常用工具类(Base64、Md5)

常用工具类

MD5Util

public class MD5Util {
    /** 全局数组 **/
    private final static String[] strDigits = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "A", "B", "C", "D","E", "F" };
    /**
     * 返回形式为数字跟字符串
     * @param bByte
     * @return
     */
    private static String byteToArrayString(byte bByte) {
        int iRet = bByte;
        if (iRet < 0) {
            iRet += 256;
        }
        int iD1 = iRet / 16;
        int iD2 = iRet % 16;
        return strDigits[iD1] + strDigits[iD2];
    }
    /**
     * 转换字节数组为16进制字串
     * @param bByte
     * @return
     */
    private static String byteToString(byte[] bByte) {
        StringBuffer sBuffer = new StringBuffer();
        for (int i = 0; i < bByte.length; i++) {
            sBuffer.append(byteToArrayString(bByte[i]));
        }
        return sBuffer.toString();
    }

    public static String encode(String str) throws NoSuchAlgorithmException {
        String result = null;
        result = new String(str);
        MessageDigest md = MessageDigest.getInstance("MD5");
        result = byteToString(md.digest(str.getBytes()));
        return result;
    }

    public static String encode(String plaintext,String encoding)
            throws NoSuchAlgorithmException, UnsupportedEncodingException {
        byte[] hash;
        hash = MessageDigest.getInstance("MD5").digest(plaintext.getBytes(encoding));
        StringBuilder hex = new StringBuilder(hash.length * 2);
        for (byte b : hash) {
            if ((b & 0xFF) < 0x10) hex.append("0");
            hex.append(Integer.toHexString(b & 0xFF));
        }
        return hex.toString();
    }
}

Base64Util

public class Base64Util {

    public static String encoder(String plaintext, String encoding) throws UnsupportedEncodingException {
        final Base64.Encoder encoder = Base64.getEncoder();
        String strEncoder = null;

        strEncoder = encoder.encodeToString(plaintext.getBytes(encoding));
        return strEncoder;
    }

    public static String decoder(String plaintext, String encoding) throws UnsupportedEncodingException {
        final Base64.Decoder decoder = Base64.getDecoder();
        String strEncoder = null;
        strEncoder = new String(decoder.decode(plaintext), encoding);
        return strEncoder;
    }
}

ListUtil

//ListUtil.getIdList(Trade.class,List,"id") 来获取对象中的元素

public abstract class ListUtil {

    public static <T,D> List<T> listCover (Class<T> clazz, List<D> list){
        List<T> voList = new ArrayList<>();
        if(!CollectionUtils.isEmpty(list)){
            for (D d : list) {
                try {
                    T t = clazz.newInstance();
                    BeanUtils.copyProperties(d, t);
                    voList.add(t);
                } catch (Exception e) {
                    throw new BusinessException("listCover数据类型转换出错");
                }
            }
        }
        return voList;
    }


    /**
     * 提取对象数组的ID数组
     * @param classz
     * @param list
     * @param <T>
     * @return
     */
    public static <T> List<String> getIdList (Class<T> classz,List<T> list){
        List<String> idList = new ArrayList<>();
        try{
            Method method = classz.getMethod("getId");
            for(T t:list){
                String id = (String)method.invoke(t);
                idList.add(id);
            }
        }catch (Exception e){
            throw new BusinessException("获取ID数组出错");
        }
        return idList;
    }

    /**
     * 提取对象数组的ID数组
     * @param classz
     * @param list
     * @param <T>
     * @return
     */
    public static <T> List<String> getIdList (Class<T> classz, Collection<T> list, String idField){
        List<String> idList = new ArrayList<>();
        if(null != list && list.size() > 0){
            try{
                if(ObjectUtil.isNotNull(idField)){
                    char[] cs = idField.toCharArray();
                    cs[0]-=32;
                    Method method = classz.getMethod("get" + String.valueOf(cs));
                    for(T t:list){
                        String id = (String)method.invoke(t);
                        idList.add(id);
                    }
                }

            }catch (Exception e){
                throw new BusinessException("获取ID数组出错");
            }
        }
        return idList;
    }

    /**
     * 字符串转换List<Long>
     * @param str
     * @return
     */
    public static List<Long> stringCoverLongList(String str){
        List<Long> idList = new ArrayList<>();
        if(commaLinksCheck(str)){
            String [] strIds = StringUtils.split(str,",");
            for(String strId:strIds){
                idList.add(Long.parseLong(strId));
            }
        }
        return idList;
    }

    /**
     * 字符串转换List<String>
     * @param str
     * @return
     */
    public static List<String> commaLinksToList(String str){
        List<String> stringList = new ArrayList<>();
        if(commaLinksCheck(str)){
            String [] strIds = StringUtils.split(str,",");
            for(String strId:strIds){
                stringList.add(strId);
            }
        }
        return stringList;
    }

    /**
     * 检查是否标准的:1,2,3,4,5的字符串拼接
     * @param content
     * @return
     */
    public static boolean commaLinksCheck(String content){
        boolean bool = false;
        if(!StringUtils.isEmpty(content)){
           bool =  Pattern.matches("^(\\w+,)*\\w+$", content);
        }
        return bool;
    }

    public static String listCoverString(List<String> temp, String split) {
        StringBuilder sb = new StringBuilder();
        for (String tmp : temp) {
            sb.append(tmp).append(split);
        }
        return sb.toString();
    }
}