Java 方便调用的工具类

//时间格式化 （string型转date型 date转string）//String pattern 如：yyyy-MM-dd hh:mm:ssprivate static Map<String, DateFormat> dateFormatMap = new HashMap<String, DateFormat>();public synchronized static String date2Str(Date date, String pattern) {String result = null;DateFormat df = null;if (dateFormatMap.containsKey(pattern)) {df = dateFormatMap.get(pattern);} else {df = new SimpleDateFormat(pattern);dateFormatMap.put(pattern, df);}try {result = df.format(date);} catch (Exception e) {e.printStackTrace();}return result;}public synchronized static Date str2Date(String dateStr, String pattern) {Date date = null;DateFormat df = null;if (dateFormatMap.containsKey(pattern)) {df = dateFormatMap.get(pattern);} else {df = new SimpleDateFormat(pattern);dateFormatMap.put(pattern, df);}try {date = df.parse(dateStr);} catch (Exception e) {}return date;}/** * 获取登录IP * */public static String getLocalIp(){String ip=null;try {ip= InetAddress.getLocalHost().toString();} catch (UnknownHostException e) {// TODO Auto-generated catch blocke.printStackTrace();}return ip;}       /** * 分转化为元 *  * @param fen */public static float fen2Yuan(long fen) {BigDecimal bg = new BigDecimal(Long.toString(fen));BigDecimal rate = new BigDecimal("0.01");return bg.multiply(rate).floatValue();}/** *  * 将字符串的变成以分为计量单位的long型数字 *  * @param number * @return */public static long getMoneyByFen(String number, boolean calculateByYuan)throws NumberFormatException {if (isNullOrEmpty(number)) {throw new NumberFormatException();}long result = 0;// 0.21,1.23if (number.indexOf(".") != -1) {if (!isFloat(number)) {throw new NumberFormatException();}Float floatNumber = Float.parseFloat(number);BigDecimal bd = new BigDecimal(Float.toString(floatNumber));result = (bd.multiply(new BigDecimal("100"))).longValue();} else {if (!isLongNumber(number)) {throw new NumberFormatException();} else if (calculateByYuan) {BigDecimal bd = new BigDecimal(number);result = (bd.multiply(new BigDecimal("100"))).longValue();} else {result = Long.parseLong(number);}}return result;}public static Date getLocalDateTime() {java.util.Calendar c = java.util.Calendar.getInstance();java.text.SimpleDateFormat f = new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm:ss");Date date = Tool.str2Date(f.format(c.getTime()),Constant.DATE_PATTERN_BASE);return date;}