NTLM认证的proxy客户端的Java实现-Base64.java

需要的另外一个java文件。

public class Base64 {
 // for base64 encoding
 private static char[] map = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/="
   .toCharArray();

 // given a character, get it's index into the base64 character map
 private static int b64_index(char c) {
  if (c >= 'A' && c <= 'Z') {
   return c - 'A';
  } else if (c >= 'a' && c <= 'z') {
   return c - 'a' + 26;
  } else if (c >= '0' && c <= '9') {
   return c - '0' + 52;
  } else if (c == '+') {
   return 62;
  } else if (c == '/') {
   return 63;
  }
  return -1; // invalid or pad ('=') char
 }

 public static char[] encode(byte[] data) {
  if (data == null) {
   return null;
  }
  // every 3 bytes of the original data is encoded into 4 characters.
  // output is always a multiple of 4 chars, padded if needed.
  char[] out = new char[((data.length + 2) / 3) * 4];
  int val, i, index;
  boolean quad = false;
  boolean trip = false;
  index = 0;
  for (i = 0; i < data.length; i += 3) {
   quad = false;
   trip = false;
   val = (0xFF & (int) data[i]);
   val <<= 8;
   if ((i + 1) < data.length) {
    val |= (0xFF & (int) data[i + 1]);
    trip = true;
   }
   val <<= 8;
   if ((i + 2) < data.length) {
    val |= (0xFF & (int) data[i + 2]);
    quad = true;
   }
   out[index + 3] = map[(quad ? (val & 0x3F) : 64)];
   val >>= 6;
   out[index + 2] = map[(trip ? (val & 0x3F) : 64)];
   val >>= 6;
   out[index + 1] = map[val & 0x3F];
   val >>= 6;
   out[index + 0] = map[val & 0x3F];
   index += 4;
  }

  return out;
 }

 public static byte[] decode(char[] data) {
  int i;
  if (data == null) {
   return null;
  }

  // search data for and discount any illegal characters
  int templen = data.length;
  for (i = 0; i < data.length; i++) {
   if (b64_index(data[i]) < 0) {
    templen--;
   }
  }

  // calculate required length using templen:
  // 3 bytes for every 4 valid base64 chars
  // plus 2 bytes if there are 3 extra base64 chars,
  // or plus 1 byte if there are 2 extra.
  int len = (templen / 4) * 3;
  if ((templen % 4) == 3) {
   len += 2;
  }

  if ((templen % 4) == 2) {
   len += 1;
  }

  byte[] out = new byte[len];
  int shift = 0, // number of bits stored in accum
  accum = 0, // stored bits
  index = 0, // current index in output buffer
  value;

  // we now go through the entire array
  for (i = 0; i < data.length; i++) {
   if (index == len) {
    break; // should never happen, but let's be safe
   }
   value = b64_index(data[i]);
   if (value >= 0) {
    accum <<= 6; // bits shift up by 6 each time through
    shift += 6; // the loop, with new bits being put in
    accum |= value; // at the bottom.
    if (shift >= 8) { // whenever there are 8 or more shifted in,
     shift -= 8; // write them out from the top, leaving any
     // excess at the bottom for next iteration.
     out[index++] = (byte) ((accum >> shift) & 0xFF);
    }
   } // else character was illegal - skip it
  }

  return out;
 }
} // end Base64 class