java自定义封装StringUtils常用工具类

package com.demo.utils;import java.util.ArrayList;import java.util.List;import java.util.Map;/** * 字符串操作工具类 * @author dongyangyang * @Date 2016/12/28 23:12 * @Version 1.0 * */public class StringUtils { /**  * 首字母变小写  * @param str  * @return  */ public static String firstCharToLowerCase(String str) {  char firstChar = str.charAt(0);  if (firstChar >= 'A' && firstChar <= 'Z') {   char[] arr = str.toCharArray();   arr[0] += ('a' - 'A');   return new String(arr);  }  return str; } /**  * 首字母变大写  * @param str  * @return  */ public static String firstCharToUpperCase(String str) {  char firstChar = str.charAt(0);  if (firstChar >= 'a' && firstChar <= 'z') {   char[] arr = str.toCharArray();   arr[0] -= ('a' - 'A');   return new String(arr);  }  return str; } /**  * 判断是否为空  * @param str  * @return  */ public static boolean isEmpty(final String str) {  return (str == null) || (str.length() == 0); } /**  * 判断是否不为空  * @param str  * @return  */ public static boolean isNotEmpty(final String str) {  return !isEmpty(str); } /**  * 判断是否空白  * @param str  * @return  */ public static boolean isBlank(final String str) {  int strLen;  if ((str == null) || ((strLen = str.length()) == 0))   return true;  for (int i = 0; i < strLen; i++) {   if (!Character.isWhitespace(str.charAt(i))) {    return false;   }  }  return true; } /**  * 判断是否不是空白  * @param str  * @return  */ public static boolean isNotBlank(final String str) {  return !isBlank(str); } /**  * 判断多个字符串全部是否为空  * @param strings  * @return  */ public static boolean isAllEmpty(String... strings) {  if (strings == null) {   return true;  }  for (String str : strings) {   if (isNotEmpty(str)) {    return false;   }  }  return true; } /**  * 判断多个字符串其中任意一个是否为空  * @param strings  * @return  */ public static boolean isHasEmpty(String... strings) {  if (strings == null) {   return true;  }  for (String str : strings) {   if (isEmpty(str)) {    return true;   }  }  return false; } /**  * checkValue为 null 或者为 "" 时返回 defaultValue  * @param checkValue  * @param defaultValue  * @return  */ public static String isEmpty(String checkValue, String defaultValue) {  return isEmpty(checkValue) ? defaultValue : checkValue; } /**  * 字符串不为 null 而且不为 "" 并且等于other  * @param str  * @param other  * @return  */ public static boolean isNotEmptyAndEquelsOther(String str, String other) {  if (isEmpty(str)) {   return false;  }  return str.equals(other); } /**  * 字符串不为 null 而且不为 "" 并且不等于other  * @param str  * @param other  * @return  */ public static boolean isNotEmptyAndNotEquelsOther(String str, String... other) {  if (isEmpty(str)) {   return false;  }  for (int i = 0; i < other.length; i++) {   if (str.equals(other[i])) {    return false;   }  }  return true; } /**  * 字符串不等于other  * @param str  * @param other  * @return  */ public static boolean isNotEquelsOther(String str, String... other) {  for (int i = 0; i < other.length; i++) {   if (other[i].equals(str)) {    return false;   }  }  return true; } /**  * 判断字符串不为空  * @param strings  * @return  */ public static boolean isNotEmpty(String... strings) {  if (strings == null) {   return false;  }  for (String str : strings) {   if (str == null || "".equals(str.trim())) {    return false;   }  }  return true; } /**  * 比较字符相等  * @param value  * @param equals  * @return  */ public static boolean equals(String value, String equals) {  if (isAllEmpty(value, equals)) {   return true;  }  return value.equals(equals); } /**  * 比较字符串不相等  * @param value  * @param equals  * @return  */ public static boolean isNotEquals(String value, String equals) {  return !equals(value, equals); } public static String[] split(String content, String separatorChars) {  return splitWorker(content, separatorChars, -1, false); } public static String[] split(String str, String separatorChars, int max) {  return splitWorker(str, separatorChars, max, false); } public static final String[] EMPTY_STRING_ARRAY = new String[0]; private static String[] splitWorker(String str, String separatorChars, int max, boolean preserveAllTokens) {  if (str == null) {   return null;  }  int len = str.length();  if (len == 0) {   return EMPTY_STRING_ARRAY;  }  List<String> list = new ArrayList<String>();  int sizePlus1 = 1;  int i = 0, start = 0;  boolean match = false;  boolean lastMatch = false;  if (separatorChars == null) {   while (i < len) {    if (Character.isWhitespace(str.charAt(i))) {     if (match || preserveAllTokens) {      lastMatch = true;      if (sizePlus1++ == max) {       i = len;       lastMatch = false;      }      list.add(str.substring(start, i));      match = false;     }     start = ++i;     continue;    }    lastMatch = false;    match = true;    i++;   }  } else if (separatorChars.length() == 1) {   char sep = separatorChars.charAt(0);   while (i < len) {    if (str.charAt(i) == sep) {     if (match || preserveAllTokens) {      lastMatch = true;      if (sizePlus1++ == max) {       i = len;       lastMatch = false;      }      list.add(str.substring(start, i));      match = false;     }     start = ++i;     continue;    }    lastMatch = false;    match = true;    i++;   }  } else {   while (i < len) {    if (separatorChars.indexOf(str.charAt(i)) >= 0) {     if (match || preserveAllTokens) {      lastMatch = true;      if (sizePlus1++ == max) {       i = len;       lastMatch = false;      }      list.add(str.substring(start, i));      match = false;     }     start = ++i;     continue;    }    lastMatch = false;    match = true;    i++;   }  }  if (match || (preserveAllTokens && lastMatch)) {   list.add(str.substring(start, i));  }  return (String[]) list.toArray(EMPTY_STRING_ARRAY); } /**  * 消除转义字符  * @param str  * @return  */ public static String escapeXML(String str) {  if (str == null)   return "";  StringBuilder sb = new StringBuilder();  for (int i = 0; i < str.length(); ++i) {   char c = str.charAt(i);   switch (c) {   case '/u00FF':   case '/u0024':    break;   case '&':    sb.append("&");    break;   case '<':    sb.append("<");    break;   case '>':    sb.append(">");    break;   case '/"':    sb.append(""");    break;   case '/'':    sb.append("'");    break;   default:    if (c >= '/u0000' && c <= '/u001F')     break;    if (c >= '/uE000' && c <= '/uF8FF')     break;    if (c >= '/uFFF0' && c <= '/uFFFF')     break;    sb.append(c);    break;   }  }  return sb.toString(); } /**  * 将字符串中特定模式的字符转换成map中对应的值  *  * @param s  *   需要转换的字符串  * @param map  *   转换所需的键值对集合  * @return 转换后的字符串  */ public static String replace(String s, Map<String, Object> map) {  StringBuilder ret = new StringBuilder((int) (s.length() * 1.5));  int cursor = 0;  for (int start, end; (start = s.indexOf("${", cursor)) != -1 && (end = s.indexOf("}", start)) != -1;) {   ret.append(s.substring(cursor, start)).append(map.get(s.substring(start + 2, end)));   cursor = end + 1;  }  ret.append(s.substring(cursor, s.length()));  return ret.toString(); } public static String replace(String s, Object... objs) {  if (objs == null || objs.length == 0)   return s;  if (s.indexOf("{}") == -1)   return s;  StringBuilder ret = new StringBuilder((int) (s.length() * 1.5));  int cursor = 0;  int index = 0;  for (int start; (start = s.indexOf("{}", cursor)) != -1;) {   ret.append(s.substring(cursor, start));   if (index < objs.length)    ret.append(objs[index]);   else    ret.append("{}");   cursor = start + 2;   index++;  }  ret.append(s.substring(cursor, s.length()));  return ret.toString(); } /**  * 字符串格式化工具,参数必须以{0}之类的样式标示出来.大括号中的数字从0开始。  *   * @param source  *   源字符串  * @param params  *   需要替换的参数列表,写入时会调用每个参数的toString().  * @return 替换完成的字符串。如果原始字符串为空或者参数为空那么将直接返回原始字符串。  */ public static String replaceArgs(String source, Object... params) {  if (params == null || params.length == 0 || source == null || source.isEmpty()) {   return source;  }  StringBuilder buff = new StringBuilder(source);  StringBuilder temp = new StringBuilder();  int startIndex = 0;  int endIndex = 0;  String param = null;  for (int count = 0; count < params.length; count++) {   if (params[count] == null) {    param = null;   } else {    param = params[count].toString();   }   temp.delete(0, temp.length());   temp.append("{");   temp.append(count);   temp.append("}");   while (true) {    startIndex = buff.indexOf(temp.toString(), endIndex);    if (startIndex == -1) {     break;    }    endIndex = startIndex + temp.length();    buff.replace(startIndex, endIndex, param == null ? "" : param);   }   startIndex = 0;   endIndex = 0;  }  return buff.toString(); } public static String substringBefore(final String s, final String separator) {  if (isEmpty(s) || separator == null) {   return s;  }  if (separator.isEmpty()) {   return "";  }  final int pos = s.indexOf(separator);  if (pos < 0) {   return s;  }  return s.substring(0, pos); } public static String substringBetween(final String str, final String open, final String close) {  if (str == null || open == null || close == null) {   return null;  }  final int start = str.indexOf(open);  if (start != -1) {   final int end = str.indexOf(close, start + open.length());   if (end != -1) {    return str.substring(start + open.length(), end);   }  }  return null; } public static String substringAfter(final String str, final String separator) {  if (isEmpty(str)) {   return str;  }  if (separator == null) {   return "";  }  final int pos = str.indexOf(separator);  if (pos == -1) {   return "";  }  return str.substring(pos + separator.length()); } /** * 转换为字节数组 * @param str * @return  */ public static String toString(byte[] bytes){  try {   return new String(bytes, "utf-8");  } catch (UnsupportedEncodingException e) {   return null;  } } /** * 转换为字节数组 * @param str * @return  */ public static byte[] getBytes(String str){  if (str != null){  try {   return str.getBytes("utf-8");   } catch (UnsupportedEncodingException e) {   return null;   }  }else{  return null;  } } public static void main(String[] a){  String escapeXML = escapeXML("//");  System.out.println(escapeXML); }}