org.shimlib.web.servlet.view.filedownload.FileDownloadView.java Source code

Introduction

Here is the source code for org.shimlib.web.servlet.view.filedownload.FileDownloadView.java

Source

/*
*      Copyright 2011 Spitfire Lab Inc.
*
*   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.
*
*/

package org.shimlib.web.servlet.view.filedownload;

import org.springframework.util.FileCopyUtils;
import org.springframework.web.servlet.view.AbstractView;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.Map;

public class FileDownloadView extends AbstractView {
    public static final String VIEW_NAME_KEY = "shim-file-download-view";
    public static final String MODEL_NAME_KEY = "shim-file-download-file";

    protected static final String CONTENT_DISPOSITION = "Content-Disposition";

    @Override
    public String getContentType() {
        return null;
    }

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

    @Override
    protected void renderMergedOutputModel(Map<String, Object> model, HttpServletRequest request,
            HttpServletResponse response) throws Exception {
        IDownloadFile downloadFile = (IDownloadFile) model.get(MODEL_NAME_KEY);

        response.setContentType(downloadFile.getContentType());

        if (downloadFile.isInlineAttachment()) {
            response.setHeader(CONTENT_DISPOSITION, buildContentDisposition(downloadFile.getFileName()));
        }

        ByteArrayOutputStream baos = createTemporaryOutputStream();
        FileCopyUtils.copy(downloadFile.getInputStream(), baos);
        writeToResponse(response, baos);
    }

    @Override
    protected void writeToResponse(HttpServletResponse response, ByteArrayOutputStream baos) throws IOException {
        response.setContentLength(baos.size());

        // Flush byte array to servlet output stream.
        ServletOutputStream out = response.getOutputStream();
        baos.writeTo(out);
        out.flush();
    }

    protected String buildContentDisposition(String filename) {
        return new StringBuilder("attachment; filename=").append(filename).toString();
    }
}