org.aksw.commons.accessors.PropertySource Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of aksw-commons-collections Show documentation

There is a newer version: 0.9.9

Show newest version

package org.aksw.commons.accessors;

import java.util.Collection;

/**
 * This class is similar to the spring PropertySource - except that it allows setting properties as well.
 * A simple interface to resolve properties by name, value type and value multiplicity (single or multi).
 * 
 * 
 * 
 * @author raven Apr 10, 2018
 *
 */
public interface PropertySource {
	Object getSource();
	
	 SingleValuedAccessor getProperty(String name, Class valueType);
	
	
	/**
	 * Retrieve an accessor to a multi valued collection
	 * 
	 * @param name
	 * @param itemType
	 * @return
	 */
	default  SingleValuedAccessor> getCollectionProperty(String name, Class itemType) {
		Object tmp = getProperty(name, Collection.class);
		return (SingleValuedAccessor>) tmp;
	}
	

	/**
	 * Retrieves a single valued property and wraps it as a set with at most 1 item.
	 * Removing the item from the set is equivalent to setting the property to null.
	 * 
	 * @param name
	 * @param itemType
	 * @return
	 */
//	default  SingleValuedAccessor> getPropertyAsSet(String name, Class itemType) {
//		SingleValuedAccessor> result =
//				new SingleValuedAccessorDirect<>(
//						new CollectionFromSingleValuedAccessor<>(
//								getProperty(name, itemType)));
//		return result;
//	}
	default  CollectionAccessor getPropertyAsSet(String name, Class itemType) {
		SingleValuedAccessor accessor = getProperty(name, itemType);
		if(accessor == null) {
			throw new RuntimeException("No accessor for " + name + " on " + this);
		}
		CollectionAccessor result =
						new CollectionAccessorFromSingleValuedAccessor<>(accessor);
		return result;
	}

}