and Binary literals
* Boolean literals
* Escape sequences in literals
* Decimal Integer literals
* String literals
* The Null literal
* Floating-point literals
* Character literals
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0 Inheritance
1 Getting started with Java
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118 Pitfalls - threads and concurrency
119 Splitting a string into fixed length parts
120 Pitfalls - nulls and NullPointerException
121 SecurityManager
122 JNDI
123 super keyword
124 java.util.Objects class
125 Java command: java and javaw
126 Atomic types
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128 Converting to and from strings
129 sun.misc.Unsafe
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176 Enum starting with a number
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180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors