您作为资深java专家,请使用java的 <groupId>net.digger</groupId> <artifactId>utils</artifactId> 包,编写ymodem文件传输工具类,方便调用
时间: 2023-11-07 09:05:06 浏览: 156
好的,下面是一个简单的ymodem文件传输工具类的实现,使用了net.digger.utils包中的一些工具类:
```java
package com.example.ymodem;
import net.digger.util.Hex;
import net.digger.util.HexFormatException;
import java.io.*;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
public class YModemTransfer {
private static final int PACKET_SIZE = 1024;
private static final int PACKET_OVERHEAD = 3;
private static final int PACKET_DATA_SIZE = PACKET_SIZE - PACKET_OVERHEAD;
private static final byte SOH = 0x01;
private static final byte STX = 0x02;
private static final byte EOT = 0x04;
private static final byte ACK = 0x06;
private static final byte NAK = 0x15;
private static final byte CAN = 0x18;
private static final byte CRC = 0x43;
private static final byte ABORT = 0x41;
private final InputStream in;
private final OutputStream out;
public YModemTransfer(InputStream in, OutputStream out) {
this.in = in;
this.out = out;
}
public void sendFile(File file) throws IOException, InterruptedException {
FileInputStream fis = new FileInputStream(file);
BufferedInputStream bis = new BufferedInputStream(fis);
sendHeader(file.getName(), file.length());
byte[] buffer = new byte[PACKET_DATA_SIZE];
int bytesRead;
int packetNumber = 0;
while ((bytesRead = bis.read(buffer)) != -1) {
byte[] packet = createPacket(packetNumber, buffer, bytesRead);
int attempts = 0;
boolean success = false;
while (!success && attempts < 10) {
out.write(packet);
int response = in.read();
if (response == ACK) {
success = true;
} else if (response == NAK) {
attempts++;
} else {
throw new IOException("Unexpected response: " + response);
}
}
if (!success) {
throw new IOException("Failed to send packet");
}
packetNumber++;
}
sendEOT();
bis.close();
fis.close();
}
private void sendHeader(String fileName, long fileSize) throws IOException, InterruptedException {
byte[] header = createHeader(fileName, fileSize);
int attempts = 0;
boolean success = false;
while (!success && attempts < 10) {
out.write(header);
int response = in.read();
if (response == ACK) {
success = true;
} else if (response == NAK) {
attempts++;
} else {
throw new IOException("Unexpected response: " + response);
}
}
if (!success) {
throw new IOException("Failed to send header");
}
}
private void sendEOT() throws IOException, InterruptedException {
int attempts = 0;
boolean success = false;
while (!success && attempts < 10) {
out.write(EOT);
int response = in.read();
if (response == ACK) {
success = true;
} else if (response == NAK) {
attempts++;
} else {
throw new IOException("Unexpected response: " + response);
}
}
if (!success) {
throw new IOException("Failed to send EOT");
}
}
private static byte[] createPacket(int packetNumber, byte[] data, int dataSize) throws IOException {
if (dataSize > PACKET_DATA_SIZE) {
throw new IllegalArgumentException("Data too large for packet");
}
ByteArrayOutputStream baos = new ByteArrayOutputStream();
baos.write(dataSize == PACKET_DATA_SIZE ? STX : SOH);
baos.write(packetNumber & 0xff);
baos.write((~packetNumber) & 0xff);
baos.write(data, 0, dataSize);
byte[] crc = calculateCrc(data, dataSize);
baos.write(crc[0]);
baos.write(crc[1]);
return baos.toByteArray();
}
private static byte[] createHeader(String fileName, long fileSize) throws IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
baos.write(SOH);
baos.write(0);
baos.write(~0);
byte[] fileNameBytes = fileName.getBytes(StandardCharsets.US_ASCII);
if (fileNameBytes.length > 128) {
throw new IllegalArgumentException("File name too long");
}
baos.write(fileNameBytes);
for (int i = 0; i < 128 - fileNameBytes.length; i++) {
baos.write(0);
}
byte[] fileSizeBytes = Long.toString(fileSize).getBytes(StandardCharsets.US_ASCII);
if (fileSizeBytes.length > 10) {
throw new IllegalArgumentException("File size too large");
}
for (int i = 0; i < 10 - fileSizeBytes.length; i++) {
baos.write(0);
}
baos.write(fileSizeBytes);
for (int i = 0; i < 128 - fileSizeBytes.length; i++) {
baos.write(0);
}
byte[] crc = calculateCrc(Arrays.copyOfRange(baos.toByteArray(), 3, 131), 128);
baos.write(crc[0]);
baos.write(crc[1]);
return baos.toByteArray();
}
private static byte[] calculateCrc(byte[] data, int dataSize) throws IOException {
try {
int crc = 0;
for (int i = 0; i < dataSize; i++) {
crc = updateCrc(crc, data[i]);
}
return Hex.toByteArray(Integer.toHexString(crc & 0xffff).toUpperCase());
} catch (HexFormatException e) {
throw new IOException("Failed to calculate CRC", e);
}
}
private static int updateCrc(int crc, byte data) {
crc = crc ^ ((int) data << 8);
for (int i = 0; i < 8; i++) {
if ((crc & 0x8000) != 0) {
crc = (crc << 1) ^ 0x1021;
} else {
crc = crc << 1;
}
}
return crc & 0xffff;
}
}
```
这个类包含了一个sendFile方法,它将给定的文件通过YModem协议传输到输出流中。要使用该方法,只需将输入流和输出流传递给YModemTransfer的构造函数,然后调用sendFile方法即可。
例如,以下代码将文件"example.bin"通过YModem协议传输到串口:
```java
SerialPort port = ...; // 获取串口对象
YModemTransfer transfer = new YModemTransfer(port.getInputStream(), port.getOutputStream());
transfer.sendFile(new File("example.bin"));
```
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