Bug 119331 Library - name space terminology and behavior
During BIRT 2.0 library feature review meeting the following change was decided. - Change the term namespace to 'prefix' - By default use the library name as the prefix ( namespace ); the dialog to input prefix should be prompted only if hte auto generated prefix is not unique.
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DNDUtil.java
}
		container = unwrapToModel( container );
		if ( container instanceof DesignElementHandle )
		{
			( (DesignElementHandle) container ).addElement( handle,
					DEUtil.getDefaultSlotID( container ) );
		}
		else if ( container instanceof SlotHandle )
		{
			( (SlotHandle) container ).add( handle );
		}
	}
	/**
	 * Validates target elements can contain transfer data
	 * 
	 * @param targetObj
	 *            target elements
	 * @param transferData
	 *            transfer data,single object or array are permitted
	 * @return if target elements can be dropped
	 */
	public static boolean handleValidateTargetCanContain( Object targetObj,
			Object transferData )
	{
		return handleValidateTargetCanContain( targetObj, transferData, true ) != CONTAIN_NO;
	}
	/**
	 * Validates target elements can contain transfer data.
	 * <p>
	 * If transfer data is single element, validate target's container also