Essential Books

Object casting

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As with primitives, objects can be cast both explicitly and implicitly.

Implicit casting happens when the source type extends or implements the target type (casting to a superclass or interface).

Explicit casting has to be done when the source type is extended or implemented by the target type (casting to a subtype). This can produce a runtime exception (ClassCastException) when the object being cast is not of the target type (or the target’s subtype). 

Float floatVar = new Float(42.0f);
Number n = floatVar;                //Implicit (Float implements Number)
Float floatVar2 = (Float) n;        //Explicit
Double doubleVar = (Double) n;      //Throws exception (the object is not Double)
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Type Conversion:
* Type Conversion
* Numeric primitive casting
* Basic Numeric Promotion
* Non-numeric primitive casting
* Object casting
* Testing if an object can be cast using instanceof
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0 Inheritance
1 Getting started with Java
2 Streams
3 Exceptions
4 Collections
5 Lambda Expressions
6 Generics
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24 Object Class Methods and Constructor
25 JAXB
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27 Networking
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35 Nashorn JavaScript engine
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60 RSA Encryption
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84 The Classpath
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91 Performance Tuning
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93 Common Pitfalls
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103 Just in Time JIT compiler
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118 Pitfalls - threads and concurrency
119 Splitting a string into fixed length parts
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123 super keyword
124 java.util.Objects class
125 Java command: java and javaw
126 Atomic types
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129 sun.misc.Unsafe
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148 Java Editions, versions, releases and distributions
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152 Generating Java Code
153 JShell
154 Benchmarks
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156 Multi-release JAR files
157 Stack-Walking API
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159 Sockets
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161 Using other scripting languages in Java
162 Functional interfaces
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164 2D graphics
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169 Local Inner class
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171 Immutable class
172 String Tokenizer
173 File upload to S3 / AWS
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176 Enum starting with a number
177 SortedMap
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180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors