从Java中的串行读取特定字节数

Question

I am reading bytes from a SD using arduino to a java application. this is my approach:

 if(temp.contains("_i_;")){
                imgByte = new ArrayList<>();
                imgByte.clear();

             for(int i=0; i< min(imgSize , 64) ;i++){
                                    imgByte.add((byte)rx.getInputStream().read());

                                             imgSize--;
             }  
             Files.write(imgFile, toByteArray(imgByte),StandardOpenOption.APPEND );
             System.out.println("Left: "+imgSize);
                   return true; 
             }

i ; is just indicates a 64 packet is coming.

but it is too slow that i can't receive the picture on time. is there another way for doing that so i can read all 64 bytes in only one line? and not iterating with a for loop? PS: toByteArray converts byte ArrayList to byte[] so i can write it to file . I am using jSerialComm library from serial communication

Answer 1

你有没有尝试过

Files.copy(rx.getInputStream(), imgFile);

Answer 2

I solved the problem in the following way:

if(temp.contains("_i_;")){
                imgByte = new ArrayList<>();
                imgByte.clear();
                byte[] data = new byte[64];
            // for(int i=0; i< min(imgSize , 64) ;i++){
                                   // imgByte.add((byte)rx.getInputStream().read());
                                   rx.getInputStream().read(data, 0, min(imgSize , 64));
                                             imgSize-=min(imgSize , 64);
           //  }  
             //Files.write(imgFile, toByteArray(imgByte),StandardOpenOption.APPEND );
             Files.write(imgFile, data,StandardOpenOption.APPEND );
             System.out.println("Left: "+imgSize);
                   return true; 
             }