ManagedProperties.java

package org.theonefx.wcframework.ioc.val;

import java.util.Properties;

import org.theonefx.wcframework.ioc.BeanMetadataElement;


/**
 * Tag class which represents a Spring-managed {@link Properties} instance
 * that supports merging of parent/child definitions.
 */
public class ManagedProperties extends Properties implements Mergeable, BeanMetadataElement {

	private static final long serialVersionUID = -3463760525645386676L;

	private Object source;

	private boolean mergeEnabled;


	/**
	 * 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 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;
	}


	public Object 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 Properties)) {
			throw new IllegalArgumentException("Cannot merge with object of type [" + parent.getClass() + "]");
		}
		Properties merged = new ManagedProperties();
		merged.putAll((Properties) parent);
		merged.putAll(this);
		return merged;
	}

}