Java实现的进制转换工具类完整示例

本文实例讲述了Java实现的进制转换工具类。分享给大家供大家参考，具体如下：

import java.nio.charset.Charset;

public class HexKit {
  
  private static final char[] DIGITS_LOWER = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
  
  private static final char[] DIGITS_UPPER = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
  //---------------------------------------------------------------------------------------------------- encode
  
  public static char[] encodeHex(byte[] data) {
    return encodeHex(data, true);
  }
  
  public static char[] encodeHex(String str, Charset charset) {
    return encodeHex(StrKit.getBytes(str, charset), true);
  }
  
  public static char[] encodeHex(byte[] data, boolean toLowerCase) {
    return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
  }
  
  public static String encodeHexStr(byte[] data) {
    return encodeHexStr(data, true);
  }
  
  public static String encodeHexStr(byte[] data, boolean toLowerCase) {
    return encodeHexStr(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
  }
  //---------------------------------------------------------------------------------------------------- decode
  
  public static String decodeHexStr(String hexStr, Charset charset) {
    if(StrKit.isEmpty(hexStr)){
      return hexStr;
    }
    return decodeHexStr(hexStr.toCharArray(), charset);
  }
  
  public static String decodeHexStr(char[] hexData, Charset charset) {
    return StrKit.str(decodeHex(hexData), charset);
  }
  
  public static byte[] decodeHex(char[] hexData) {
    int len = hexData.length;
    if ((len & 0x01) != 0) {
      throw new RuntimeException("Odd number of characters.");
    }
    byte[] out = new byte[len >> 1];
    // two characters form the hex value.
    for (int i = 0, j = 0; j < len; i++) {
      int f = toDigit(hexData[j], j) << 4;
      j++;
      f = f | toDigit(hexData[j], j);
      j++;
      out[i] = (byte) (f & 0xFF);
    }
    return out;
  }
  //---------------------------------------------------------------------------------------- Private method start
  
  private static String encodeHexStr(byte[] data, char[] toDigits) {
    return new String(encodeHex(data, toDigits));
  }
  
  private static char[] encodeHex(byte[] data, char[] toDigits) {
    int l = data.length;
    char[] out = new char[l << 1];
    // two characters form the hex value.
    for (int i = 0, j = 0; i < l; i++) {
      out[j++] = toDigits[(0xF0 & data[i]) >>> 4];
      out[j++] = toDigits[0x0F & data[i]];
    }
    return out;
  }
  
  private static int toDigit(char ch, int index) {
    int digit = Character.digit(ch, 16);
    if (digit == -1) {
      throw new RuntimeException("Illegal hexadecimal character " + ch + " at index " + index);
    }
    return digit;
  }
  //---------------------------------------------------------------------------------------- Private method end
  
  public static String binary2Hex(String bString) {
    if (bString == null || bString.equals("") || bString.length() % 8 != 0)
      return null;
    StringBuffer tmp = new StringBuffer();
    int iTmp = 0;
    for (int i = 0; i < bString.length(); i += 4) {
      iTmp = 0;
      for (int j = 0; j < 4; j++) {
 iTmp += Integer.parseInt(bString.substring(i + j, i + j + 1)) << (4 - j - 1);
      }
      tmp.append(Integer.toHexString(iTmp));
    }
    return tmp.toString();
  }
  
  public static String hex2Binary(String hexString) {
    if (hexString == null || hexString.length() % 2 != 0)
      return null;
    String bString = "", tmp;
    for (int i = 0; i < hexString.length(); i++) {
      tmp = "0000" + Integer.toBinaryString(Integer.parseInt(hexString.substring(i, i + 1), 16));
      bString += tmp.substring(tmp.length() - 4);
    }
    return bString;
  }
  
  public static String binary2Hex(byte buf[]) {
    StringBuffer sb = new StringBuffer();
    for (int i = 0; i < buf.length; i++) {
      String hex = Integer.toHexString(buf[i] & 0xFF);
      if (hex.length() == 1) {
 hex = '0' + hex;
      }
      sb.append(hex.toUpperCase());
    }
    return sb.toString();
  }
  
  public static byte[] hex2Byte(String hexStr) {
    if (hexStr.length() < 1)
      return null;
    byte[] result = new byte[hexStr.length() / 2];
    for (int i = 0; i < hexStr.length() / 2; i++) {
      int high = Integer.parseInt(hexStr.substring(i * 2, i * 2 + 1), 16);
      int low = Integer.parseInt(hexStr.substring(i * 2 + 1, i * 2 + 2), 16);
      result[i] = (byte) (high * 16 + low);
    }
    return result;
  }
}

PS：这里再为大家推荐几款本站的在线进制转换与计算工具，相信对于大家能有所帮助：

在线任意进制转换工具：
http://tools.jb51.net/transcoding/hexconvert

在线标准计算器：
http://tools.jb51.net/jisuanqi/jsq

在线科学计算器：
http://tools.jb51.net/jisuanqi/jsqkexue

更多关于java算法相关内容感兴趣的读者可查看本站专题：《Java数据结构与算法教程》、《Java操作DOM节点技巧总结》、《Java文件与目录操作技巧汇总》和《Java缓存操作技巧汇总》

希望本文所述对大家java程序设计有所帮助。