从文件得到ByteArrayOutputStream

public static ByteArrayOutputStream getOutputStream(String filePath){File file = new File(filePath);FileInputStream in = null;ByteArrayOutputStream out = new ByteArrayOutputStream();try {in = new FileInputStream(file);byte[] buffer = new byte[in.available()];in.read(buffer);out.write(buffer);} catch (Exception e) {e.printStackTrace();}finally{try {if(in!=null) in.close();} catch (Exception e2) {}}return out;}