import java.nio.charset.StandardCharsets;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
public class ByteUtil {
/**
* 字符串转16进制
*
* @param hexString
* @return
*/
public static byte[] hexStringToBytes(String hexString) {
if (hexString == null || "".equals(hexString)) {
return null;
}
// toUpperCase将字符串中的所有字符转换为大写
hexString = hexString.toUpperCase();
int length = hexString.length() / 2;
// toCharArray将此字符串转换为一个新的字符数组。
char[] hexChars = hexString.toCharArray();
byte[] d = new byte[length];
for (int i = 0; i < length; i++) {
int pos = i * 2;
d[i] = (byte) (charToByte(hexChars[pos]) << 4 | charToByte(hexChars[pos + 1]));
}
return d;
}
/**
* charToByte返回在指定字符的第一个发生的字符串中的索引，即返回匹配字符
*
* @param c
* @return
*/
private static byte charToByte(char c) {
return (byte) "0123456789ABCDEF".indexOf(c);
}
/**
* 将字节数组转换为16进制字符串
*
* @param bytes
* @return
*/
public static String binaryToHexString(byte[] bytes) {
String hexStr = "0123456789ABCDEF";
StringBuilder result = new StringBuilder();
String hex = "";
for (byte b : bytes) {
hex = String.valueOf(hexStr.charAt((b & 0xF0) >> 4));
hex += String.valueOf(hexStr.charAt(b & 0x0F));
result.append(hex).append(" ");
}
return result.toString();
}
/**
* 截取指定位置判断消息类型
*
* @param position
* @param data
* @return
*/
public static String getFunctionCode(int[] position, String[] data) {
StringBuilder builder = new StringBuilder("");
for (int i : position) {
try {
builder.append(data[i]);
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
return builder.toString();
}
/**
* Hex字符串转Byte
*
* @param hex 范围为0x00到0xFF
* @return
*/
public static byte hexToByte(String hex) {
return (byte) Integer.parseInt(hex, 16);
}
/**
* @param hex
* @return
*/
public static String hexToNumber(String hex) {
hex = hex.replaceAll(" ", "");
StringBuilder intString = new StringBuilder();
for (int i = 0; i < hex.length(); i += 2) {
String tem = hex.substring(i, i + 2);
intString.append(Integer.parseInt(tem, 16));
}
return intString.toString();
}
/**
* 16进制表示的字符串转换为字节数组
*
* @param hexString
* @return
*/
public static byte[] hexStringToByteArray(String hexString) {
hexString = hexString.replaceAll(" ", "");
int len = hexString.length();
byte[] bytes = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
// 两位一组，表示一个字节,把这样表示的16进制字符串，还原成一个字节
bytes[i / 2] = (byte) ((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16));
}
return bytes;
}
/**
* int转16进制字符串（两个字节）
*
* @param v
* @return
*/
public static String intToHexString(int v) {
return String.format("%04x", v);
}
/**
* int转16进制字符串（1个字节）
*
* @param v
* @return
*/
public static String intToHexStringSingle(int v) {
return String.format("%02x", v);
}
/**
* 16进制字符串转int（两个字节）
*
* @param hex
* @return
*/
public static int hexStringToInt(String hex) {
return Integer.parseInt(hex.replaceAll(" ", ""), 16);
}
/**
* 字符串转化成为16进制字符串
*
* @param s
* @return
*/
public static String strTo16(String s) {
StringBuilder str = new StringBuilder();
for (int i = 0; i < s.length(); i++) {
int ch = s.charAt(i);
String s4 = Integer.toHexString(ch);
str.append(s4);
}
return str.toString();
}
/**
* 字节数组转16进制
*
* @param bytes 需要转换的byte数组
* @return 转换后的Hex字符串
*/
public static String bytesToHex(byte[] bytes) {
StringBuilder sb = new StringBuilder();
for (byte aByte : bytes) {
String hex = Integer.toHexString(aByte & 0xFF);
if (hex.length() < 2) {
sb.append(0);
}
sb.append(hex);
}
return sb.toString();
}
/**
* 日期转换7个字节
*
* @param date
* @return
*/
public static byte[] dateToBytes(Date date) {
SimpleDateFormat df = new SimpleDateFormat("yyyy MM dd HH mm ss");
String str = df.format(date);
String[] strings = str.split(" ");
String[] newStrings = new String[5];
System.arraycopy(strings, 1, newStrings, 0, strings.length - 1);
byte[] bytes = new byte[7];
byte[] temByte = ByteUtil.hexStringToByteArray(ByteUtil.intToHexString(Integer.parseInt(strings[0])));
bytes[0] = temByte[0];
bytes[1] = temByte[1];
int i = 2;
for (String s : newStrings) {
bytes[i] = ByteUtil.hexStringToByteArray(ByteUtil.intToHexStringSingle(Integer.parseInt(s)))[0];
i++;
}
return bytes;
}
/**
* 7个字节转日期
*
* @param hex
* @return
*/
public static Date hexToDate(String hex) {
Date date = null;
SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
StringBuilder sBuf = new StringBuilder();
sBuf.append(Integer.parseInt(hex.substring(0, 4), 16));
String str = hex.substring(4);
for (int i = 0; i < str.length(); i = i + 2) {
int num = Integer.parseInt(str.substring(i, i + 2), 16);
sBuf.append(String.format("%02d", num));
}
try {
date = df.parse(sBuf.toString());
} catch (ParseException e) {
e.printStackTrace();
}
return date;
}
/**
* 产生numSize位16进制随机数
*
* @param numSize
* @return
*/
public static String getRandomValue(int numSize) {
StringBuilder str = new StringBuilder();
for (int i = 0; i < numSize; i++) {
char temp = 0;
int key = (int) (Math.random() * 2);
switch (key) {
case 0:
//产生随机数字
temp = (char) (Math.random() * 10 + 48);
break;
case 1:
//产生a-f
temp = (char) (Math.random() * 6 + 'a');
break;
default:
break;
}
str.append(temp);
}
return str.toString();
}
public static void main(String[] args) {
int v = 59466;
byte[] byteArray = ByteUtil.hexStringToByteArray(ByteUtil.intToHexString(v));
byte[] byteArray2 = Integer.toHexString(v).getBytes(StandardCharsets.UTF_8);
System.out.println();
}
