Bug 138562 Splite extendsexcpetion to seperate sub class
The suggestion is Parent invalid Cycle extends Different type extends Not top level extends
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/core/DesignElement.java
assert prop != null;
		setProperty( prop, value );
	}
	/**
	 * Sets the value of a property. The value must have already been validated,
	 * and must be of the correct type for the property. The property must be
	 * valid for this object. The property can be a system or user-defined
	 * property. The value is set locally. If the value is null, then the
	 * property is "unset."
	 * <p>
	 * Part of: Property value system.
	 * 
	 * @param prop
	 *            The property definition. Must be valid. Can be a
	 *            system-defined or user-defined property.
	 * @param value
	 *            The value to set. Must be valid for the property.
	 */
	public void setProperty( ElementPropertyDefn prop, Object value )
	{
		assert prop != null;
		String propName = prop.getName( );
		
		
		if ( prop.isIntrinsic( ) )
		{
			setIntrinsicProperty( propName, value );
			return;
		}