JAVA 串口读取16进制数问题

使用的是RXTXCOMM.JAR
关键代码如下
SerialPort serialPort;
InputStream inputStream;
byte[] readBuffer = new byte[1024];
int numBytes = 0;
inputStream = serialPort.getInputStream();
try {
while (inputStream.available() > 0) {
numBytes = inputStream.read(readBuffer);
System.out.print(new String(readBuffer));
}

} catch (IOException e) {
}

字符串可正常读取，但是16进制数读出的就是乱码