Bug 167545 Copy a cascading parameter group and paste it to another parameter group causes an exception thrown
Steps to reproduce: 1.Copy a cascading parameter group using short cut key "Ctrl+x"/"Ctrl+c", or choosing context menu "Cut"/"Copy"; 2.Paste it to another parameter group using short cut key "Ctrl+v", or choosing context menu "Paste"; Expected result: The source one is pasted in the destination. Actual result: An exception thrown org.eclipse.birt.report.model.api.command.ContentException: The Cascading Parameter Group("Source") is not allowed in the slot (parameters) of Parameter Group("Destination").
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
for ( Iterator iterator = argumentInfoList.argumentsIterator( ); iterator.hasNext( ); i++ )
					{
						Object arg = iterator.next( );
						if ( argIndex == i )
						{
							return ( (IArgumentInfo) arg ).getType( );
						}
					}
				}
				return null;
			}
		}
		return null;
	}
	/**
	 * Get a DesignElementHandle's method's all arguments.
	 * 
	 * @param handle
	 * @param methodName
	 * @return Arguments map, key is argument name, value is argument type.
	 */
	public static Map getDesignElementMethodArguments(
			DesignElementHandle handle, String methodName )
	{
		List methods = handle.getDefn( ).getMethods( );