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copied!<p>Since enums <em>are</em> classes and thus <em>can</em> implement interfaces, you could create an interface which holds your contains() method and then implement that method on your enums, then use a generic method which takes a class token of a specific enum type implementing that interface (and which could be set at runtime) to test. Something like this:</p> <p><strong>CanBeTestedForContains:</strong></p> <pre><code>public interface CanBeTestedForContains { boolean contains(String name); } </code></pre> <p><strong>ColorEnum:</strong></p> <pre><code>import java.util.HashSet; import java.util.Set; public enum ColorEnum implements CanBeTestedForContains { R("red"), B("blue"); private static Set<String> names = new HashSet<String>(3) { { for (final ColorEnum e : ColorEnum.values()) { add(e.name); } } }; private String name; private ColorEnum(final String name) { this.name = name; } @Override public boolean contains(final String name) { return names.contains(name); } } </code></pre> <p><strong>SuitEnum:</strong></p> <pre><code>import java.util.HashSet; import java.util.Set; public enum SuitEnum implements CanBeTestedForContains { D("diamonds"), H("hearts"), C("clubs"), S("spades"); private static Set<String> names = new HashSet<String>(3) { { for (final SuitEnum e : SuitEnum.values()) { add(e.name); } } }; private String name; private SuitEnum(final String name) { this.name = name; } @Override public boolean contains(final String name) { return names.contains(name); } } </code></pre> <p><strong>ContainsSelectorTest:</strong></p> <pre><code>public class ContainsSelectorTest { private static <E extends Enum<E> & CanBeTestedForContains> boolean contains(final Class<E> enumClass, final String name) { return enumClass.getEnumConstants()[0].contains(name); } public static void main(final String[] args) { if (contains(ColorEnum.class, "red")) { System.out.printf("%s contains %s\n", ColorEnum.class, "red"); } if (contains(SuitEnum.class, "hearts")) { System.out.printf("%s contains %s\n", SuitEnum.class, "hearts"); } if (contains(SuitEnum.class, "red")) { System.out.println("This shouldn't happen."); } else { System.out.printf("%s DOES NOT contain %s\n", SuitEnum.class, "red"); } } } </code></pre> <p><strong>Output:</strong></p> <blockquote> <p>class ColorEnum contains red</p> <p>class SuitEnum contains hearts class</p> <p>class SuitEnum DOES NOT contain red</p> </blockquote>

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