br.com.caelum.vraptor.observer.download.InputStreamDownload.java Source code

Introduction

Here is the source code for br.com.caelum.vraptor.observer.download.InputStreamDownload.java

Source

/***
 * Copyright (c) 2009 Caelum - www.caelum.com.br/opensource
 * All rights reserved.
 *
 * 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 br.com.caelum.vraptor.observer.download;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import javax.enterprise.inject.Vetoed;
import javax.servlet.http.HttpServletResponse;

import com.google.common.io.ByteStreams;

/**
 * Handles download by reading from a input stream byte by byte.
 *
 * @author filipesabella
 * @author Paulo Silveira
 *
 * @see ByteArrayDownload
 * @see FileDownload
 */
@Vetoed
public class InputStreamDownload implements Download {
    private final InputStream stream;
    private final String contentType;
    private final String fileName;
    private final boolean doDownload;
    private final long size;

    public InputStreamDownload(InputStream input, String contentType, String fileName) {
        this(input, contentType, fileName, false, 0);
    }

    public InputStreamDownload(InputStream input, String contentType, String fileName, boolean doDownload,
            long size) {
        this.stream = input;
        this.size = size;
        this.contentType = contentType;
        this.fileName = fileName;
        this.doDownload = doDownload;
    }

    @Override
    public void write(HttpServletResponse response) throws IOException {
        writeDetails(response);

        OutputStream out = response.getOutputStream();
        ByteStreams.copy(stream, out);
    }

    void writeDetails(HttpServletResponse response) {
        if (contentType != null) {
            String contentDisposition = String.format("%s; filename=%s", doDownload ? "attachment" : "inline",
                    fileName);
            response.setHeader("Content-disposition", contentDisposition);
            response.setHeader("Content-type", contentType);
        }

        if (size > 0) {
            response.setHeader("Content-Length", Long.toString(size));
        }
    }
}