RequiredClassPresent.java

package io.thorntail.condition.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Repeatable;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Annotation which may be placed upon a CDI component to conditionally veto it if a class is not present.
 *
 * <p>If the class mentioned in the annotation cannot be found, this component will be fully veto'd by the CDI container.</p>
 *
 * <p>This annotation may be used repeatedly and with {@link RequiredClassNotPresent} to create complex conditoions</p>
 *
 * <p>All condition annotations will be applied with implicit <b>AND</b> semantics.</p>
 *
 * <pre>
 * &#64;ApplicationScoped
 * &#64;RequiredClassPresent("org.something.WhichIsRequired")
 * public class MyComponent {
 *
 * }
 * </pre>
 *
 * @author Ken Finnigan
 * @author Bob McWhirter
 *
 * @see RequiredClassNotPresent
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ElementType.TYPE, ElementType.FIELD, ElementType.PARAMETER, ElementType.METHOD})
@Repeatable(RequiredClassPresent.List.class)
public @interface RequiredClassPresent {
    String value();

    @Retention(RetentionPolicy.RUNTIME)
    @Target({ElementType.TYPE, ElementType.FIELD, ElementType.PARAMETER, ElementType.METHOD})
    @interface List {
        RequiredClassPresent[] value();
    }
}