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POEnums shared static look-up method
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  1. POEnums shared static look-up method
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    copied!<p>I have the following Enum:</p> <pre><code>public enum MyEnum{ A(10, "First"), // B(20, "Second"), // C(35, "Other options"); private Integer code; private String description; private MyEnum(Integer code, String description) { this.code = code; this.description = description; } public Integer getCode() { return code; } public String getDescription() { return description; } public static MyEnum getValueOf(Integer code) { for (MyEnum e : MyEnum.values()) { if (e.getCode().equals(code)) { return e; } } throw new IllegalArgumentException("No enum const " + MyEnum.class.getName() + " for code \'" + code + "\'"); } } </code></pre> <p>Which works fine. The <code>getValueOf</code>-method exists because when communicating with an external partner, we only get the code (they chose) to map to. I need the description because I need to show a meaningfull phrase in the GUI.</p> <p>But I now have a number of similar enum classes. All having their own code &amp; description, and they need the same lookup functionality. I wanted the <code>getValueOf</code>-method to be generic so I don't need to support 30+ different enums for basically the same method.</p> <p>To solve this I wanted to make an abstract class to define this method and implement some of the common logic but this is impossible because I can't extend <code>Enum</code>.</p> <p>Then I tried to make a Utility class with the following method:</p> <pre><code>public static &lt;T extends Enum&lt;T&gt;&gt; T getValueOf(Enum&lt;T&gt; type, Integer code) {...} </code></pre> <p>But generics with Enums are confusing and I don't understand how to get this working.</p> <p>Basically what I want to know is: What is a good approach to define a common utility to an enum?</p>
 

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