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Break a string up into substrings all of a known length

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The trick is to use a look-behind with the regex \G, which means “end of previous match”: 

String[] parts = str.split("(?<=\\G.{8})");

The regex matches 8 characters after the end of the last match. Since in this case the match is zero-width, we could more simply say “8 characters after the last match”.

Conveniently, \G is initialized to start of input, so it works for the first part of the input too.

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Splitting a string into fixed length parts:
* Splitting a string into fixed length parts
* Break a string up into substrings all of a known length
* Break a string up into substrings all of variable length
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0 Inheritance
1 Getting started with Java
2 Streams
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91 Performance Tuning
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103 Just in Time JIT compiler
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112 Pitfalss - performance
113 Creating Images Programmatically
114 Applets
115 NIO Networking
116 New File I/O
117 Secure objects
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
130 Java Memory Model
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148 Java Editions, versions, releases and distributions
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152 Generating Java Code
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161 Using other scripting languages in Java
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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