aswi2020vldc-gitlab/src/main/java/vldc/aswi/utils/ExporterPDF.java @ 6af5c07d

package vldc.aswi.utils;

import com.lowagie.text.*;
import com.lowagie.text.Font;
import com.lowagie.text.alignment.HorizontalAlignment;
import com.lowagie.text.alignment.VerticalAlignment;
import com.lowagie.text.pdf.PdfWriter;
import vldc.aswi.model.table.contingencyTable.ContingencyTableRow;
import vldc.aswi.model.table.contingencyTable.ContingencyTableRowCell;

import java.io.File;
import java.io.FileOutputStream;
import java.util.List;

/**
 * Class used for exporting data to PDF files.
 */
public class ExporterPDF {

    /**
     * Exports data to .pdf file
     * @param tmpFile - Temporary file.
     * @param contingencyTableRows - Contingency table rows.
     */
    public static void export(File tmpFile, List<ContingencyTableRow> contingencyTableRows) {

        try {
            if (contingencyTableRows.size() == 0) {

                return;
            }

            // Create new document.
            Document doc = new Document();

            // Get instance of PdfWriter.
            PdfWriter.getInstance(doc, new FileOutputStream(tmpFile));

            // Create fonts.
            Font colRowFont = new Font(Font.HELVETICA, 14, Font.BOLD);
            Font dataFont = new Font(Font.HELVETICA, 12);

            // Calculate column and row count.
            int columnsCount = getColumnCount(contingencyTableRows.get(0));
            int rowsCount = contingencyTableRows.size();

            // Create table.
            Table table = new Table(columnsCount, rowsCount);

            for (ContingencyTableRow row : contingencyTableRows) {

                if (row.isHeader()) {
                    // Row is header.
                    setColRow(table, row.getCells(), colRowFont);
                } else {
                    // Row contains data.
                    setDataRow(table, row.getCells(), colRowFont, dataFont);
                }
            }

            // Open document and write created table into it.
            doc.open();
            doc.add(table);

            doc.close();
        } catch (Exception e) {

            System.out.println("PDF export failed.");
        }
    }

    /**
     * Set column header row.
     * @param table - Table.
     * @param cells - List of contingency table cells.
     * @param colRowFont - Column row styles.
     * @throws BadElementException If cell is not created successfully.
     */
    private static void setColRow(Table table, List<ContingencyTableRowCell> cells, Font colRowFont) throws BadElementException {

        for (ContingencyTableRowCell cell : cells) {

            // Create and prepare pdf cell.
            Cell pdfCell = prepareCell(cell.getValue(), colRowFont, cell.getColSpan());
            pdfCell.setHeader(true);
            table.addCell(pdfCell);
        }
    }

    /**
     * Set data row.
     * @param table - Table.
     * @param cells - List of contingency table cells.
     * @param colRowFont - Column row styles.
     * @param dataFont - Data row styles.
     * @throws BadElementException If cell is not created successfully.
     */
    private static void setDataRow(Table table, List<ContingencyTableRowCell> cells, Font colRowFont, Font dataFont) throws BadElementException {

        boolean headerWrited = false;

        for (ContingencyTableRowCell cell : cells) {

            // Create pdf cell.
            Cell pdfCell;

            // First cell is always header, so apply different style.
            if (!headerWrited) {

                headerWrited = true;

                // Prepare pdf cell.
                pdfCell = prepareCell(cell.getValue(), colRowFont, cell.getColSpan());
                pdfCell.setHeader(true);

            } else {

                // Prepare pdf cell.
                pdfCell = prepareCell(cell.getValue(), dataFont, cell.getColSpan());
            }

            table.addCell(pdfCell);
        }
    }

    /**
     * Prepare pdf cell.
     * @param value - Cell value.
     * @param font - Cell font.
     * @param colSpan - Cell colspan.
     * @return Prepared pdf cell.
     */
    private static Cell prepareCell(String value, Font font, int colSpan) {

        Cell cell = new Cell(new Phrase(value, font));
        cell.setColspan(colSpan);
        cell.setHorizontalAlignment(HorizontalAlignment.CENTER);
        cell.setVerticalAlignment(VerticalAlignment.CENTER);

        return cell;
    }

    /**
     * Calculate column count in contingency table row.
     * @param firstRow - First row of contingency table.
     * @return Column count in contingency table.
     */
    private static int getColumnCount(ContingencyTableRow firstRow) {

        int columnCount = 0;

        for (ContingencyTableRowCell cell : firstRow.getCells()) {

            columnCount += cell.getColSpan();
        }

        return columnCount;
    }
}