java 讀取本地文件並轉換為byte數組

　　　　　private byte[] InputStream2ByteArray(String filePath) throws IOException { InputStream in = new FileInputStream(filePath); byte[] data = toByteArray(in); in.close(); return data; } private byte[] toByteArray(InputStream in) throws IOException { ByteArrayOutputStream out = new ByteArrayOutputStream(); byte[] buffer = new byte[1024 * 4]; int n = 0; while ((n = in.read(buffer)) != -1) { out.write(buffer, 0, n); } return out.toByteArray(); }