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    <p>This will do what you want:</p> <pre><code>Map&lt;String,Integer&gt; map = new HashMap&lt;String, Integer&gt;(){{ put("cat", 2); put("dog", 1); put("llama", 0); put("iguana", -1); }}; </code></pre> <p>This statement creates an anonymous subclass of HashMap, where the only difference from the parent class is that the 4 entries are added during instance creation. It's a fairly common idiom in the Java world (although some find it controversial because it creates a new class definition).</p> <p>Because of this controversy, as of Java 9 there is a new idiom for conveniently constructing maps: the family of static <a href="https://docs.oracle.com/javase/9/docs/api/java/util/Map.html#of-K-V-" rel="nofollow noreferrer">Map.of methods</a>.</p> <p>With Java 9 or higher you can create the map you need as follows:</p> <pre><code>Map&lt;String, Integer&gt; map = Map.of( "cat", 2, "dog", 1, "llama", 0, "iguana", -1 ); </code></pre> <p>With larger maps, this <a href="https://docs.oracle.com/javase/9/docs/api/java/util/Map.html#ofEntries-java.util.Map.Entry...-" rel="nofollow noreferrer">alternative syntax</a> may be less error-prone:</p> <pre><code>Map&lt;String, Integer&gt; map = Map.ofEntries( Map.entry("cat", 2), Map.entry("dog", 1), Map.entry("llama", 0), Map.entry("iguana", -1) ); </code></pre> <p>(This is especially nice if Map.entry is statically imported instead of being referenced explicitly).</p> <p>Besides only working with Java 9+, these new approaches are not quite equivalent to the previous one:</p> <ul> <li>They don't allow you to specify what Map implementation is used</li> <li>They only create immutable maps</li> <li>They don't create an anonymous subclass of Map</li> </ul> <p>However, these differences shouldn't matter for many use cases, making this a good default approach for newer versions of Java.</p>
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    1. POC# to Java - Dictionaries?
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    1. USSean Reilly
    1. USSean Reilly
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    1. COIndeed it does. Thanks.
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      1. USWildBamaBoy
    2. COAnd here is an explanation on what this is doing. http://techpolesen.blogspot.com/2007/08/java-initializers-add-elements-to.html
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      1. USJosh Smeaton
    3. COHmmm... double braces syntax is not generally considered good style
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      1. USLuigi Plinge
 

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