Java字符串的压缩与解压缩的两种方法

/**
 * 使用gzip压缩字符串
 * @param str 要压缩的字符串
 * @return
 */
public static String compress(String str) {
  if (str == null || str.length() == 0) {
    return str;
  }
  ByteArrayOutputStream out = new ByteArrayOutputStream();
  GZIPOutputStream gzip = null;
  try {
    gzip = new GZIPOutputStream(out);
    gzip.write(str.getBytes());
  } catch (IOException e) {
    e.printStackTrace();
  } finally {
    if (gzip != null) {
      try {
        gzip.close();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
  }
  return new sun.misc.BASE64Encoder().encode(out.toByteArray());
}
 
/**
 * 使用gzip解压缩
 * @param compressedStr 压缩字符串
 * @return
 */
public static String uncompress(String compressedStr) {
  if (compressedStr == null) {
    return null;
  }
 
  ByteArrayOutputStream out = new ByteArrayOutputStream();
  ByteArrayInputStream in = null;
  GZIPInputStream ginzip = null;
  byte[] compressed = null;
  String decompressed = null;
  try {
    compressed = new sun.misc.BASE64Decoder().decodeBuffer(compressedStr);
    in = new ByteArrayInputStream(compressed);
    ginzip = new GZIPInputStream(in);
    byte[] buffer = new byte[1024];
    int offset = -1;
    while ((offset = ginzip.read(buffer)) != -1) {
      out.write(buffer, 0, offset);
    }
    decompressed = out.toString();
  } catch (IOException e) {
    e.printStackTrace();
  } finally {
    if (ginzip != null) {
      try {
        ginzip.close();
      } catch (IOException e) {
      }
    }
    if (in != null) {
      try {
        in.close();
      } catch (IOException e) {
      }
    }
    if (out != null) {
      try {
        out.close();
      } catch (IOException e) {
      }
    }
  }
  return decompressed;
}

/**
 * 使用org.apache.commons.codec.binary.Base64压缩字符串
 * @param str 要压缩的字符串
 * @return
 */
public static String compress(String str) {
  if (str == null || str.length() == 0) {
    return str;
  }
  return Base64.encodeBase64String(str.getBytes());
}
 
/**
 * 使用org.apache.commons.codec.binary.Base64解压缩
 * @param compressedStr 压缩字符串
 * @return
 */
public static String uncompress(String compressedStr) {
  if (compressedStr == null) {
    return null;
  }
  return Base64.decodeBase64(compressedStr);
}