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POWhy collection literals?
 

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    <p>From the various online articles on Java 7 I have come to know that Java 7 will be having collection literals<sup>1</sup> like the following:</p> <pre><code>List&lt;String&gt; fruits = [ "Apple", "Mango", "Guava" ]; Set&lt;String&gt; flowers = { "Rose", "Daisy", "Chrysanthemum" }; Map&lt;Integer, String&gt; hindiNums = { 1 : "Ek", 2 : "Do", 3 : "Teen" }; </code></pre> <p>My questions are:</p> <ol> <li>Wouldn't it have been possible to provide a static method <code>of</code> in all of the collection classes which could be used as follows:</li> </ol> <p><code>List&lt;String&gt; fruits = ArrayList.of("Apple", "Mango", "Guava");</code></p> <p>IMO this looks as good as the literal version and is also reasonably concise. Why then did they have to invent a new syntax (<strong>EDIT:</strong> By 'new' I mean 'new to Java'.)?</p> <ol start="2"> <li>When I say <code>List&lt;String&gt; fruits = [ "Apple", "Mango", "Guava" ];</code> what <code>List</code> would I actually get? Would it be <code>ArrayList</code> or <code>LinkedList</code> or something else?</li> </ol> <hr> <p><sup>1</sup> As noted in the comments, collection literals did <em>not</em> make the cut for Java 7, nor indeed Java 8. (Here's an <a href="http://mail.openjdk.java.net/pipermail/lambda-dev/2014-March/011938.html" rel="nofollow noreferrer">email</a> from Brian Goetz, an Oracle developer, summarizing the rationale for not including this feature; and here is the <a href="http://openjdk.java.net/jeps/186" rel="nofollow noreferrer">proposal</a> itself.)</p>
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    1. USWilli Mentzel
    1. USGreen Hyena
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    1. COWouldn't your first example have to be `List<String> fruits = ArrayList.of<String>("Apple", "Mango", "Guava");`? You'd need to specify the type somehow.
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      1. USPaul Tomblin
    2. COWith regards to your first question: how would you create maps in a similar way while keeping them type-safe?
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      1. USMichael Williamson
    3. CO@Paul: No, you can call generic methods without specifying the type. Java will infer it from the types of the arguments.
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      1. USsepp2k
 

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