java文件读写操作

文件读为流，文件读为byte[]
byte[]写为文件，流写为文件
记录一下

    
    public byte[] readFilebyByte(String fileUrl) throws Exception {
        return this.streamByByte(new FileInputStream(fileUrl));
    }

    
    public InputStream readFileByStream(String fileUrl) throws Exception {
        return new DataInputStream(new FileInputStream(fileUrl));
    }

    
    public InputStream byteByStream(byte[] data) throws Exception {
        return new ByteArrayInputStream(data);
    }

    
    public byte[] streamByByte(InputStream inStream) throws Exception {
        ByteArrayOutputStream outStream = null;
        try {
            outStream = new ByteArrayOutputStream();
            byte[] buffer = new byte[1024];
            int len;
            while ((len = inStream.read(buffer)) != -1) {
                outStream.write(buffer, 0, len);
            }
            return outStream.toByteArray();
        } finally {
            outStream.close();
            inStream.close();
        }
    }

    
    public void saveFile(InputStream inStream, String saveUrl) throws Exception {
        try {
            this.saveFile(this.streamByByte(inStream), saveUrl);
        } finally {
            inStream.close();
        }
    }

    
    public void saveFile(byte[] data, String saveUrl) throws Exception {
        FileOutputStream fileOutStream = null;
        try {
            fileOutStream = new FileOutputStream(saveUrl);
            fileOutStream.write(data);
        } finally {
            fileOutStream.close();
        }
    }

    public static void main(String[] args) throws Exception {
        FileUtil fileUtil = new FileUtil();
        byte[] in = fileUtil.readFilebyByte("C:\111.png");
        fileUtil.saveFile(fileUtil.byteByStream(in), "C:\222.png");
    }