ManagedSet.java

package org.theonefx.wcframework.ioc.val;

import java.util.LinkedHashSet;
import java.util.Set;

import org.theonefx.wcframework.ioc.BeanMetadataElement;


/**
 * Tag collection class used to hold managed Set values, which may
 * include runtime bean references (to be resolved into bean objects).
 */
public class ManagedSet<E> extends LinkedHashSet<E> implements Mergeable, BeanMetadataElement {

	private static final long serialVersionUID = -7769969043795921702L;

	private Object source;

	private String elementTypeName;

	private boolean mergeEnabled;


	public ManagedSet() {
	}

	public ManagedSet(int initialCapacity) {
		super(initialCapacity);
	}


	/**
	 * Set the configuration source <code>Object</code> for this metadata element.
	 * <p>The exact type of the object will depend on the configuration mechanism used.
	 */
	public void setSource(Object source) {
		this.source = source;
	}

	public Object getSource() {
		return this.source;
	}

	/**
	 * Set the default element type name (class name) to be used for this set.
	 */
	public void setElementTypeName(String elementTypeName) {
		this.elementTypeName = elementTypeName;
	}

	/**
	 * Return the default element type name (class name) to be used for this set.
	 */
	public String getElementTypeName() {
		return this.elementTypeName;
	}

	/**
	 * Set whether merging should be enabled for this collection,
	 * in case of a 'parent' collection value being present.
	 */
	public void setMergeEnabled(boolean mergeEnabled) {
		this.mergeEnabled = mergeEnabled;
	}

	public boolean isMergeEnabled() {
		return this.mergeEnabled;
	}

	@SuppressWarnings("unchecked")
	public Set<E> merge(Object parent) {
		if (!this.mergeEnabled) {
			throw new IllegalStateException("Not allowed to merge when the 'mergeEnabled' property is set to 'false'");
		}
		if (parent == null) {
			return this;
		}
		if (!(parent instanceof Set)) {
			throw new IllegalArgumentException("Cannot merge with object of type [" + parent.getClass() + "]");
		}
		Set<E> merged = new ManagedSet<E>();
		merged.addAll((Set<E>) parent);
		merged.addAll(this);
		return merged;
	}

}