Essential Books

Using the raw iterator

suggest change

While using the foreach loop (or “extended for loop”) is simple, it’s sometimes beneficial to use the iterator directly. For example, if you want to output a bunch of comma-separated values, but don’t want the last item to have a comma: 

List<String> yourData = //...
Iterator<String> iterator = yourData.iterator();
while (iterator.hasNext()){
    // next() "moves" the iterator to the next entry and returns it's value.
    String entry = iterator.next();
    System.out.print(entry);
    if (iterator.hasNext()){
        // If the iterator has another element after the current one:
        System.out.print(",");
    }
}

This is much easier and clearer than having a isLastEntry variable or doing calculations with the loop index.

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Iterator and Iterable:
* Iterator and Iterable
* Creating your own Iterable.
* Removing elements using an iterator
* Using Iterable in for loop
* Using the raw iterator
Table Of Contents
0 Inheritance
1 Getting started with Java
2 Streams
3 Exceptions
4 Collections
5 Lambda Expressions
6 Generics
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35 Nashorn JavaScript engine
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38 Iterator and Iterable
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84 The Classpath
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91 Performance Tuning
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103 Just in Time JIT compiler
104 FTP File Transfer Protocol
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118 Pitfalls - threads and concurrency
119 Splitting a string into fixed length parts
120 Pitfalls - nulls and NullPointerException
121 SecurityManager
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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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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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161 Using other scripting languages in Java
162 Functional interfaces
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164 2D graphics
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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
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180 StringBuffer
181 Choosing Collections
182 C++ Comparison
183 CompletableFuture
184 Contributors