java類比PHP的pack和unpack類_php技巧

本文執行個體為大家分享了java類比PHP的pack和unpack類的具體代碼，供大家參考，具體內容如下

package qghl.intp.util; import java.io.IOException;import java.io.InputStream; public class PackUtil{     /**     * 打包字串     * 類似php中pack在java中的實現     *     * @param str     * @return     */    public static byte[] pack(String str) {      int nibbleshift = 4;      int position = 0;      int len = str.length() / 2 + str.length() % 2;      byte[] output = new byte[len];      for (char v : str.toCharArray()) {        byte n = (byte) v;        if (n >= '0' && n <= '9') {          n -= '0';        } else if (n >= 'A' && n <= 'F') {          n -= ('A' - 10);        } else if (n >= 'a' && n <= 'f') {          n -= ('a' - 10);        } else {          continue;        }        output[position] |= (n << nibbleshift);         if (nibbleshift == 0) {          position++;        }        nibbleshift = (nibbleshift + 4) & 7;      }       return output;    }     /**     * 16進位的字元解壓 類php中unpack     *     * @param is     * @param len     * @return     * @throws IOException     */    public static String unpack(InputStream is, int len) throws IOException {      byte[] bytes = new byte[len];      is.read(bytes);      return unpack(bytes);    }     /***     * 16進位的字元解壓 類php中unpack     * @param bytes     * @return     */    public static String unpack(byte[] bytes) {      StringBuilder stringBuilder = new StringBuilder("");      if (bytes == null || bytes.length <= 0) {        return null;      }      for (int i = 0; i < bytes.length; i++) {        int v = bytes[i] & 0xFF;        String hv = Integer.toHexString(v);        if (hv.length() < 2) {          stringBuilder.append(0);        }        stringBuilder.append(hv);      }      return stringBuilder.toString();    }  }

以上就是本文的全部內容，希望對大家學習java程式設計有所協助。