EDIT

/*

* Copyright  EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.remote.view;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStreamReader;

import java.util.Locale;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.IOUtils;

import org.springframework.web.servlet.View;

/**

 * This view will return a simple HTTP file download,

 * please specifiy content type, file name, suffix of

 * file name and the encoding of the file.

 *

 *

 * @author a.oppermann

 * @since 20.03.2014

 *

 */

public class FileDownloadView implements View{

    private String contentType;

    private String fileName;

    private String suffix;

    private String encoding;

    /**

     * This view will render a simple HTTP file download

     *

     * <p>

     *

     * Please make sure you set contentType, fileName, suffix and encoding via setter-methods.

     * Otherwise you'll run into an exception.

     */

    public FileDownloadView(){

      //empty constructor

    }

    /**

     * This view will render a simple HTTP file download with default

     * settings for content type (application/octet-stream) and encoding (no encoding).

     *

     * @param fileName specifiy the name of the file you want to save

     * @param suffix file ending like "txt" or "pdf"

     */

    public FileDownloadView(String fileName, String suffix){

        this.contentType = "application/octet-stream";

        this.fileName = fileName;

        this.suffix = suffix;

        this.encoding = null;

    }

    /**

     * This view will render a simple HTTP file download.

     *

     * @param contentType like "text/csv" or "application/pdf"

     * @param fileName specifiy the name of the file you want to save

     * @param suffix file ending like "txt" or "pdf"

     * @param encoding charset like "utf-8"

     */

    public FileDownloadView(String contentType, String fileName, String suffix, String encoding){

        this.contentType = contentType;

        this.fileName = fileName;

        this.suffix = suffix;

        this.encoding = encoding;

    }

    @Override

    public void render(Map<String, ?> model, HttpServletRequest arg1, HttpServletResponse response) throws Exception {

        response.setContentType(getContentType() + (isBinaryData() ? "" : "; charset="+getEncoding().toLowerCase(Locale.ENGLISH)));

        if(!isBinaryData()){

            response.setCharacterEncoding(getEncoding().toUpperCase(Locale.ENGLISH));

        }

        response.setHeader("Content-Disposition", "attachment; filename=\""+getFileName()+"."+getSuffix()+"\"");

        //set File

        if(model.containsKey("file")){

            Object object = model.get("file");

            if(object instanceof File){

                try{

                    File file = (File) object;

                    FileInputStream fis = new FileInputStream(file);

                    if(!isBinaryData()){

                        InputStreamReader isr = new InputStreamReader(fis, getEncoding().toUpperCase(Locale.ENGLISH));

                        IOUtils.copy(isr, response.getWriter());

                    } else {

                        IOUtils.copy(fis, response.getOutputStream());

                    }

                    response.flushBuffer();

                }catch(IOException e){

                    throw new IOException("IOERROR writing file to outputstream \n" + e);

                }

            }

        }

    }

    @Override

    public String getContentType() {

        return contentType;

    }

    public void setContentType(String contentType){

        this.contentType = contentType;

    }

    public String getFileName() {

        return fileName;

    }

    public void setFileName(String fileName){

        this.fileName = fileName;

    }

    public String getSuffix() {

        return suffix;

    }

    public void setSuffix(String suffix){

        this.suffix = suffix;

    }

    public String getEncoding() {

        return encoding;

    }

    public void setEncoding(String encoding) {

        this.encoding = encoding;

    }

    protected boolean isBinaryData(){

        return encoding == null;

    }

}