在 Java 中将 InputStream 写入文件

Writing an InputStream to a File in Java

我正在编写此方法,它将 InputStream 转换为文件,但该方法适用于某些输入但不适用于所有输入(当我将 zip 文件作为 InputStream 传递时它有效)。它只是创建一个 0 字节的文件。

我知道之前有人问过这个问题,在任何人将其标记为重复之前,请检查我到目前为止所做的事情..

这是我目前尝试过的方法。大多数这些解决方案都是从 Whosebug 中找到的。

private void saveFile(String filename, InputStream input) throws IOException 
{
        if (filename == null) {
            return;
        }


        File file = new File(filename);


        //*************** 1st *****************

        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        System.out.println("This is inputStream:"+stringFromInputStream);
        FileUtils.writeStringToFile(file, StringFromInputStream);


        //********************2nd **********************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        byte[] aByte = StringFromInputStream.getBytes();
        FileOutputStream fos=new FileOutputStream(file);
        IOUtils.write(aByte, fos);


        //*******************3rd**********************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        byte[] aByte = StringFromInputStream.getBytes();
        FileOutputStream fos=new FileOutputStream(file);
        fos.write(aByte);


        //*********************4th*********************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        FileWriter fr=new FileWriter(file);
        BufferedWriter br=new BufferedWriter(fr);
        br.write(StringFromInputStream);
        br.flush();
        fr.flush();
        br.close();
        fr.close();



        //*************5th**********************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        Files.write(Paths.get(filename), StringFromInputStream.getBytes());


        //************************6th**************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        FileUtils.writeStringToFile(file, StringFromInputStream);


        //******************7th*********************
        String stringFromInputStream = IOUtils.toString(input, "UTF-8");
        FileWriter fileWriter = new FileWriter(file);
        PrintWriter printWriter = new PrintWriter(fileWriter);
        printWriter.print(StringFromInputStream);
        fileWriter.flush();
        fileWriter.close();


        //**********************8th*************************
        final Path destination = Paths.get(filename);
        try (
            final InputStream in = input;
        ) {
            Files.copy(in, destination,StandardCopyOption.REPLACE_EXISTING);
        }


        // ************* This one works but not for all(Sometimes creats a file with 0 bytes) ****************

        FileOutputStream fos = new FileOutputStream(file);
        BufferedOutputStream bos = new BufferedOutputStream(fos);
        BufferedInputStream bis = new BufferedInputStream(input);
        int aByte;
        while ((aByte = bis.read()) != -1) {
            bos.write(aByte);
        }
        bos.flush();
        fos.flush();
        bos.close();
        fos.close();
        bis.close();

        ........
}

你的大部分方法损坏文件是因为你将InputStream读入一个String变量(二进制文件会被损坏)。试试这个实现:

byte[] aByte = IOUtils.toByteArray(input);
FileOutputStream fos=new FileOutputStream(file);
IOUtils.write(aByte, fos);

FileOutputStream fos=new FileOutputStream(file);
IOUtils.copy(input, fos);