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+package javax.inject;
+
+import java.lang.annotation.Target;
+import java.lang.annotation.Retention;
+import java.lang.annotation.Documented;
+import static java.lang.annotation.RetentionPolicy.RUNTIME;
+import static java.lang.annotation.ElementType.ANNOTATION_TYPE;
+
+/**
+ * Identifies qualifier annotations. A qualifier annotates an injectable field
+ * or parameter and, combined with the type, identifies the implementation to
+ * inject. Qualifiers are optional and no more than one should annotate a
+ * single field or parameter. The qualifiers are bold in the following
+ * example:
+ *
+ * <pre>
+ * public class Car {
+ * &#064;Inject private <b>@Leather</b> Provider&lt;Seat> seatProvider;
+ *
+ * &#064;Inject void install(<b>@Tinted</b> Windshield windshield,
+ * <b>@Big</b> Trunk trunk) { ... }
+ * }</pre>
+ *
+ * <p>If one injectable method overrides another, the overriding method's
+ * parameters do not automatically inherit qualifiers from the overridden
+ * method's parameters.
+ *
+ * <p>Anyone can define a new qualifier. A qualifier annotation:
+ * <ul>
+ * <li>is annotated with {@code @Qualifier}, {@code @Retention(RUNTIME)},
+ * and typically {@code @Documented}.</li>
+ * <li>can have attributes.</li>
+ * <li>is <i>not</i> annotated with {@code @Target}. While this
+ * specification only covers applying qualifiers to fields and parameters,
+ * some injector configurations might use qualifier annotations in other
+ * places (on methods or classes for example).</li>
+ * <li>may be part of the public API, much like the dependency type, but
+ * unlike implementation types which needn't be part of the public
+ * API.</li>
+ * </ul>
+ *
+ * <p>For example:
+ *
+ * <pre>
+ * &#064;java.lang.annotation.Documented
+ * &#064;java.lang.annotation.Retention(RUNTIME)
+ * &#064;javax.inject.Qualifier
+ * public @interface Leather {
+ * Color color() default Color.TAN;
+ * public enum Color { RED, BLACK, TAN }
+ * }</pre>
+ *
+ * @see javax.inject.Named @Named
+ */
+@Target(ANNOTATION_TYPE)
+@Retention(RUNTIME)
+@Documented
+public @interface Qualifier {}