import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;

import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
import org.apache.commons.lang.StringEscapeUtils;

/**
 * 各種格式的編碼加碼工具類.
 * 
 * 集成Commons-Codec,Commons-Lang及JDK提供的編解碼方法.
 * 
 *  
 */
public class EncodeUtils {

 private static final String DEFAULT_URL_ENCODING = "UTF-8";

 /**
  * Hex編碼.
  */
 /*public static String hexEncode(byte[] input) {
  return Hex.encodeHexString(input);
 }*/

 /**
  * Hex解碼.
  */
 public static byte[] hexDecode(String input) {
  try {
   return Hex.decodeHex(input.toCharArray());
  } catch (DecoderException e) {
   throw new IllegalStateException("Hex Decoder exception", e);
  }
 }

 /**
  * Base64編碼.
  */
 public static String base64Encode(byte[] input) {
  return new String(Base64.encodeBase64(input));
 }

 /**
  * Base64編碼, URL安全(將Base64中的URL非法字符??,/=轉為其他字符, 見RFC3548).
  */
 public static String base64UrlSafeEncode(byte[] input) {
  return Base64.encodeBase64URLSafeString(input);
 }

 /**
  * Base64解碼.
  */
 public static byte[] base64Decode(String input) {
  return Base64.decodeBase64(input);
 }

 /**
  * URL 編碼, Encode默認為UTF-8. 
  */
 public static String urlEncode(String input) {
  try {
   return URLEncoder.encode(input, DEFAULT_URL_ENCODING);
  } catch (UnsupportedEncodingException e) {
   throw new IllegalArgumentException("Unsupported Encoding Exception", e);
  }
 }

 /**
  * URL 解碼, Encode默認為UTF-8. 
  */
 public static String urlDecode(String input) {
  try {
   return URLDecoder.decode(input, DEFAULT_URL_ENCODING);
  } catch (UnsupportedEncodingException e) {
   throw new IllegalArgumentException("Unsupported Encoding Exception", e);
  }
 }

 /**
  * Html 轉碼.
  */
 public static String htmlEscape(String html) {
  return StringEscapeUtils.escapeHtml(html);
 }

 /**
  * Html 解碼.
  */
 public static String htmlUnescape(String htmlEscaped) {
  return StringEscapeUtils.unescapeHtml(htmlEscaped);
 }

 /**
  * Xml 轉碼.
  */
 public static String xmlEscape(String xml) {
  return StringEscapeUtils.escapeXml(xml);
 }

 /**
  * Xml 解碼.
  */
 public static String xmlUnescape(String xmlEscaped) {
  return StringEscapeUtils.unescapeXml(xmlEscaped);
 }
}