SlingModelEnumValueMapInjector

SlingModelEnumValueMapInkjector.java

/*
 * Copyright 2014 David Herges <david@spektrakel.de>
 * Licensed under MIT (http://opensource.org/licenses/MIT)
 */
 
 package org.apache.sling.models.extensions.injector;

import org.apache.felix.scr.annotations.Component;
import org.apache.felix.scr.annotations.Property;
import org.apache.felix.scr.annotations.Service;
import org.apache.sling.api.adapter.Adaptable;
import org.apache.sling.api.resource.ValueMap;
import org.apache.sling.models.spi.DisposalCallbackRegistry;
import org.apache.sling.models.spi.Injector;
import org.osgi.framework.Constants;

import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Type;

@Component
@Service
@Property(name = Constants.SERVICE_RANKING, intValue = 9999)
public class SlingModelEnumValueMapInjector implements Injector {

    @Override
    public String getName() {
        return "enums";
    }

    @Override
    public Object getValue(Object adaptable, String name, Type declaredType, AnnotatedElement annotatedElement,
                           DisposalCallbackRegistry disposalCallbackRegistry) {

        // sanity check
        if (!(declaredType instanceof Class<?>)) {
            return null;
        }

        String value = getValueFor(adaptable, name);

        Class<?> cls = (Class<?>) declaredType;
        if (cls.isEnum()) {
            Enum[] enumConstants = (Enum[]) cls.getEnumConstants();
            for (Enum enumConstant : enumConstants) {
                if (enumConstant.name().equals(value)) {
                    return enumConstant;
                }
            }
        }

        return null;
    }

    private String getValueFor(Object adaptable, String name) {
        ValueMap map = null;

        if (adaptable instanceof ValueMap) {
            map = (ValueMap) adaptable;
        } else if (adaptable instanceof Adaptable) {
            map = ((Adaptable) adaptable).adaptTo(ValueMap.class);
        }

        return (map != null) ? map.get(name, String.class) : null;
    }
}