Essential Books

Basic Usage - Creating a ByteBuffer

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There’s two ways to create a ByteBuffer, where one can be subdivided again.

If you have an already existing byte[], you can “wrap” it into a ByteBuffer to simplify processing: 

byte[] reqBuffer = new byte[BUFFER_SIZE];
int readBytes = socketInputStream.read(reqBuffer);
final ByteBuffer reqBufferWrapper = ByteBuffer.wrap(reqBuffer);

This would be a possibility for code that handles low-level networking interactions

If you do not have an already existing byte[], you can create a ByteBuffer over an array that’s specifically allocated for the buffer like this: 

final ByteBuffer respBuffer = ByteBuffer.allocate(RESPONSE_BUFFER_SIZE);
putResponseData(respBuffer);
socketOutputStream.write(respBuffer.array());

If the code-path is extremely performance critical and you need direct system memory access, the ByteBuffer can even allocate direct buffers using #allocateDirect()

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ByteBuffer:
* ByteBuffer
* Basic Usage - Creating a ByteBuffer
* Basic Usage - Using DirectByteBuffer
* Basic Usage - Write Data to the Buffer
Table Of Contents
0 Inheritance
1 Getting started with Java
2 Streams
3 Exceptions
4 Collections
5 Lambda Expressions
6 Generics
7 File I/O
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15 Basic Control structures
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17 Console I/O
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20 Regular Expressions
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25 JAXB
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27 Networking
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35 Nashorn JavaScript engine
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37 Remote Method Invocation (RMI)
38 Iterator and Iterable
39 Operators
40 Asserting
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42 Properties Class
43 Preferences
44 Reflection API
45 Constructors
46 ByteBuffer
47 Serialization
48 JSON in Java
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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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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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129 sun.misc.Unsafe
130 Java Memory Model
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137 Java Virtual Machine JVM
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142 Java SE 8 Features
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147 Using ThreadPoolExecutor in multi-threaded applications
148 Java Editions, versions, releases and distributions
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152 Generating Java Code
153 JShell
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156 Multi-release JAR files
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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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167 Enum Map
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169 Local Inner class
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171 Immutable class
172 String Tokenizer
173 File upload to S3 / AWS
174 Readers and writers
175 Hashtable
176 Enum starting with a number
177 SortedMap
178 WeakHashMap
179 LinkedHashMap
180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors