egovframework.rte.fdl.excel.util.AbstractPOIExcelView.java Source code

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Here is the source code for egovframework.rte.fdl.excel.util.AbstractPOIExcelView.java

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/*
 * Copyright 2008-2009 MOPAS(Ministry of Public Administration and Security).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 *  : https://jira.springsource.org/browse/SPR-6898?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 */

package egovframework.rte.fdl.excel.util;

import java.util.Map;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.springframework.web.servlet.view.AbstractView;

/**
 * AbstractExcelView support for XSSFWorkbook (xmlx format; POI 3.5+)
 * <p>
 * <b>NOTE:</b>      ? ? ??.
 * @author  ?
 * @since 2013.05.22
 * @version 1.0
 * @see <pre>
 *  == ?(Modification Information) ==
 *   
 *   ?         ?           
 *  ------------   --------    ---------------------------
 *   2013.05.22      ?            ?
 * 
 * </pre>
 */

public abstract class AbstractPOIExcelView extends AbstractView {

    /** The content type for an Excel response */
    //    private static final String CONTENT_TYPE_XLSX = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
    //    private static final String CONTENT_TYPE_XLS = "application/vnd.ms-excel";

    /**
     * Default Constructor. Sets the content type of the view for excel files.
     */
    public AbstractPOIExcelView() {
    }

    @Override
    protected boolean generatesDownloadContent() {
        return true;
    }

    /**
     * Renders the Excel view, given the specified model.
     */
    @Override
    protected final void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request,
            HttpServletResponse response) throws Exception {

        XSSFWorkbook workbook = new XSSFWorkbook();
        logger.debug("Created Excel Workbook from scratch");

        /*if (workbook instanceof XSSFWorkbook) {
        setContentType(CONTENT_TYPE_XLSX);
        } else {
        setContentType(CONTENT_TYPE_XLS);
        }*/
        setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");

        buildExcelDocument(model, workbook, request, response);

        // Set the content type.
        response.setContentType(getContentType());

        // Flush byte array to servlet output stream.
        ServletOutputStream out = response.getOutputStream();
        out.flush();
        workbook.write(out);
        out.flush();

        // Don't close the stream - we didn't open it, so let the container
        // handle it.
        // http://stackoverflow.com/questions/1829784/should-i-close-the-servlet-outputstream
    }

    /**
     * Subclasses must implement this method to create an Excel Workbook.
     * HSSFWorkbook and XSSFWorkbook are both possible formats.
     */
    //    protected abstract Workbook createWorkbook();

    /**
      * Subclasses must implement this method to create an Excel HSSFWorkbook
      * document, given the model.
      * 
      * @param model
      *            the model Map
      * @param workbook
      *            the Excel workbook to complete
      * @param request
      *            in case we need locale etc. Shouldn't look at attributes.
      * @param response
      *            in case we need to set cookies. Shouldn't write to it.
      */
    protected abstract void buildExcelDocument(Map<String, Object> model, XSSFWorkbook workbook,
            HttpServletRequest request, HttpServletResponse response) throws Exception;

    /**
    * Convenient method to obtain the cell in the given sheet, row and column.
    * <p>Creates the row and the cell if they still doesn't already exist.
    * Thus, the column can be passed as an int, the method making the needed downcasts.
    * @param sheet a sheet object. The first sheet is usually obtained by workbook.getSheetAt(0)
    * @param row thr row number
    * @param col the column number
    * @return the XSSFCell
    */
    protected XSSFCell getCell(XSSFSheet sheet, int row, int col) {
        XSSFRow sheetRow = sheet.getRow(row);
        if (sheetRow == null) {
            sheetRow = sheet.createRow(row);
        }
        XSSFCell cell = sheetRow.getCell((short) col);
        if (cell == null) {
            cell = sheetRow.createCell((short) col);
        }
        return cell;
    }

    /**
     * Convenient method to set a String as text content in a cell.
     * @param cell the cell in which the text must be put
     * @param text the text to put in the cell
     */
    protected void setText(XSSFCell cell, String text) {
        cell.setCellType(XSSFCell.CELL_TYPE_STRING);
        cell.setCellValue(text);
    }

}