boolean previousExecPeriod = executionCourseView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal());
boolean previousExecPeriod = previousExecutionPeriod != null && executionCourseView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal());
    private void organizeExecutionCourseViews(HttpServletRequest request, List executionCourseViews,            InfoExecutionPeriod previousExecutionPeriod) {        Table executionCourseViewsTableCurrent1_2 	= new Table(2);              Table executionCourseViewsTableCurrent3_4 	= new Table(2);         Table executionCourseViewsTableCurrent5   	= new Table(1);         Table executionCourseViewsTablePrevious1_2 = new Table(2);        Table executionCourseViewsTablePrevious3_4 = new Table(2);        Table executionCourseViewsTablePrevious5 	= new Table(1);        for (Iterator iterator=executionCourseViews.iterator(); iterator.hasNext(); ) {        		ExecutionCourseView executionCourseView = (ExecutionCourseView) iterator.next();            		int curricularYear = executionCourseView.getCurricularYear().intValue();        		boolean previousExecPeriod = executionCourseView.getExecutionPeriodOID().equals(previousExecutionPeriod.getIdInternal());        		switch (curricularYear) {        			case 1:        			case 2:        				if (previousExecPeriod) {              				executionCourseViewsTablePrevious1_2.appendToColumn(curricularYear-1,executionCourseView);            			} else {            				executionCourseViewsTableCurrent1_2.appendToColumn(curricularYear-1,executionCourseView);            			}        				break;        			case 3:        			case 4:        				if (previousExecPeriod) {        					executionCourseViewsTablePrevious3_4.appendToColumn(curricularYear-3,executionCourseView);        				} else {        					executionCourseViewsTableCurrent3_4.appendToColumn(curricularYear-3,executionCourseView);        				}        				break;        			case 5:        				if (previousExecPeriod) {        					executionCourseViewsTablePrevious5.appendToColumn(curricularYear-5,executionCourseView);        				} else {        					executionCourseViewsTableCurrent5.appendToColumn(curricularYear-5,executionCourseView);        				}        				break;        		}        	}        				        request.setAttribute("executionCourseViewsTableCurrent1_2", executionCourseViewsTableCurrent1_2);        request.setAttribute("executionCourseViewsTableCurrent3_4", executionCourseViewsTableCurrent3_4);        request.setAttribute("executionCourseViewsTableCurrent5", executionCourseViewsTableCurrent5);                request.setAttribute("executionCourseViewsTablePrevious1_2", executionCourseViewsTablePrevious1_2);        request.setAttribute("executionCourseViewsTablePrevious3_4", executionCourseViewsTablePrevious3_4);        request.setAttribute("executionCourseViewsTablePrevious5", executionCourseViewsTablePrevious5);    }