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Annotation binding library

There is a newer version: 3.2.0

package io.github.sporklibrary.reflection;

import io.github.sporklibrary.exceptions.BindException;

import java.lang.annotation.Annotation;
import java.lang.reflect.Field;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

/**
 * A utility  class for {@link AnnotatedField}.
 */
public final class AnnotatedFields
{
	private AnnotatedFields()
	{
	}

	/**
	 * Get an immutable set of annotated fields from the provided class
	 * @param annotationClass the annotation class
	 * @param annotatedClass the class to search for annotations
	 * @param  the annotationClass type
	 * @return a set of AnnotatedField objects for the specified annotation type
	 */
	public static  Set> get(Class annotationClass, Class annotatedClass)
	{
		HashSet> annotatedFieldSet = new HashSet<>();

		for (Field field : annotatedClass.getDeclaredFields())
		{
			AnnotationType annotation = field.getAnnotation(annotationClass);

			if (annotation != null)
			{
				annotatedFieldSet.add(new AnnotatedField<>(annotation, field));
			}
		}

		return !annotatedFieldSet.isEmpty() ? annotatedFieldSet : Collections.>emptySet();
	}

	/**
	 * Set a value for an AnnotatedField on an object
	 * @param annotatedField the AnnotatedField
	 * @param parentObject the parent object
	 * @param valueObject the field value to bind
	 */
	public static void setValue(AnnotatedField annotatedField, Object parentObject, Object valueObject)
	{
		Field field = annotatedField.getField();

		boolean accessible = field.isAccessible();

		try
		{
			if (accessible)
			{
				field.set(parentObject, valueObject);
			}
			else
			{
				field.setAccessible(true);
				field.set(parentObject, valueObject);
				field.setAccessible(false);
			}
		}
		catch (IllegalAccessException e)
		{
			throw new BindException(annotatedField.getAnnotation().getClass(), parentObject.getClass(), field, "field not accessible", e);
		}
		finally
		{
			// ensure the Field isn't accessible when it shouldn't be
			if (!accessible && field.isAccessible())
			{
				field.setAccessible(false);
			}
		}
	}
}