• java常用工具类(java技术交流群57388149)


    package com.itjh.javaUtil;
     
    import java.util.ArrayList;
    import java.util.List;
     
    /**
    *
    * String工具类. <br>
    *
    * @author 宋立君
    * @date 2014年06月24日
    */
    public class StringUtil {
     
        private static final int INDEX_NOT_FOUND = -1;
        private static final String EMPTY = "";
        /**
         * <p>
         * The maximum size to which the padding constant(s) can expand.
         * </p>
         */
        private static final int PAD_LIMIT = 8192;
     
        /**
         * 功能:将半角的符号转换成全角符号.(即英文字符转中文字符)
         *
         * @author 宋立君
         * @param str
         *            源字符串
         * @return String
         * @date 2014年06月24日
         */
        public static String changeToFull(String str) {
            String source = "1234567890!@#$%^&*()abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-_=+\|[];:'",<.>/?";
            String[] decode = { "1", "2", "3", "4", "5", "6", "7", "8", "9", "0",
                    "!", "@", "#", "$", "%", "︿", "&", "*", "(", ")", "a", "b",
                    "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n",
                    "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z",
                    "A", "B", "C", "D", "E", "F", "G", "H", "I", "J", "K", "L",
                    "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V", "W", "X",
                    "Y", "Z", "-", "_", "=", "+", "\", "|", "【", "】", ";", ":",
                    "'", """, ",", "〈", "。", "〉", "/", "?" };
            String result = "";
            for (int i = 0; i < str.length(); i++) {
                int pos = source.indexOf(str.charAt(i));
                if (pos != -1) {
                    result += decode[pos];
                } else {
                    result += str.charAt(i);
                }
            }
            return result;
        }
     
        /**
         * 功能:cs串中是否一个都不包含字符数组searchChars中的字符。
         *
         * @author 宋立君
         * @param cs
         *            字符串
         * @param searchChars
         *            字符数组
         * @return boolean 都不包含返回true,否则返回false。
         * @date 2014年06月24日
         */
        public static boolean containsNone(CharSequence cs, char... searchChars) {
            if (cs == null || searchChars == null) {
                return true;
            }
            int csLen = cs.length();
            int csLast = csLen - 1;
            int searchLen = searchChars.length;
            int searchLast = searchLen - 1;
            for (int i = 0; i < csLen; i++) {
                char ch = cs.charAt(i);
                for (int j = 0; j < searchLen; j++) {
                    if (searchChars[j] == ch) {
                        if (Character.isHighSurrogate(ch)) {
                            if (j == searchLast) {
                                // missing low surrogate, fine, like
                                // String.indexOf(String)
                                return false;
                            }
                            if (i < csLast
                                    && searchChars[j + 1] == cs.charAt(i + 1)) {
                                return false;
                            }
                        } else {
                            // ch is in the Basic Multilingual Plane
                            return false;
                        }
                    }
                }
            }
            return true;
        }
     
        /**
         * <p>
         * 编码为Unicode,格式 'u0020'.
         * </p>
         *
         * @author 宋立君
         *
         *         <pre>
         *   CharUtils.unicodeEscaped(' ') = "u0020"
         *   CharUtils.unicodeEscaped('A') = "u0041"
         * </pre>
         *
         * @param ch
         *            源字符串
         * @return 转码后的字符串
         * @date 2014年06月24日
         */
        public static String unicodeEscaped(char ch) {
            if (ch < 0x10) {
                return "\u000" + Integer.toHexString(ch);
            } else if (ch < 0x100) {
                return "\u00" + Integer.toHexString(ch);
            } else if (ch < 0x1000) {
                return "\u0" + Integer.toHexString(ch);
            }
            return "\u" + Integer.toHexString(ch);
        }
     
        /**
         * <p>
         * 进行tostring操作,如果传入的是null,返回空字符串。
         * </p>
         *
         * <pre>
         * ObjectUtils.toString(null)         = ""
         * ObjectUtils.toString("")           = ""
         * ObjectUtils.toString("bat")        = "bat"
         * ObjectUtils.toString(Boolean.TRUE) = "true"
         * </pre>
         *
         * @param obj
         *            源
         * @return String
         */
        public static String toString(Object obj) {
            return obj == null ? "" : obj.toString();
        }
     
        /**
         * <p>
         * 进行tostring操作,如果传入的是null,返回指定的默认值。
         * </p>
         *
         * <pre>
         * ObjectUtils.toString(null, null)           = null
         * ObjectUtils.toString(null, "null")         = "null"
         * ObjectUtils.toString("", "null")           = ""
         * ObjectUtils.toString("bat", "null")        = "bat"
         * ObjectUtils.toString(Boolean.TRUE, "null") = "true"
         * </pre>
         *
         * @param obj
         *            源
         * @param nullStr
         *            如果obj为null时返回这个指定值
         * @return String
         */
        public static String toString(Object obj, String nullStr) {
            return obj == null ? nullStr : obj.toString();
        }
     
        /**
         * <p>
         * 只从源字符串中移除指定开头子字符串.
         * </p>
         *
         * <pre>
         * StringUtil.removeStart(null, *)      = null
         * StringUtil.removeStart("", *)        = ""
         * StringUtil.removeStart(*, null)      = *
         * StringUtil.removeStart("www.domain.com", "www.")   = "domain.com"
         * StringUtil.removeStart("domain.com", "www.")       = "domain.com"
         * StringUtil.removeStart("www.domain.com", "domain") = "www.domain.com"
         * StringUtil.removeStart("abc", "")    = "abc"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param remove
         *            将要被移除的子字符串
         * @return String
         */
        public static String removeStart(String str, String remove) {
            if (isEmpty(str) || isEmpty(remove)) {
                return str;
            }
            if (str.startsWith(remove)) {
                return str.substring(remove.length());
            }
            return str;
        }
     
        /**
         * <p>
         * 只从源字符串中移除指定结尾的子字符串.
         * </p>
         *
         * <pre>
         * StringUtil.removeEnd(null, *)      = null
         * StringUtil.removeEnd("", *)        = ""
         * StringUtil.removeEnd(*, null)      = *
         * StringUtil.removeEnd("www.domain.com", ".com.")  = "www.domain.com"
         * StringUtil.removeEnd("www.domain.com", ".com")   = "www.domain"
         * StringUtil.removeEnd("www.domain.com", "domain") = "www.domain.com"
         * StringUtil.removeEnd("abc", "")    = "abc"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param remove
         *            将要被移除的子字符串
         * @return String
         */
        public static String removeEnd(String str, String remove) {
            if (isEmpty(str) || isEmpty(remove)) {
                return str;
            }
            if (str.endsWith(remove)) {
                return str.substring(0, str.length() - remove.length());
            }
            return str;
        }
     
        /**
         * <p>
         * 将一个字符串重复N次
         * </p>
         *
         * <pre>
         * StringUtil.repeat(null, 2) = null
         * StringUtil.repeat("", 0)   = ""
         * StringUtil.repeat("", 2)   = ""
         * StringUtil.repeat("a", 3)  = "aaa"
         * StringUtil.repeat("ab", 2) = "abab"
         * StringUtil.repeat("a", -2) = ""
         * </pre>
         *
         * @param str
         *            源字符串
         * @param repeat
         *            重复的次数
         * @return String
         */
        public static String repeat(String str, int repeat) {
            // Performance tuned for 2.0 (JDK1.4)
     
            if (str == null) {
                return null;
            }
            if (repeat <= 0) {
                return EMPTY;
            }
            int inputLength = str.length();
            if (repeat == 1 || inputLength == 0) {
                return str;
            }
            if (inputLength == 1 && repeat <= PAD_LIMIT) {
                return repeat(str.charAt(0), repeat);
            }
     
            int outputLength = inputLength * repeat;
            switch (inputLength) {
            case 1:
                return repeat(str.charAt(0), repeat);
            case 2:
                char ch0 = str.charAt(0);
                char ch1 = str.charAt(1);
                char[] output2 = new char[outputLength];
                for (int i = repeat * 2 - 2; i >= 0; i--, i--) {
                    output2[i] = ch0;
                    output2[i + 1] = ch1;
                }
                return new String(output2);
            default:
                StringBuilder buf = new StringBuilder(outputLength);
                for (int i = 0; i < repeat; i++) {
                    buf.append(str);
                }
                return buf.toString();
            }
        }
     
        /**
         * <p>
         * 将一个字符串重复N次,并且中间加上指定的分隔符
         * </p>
         *
         * <pre>
         * StringUtil.repeat(null, null, 2) = null
         * StringUtil.repeat(null, "x", 2)  = null
         * StringUtil.repeat("", null, 0)   = ""
         * StringUtil.repeat("", "", 2)     = ""
         * StringUtil.repeat("", "x", 3)    = "xxx"
         * StringUtil.repeat("?", ", ", 3)  = "?, ?, ?"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param separator
         *            分隔符
         * @param repeat
         *            重复次数
         * @return String
         */
        public static String repeat(String str, String separator, int repeat) {
            if (str == null || separator == null) {
                return repeat(str, repeat);
            } else {
                // given that repeat(String, int) is quite optimized, better to rely
                // on it than try and splice this into it
                String result = repeat(str + separator, repeat);
                return removeEnd(result, separator);
            }
        }
     
        /**
         * <p>
         * 将某个字符重复N次.
         * </p>
         *
         * @param ch
         *            某个字符
         * @param repeat
         *            重复次数
         * @return String
         */
        public static String repeat(char ch, int repeat) {
            char[] buf = new char[repeat];
            for (int i = repeat - 1; i >= 0; i--) {
                buf[i] = ch;
            }
            return new String(buf);
        }
     
        /**
         * <p>
         * 字符串长度达不到指定长度时,在字符串右边补指定的字符.
         * </p>
         *
         * <pre>
         * StringUtil.rightPad(null, *, *)     = null
         * StringUtil.rightPad("", 3, 'z')     = "zzz"
         * StringUtil.rightPad("bat", 3, 'z')  = "bat"
         * StringUtil.rightPad("bat", 5, 'z')  = "batzz"
         * StringUtil.rightPad("bat", 1, 'z')  = "bat"
         * StringUtil.rightPad("bat", -1, 'z') = "bat"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            指定的长度
         * @param padChar
         *            进行补充的字符
         * @return String
         */
        public static String rightPad(String str, int size, char padChar) {
            if (str == null) {
                return null;
            }
            int pads = size - str.length();
            if (pads <= 0) {
                return str; // returns original String when possible
            }
            if (pads > PAD_LIMIT) {
                return rightPad(str, size, String.valueOf(padChar));
            }
            return str.concat(repeat(padChar, pads));
        }
     
        /**
         * <p>
         * 扩大字符串长度,从左边补充指定字符
         * </p>
         *
         * <pre>
         * StringUtil.rightPad(null, *, *)      = null
         * StringUtil.rightPad("", 3, "z")      = "zzz"
         * StringUtil.rightPad("bat", 3, "yz")  = "bat"
         * StringUtil.rightPad("bat", 5, "yz")  = "batyz"
         * StringUtil.rightPad("bat", 8, "yz")  = "batyzyzy"
         * StringUtil.rightPad("bat", 1, "yz")  = "bat"
         * StringUtil.rightPad("bat", -1, "yz") = "bat"
         * StringUtil.rightPad("bat", 5, null)  = "bat  "
         * StringUtil.rightPad("bat", 5, "")    = "bat  "
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            扩大后的长度
         * @param padStr
         *            在右边补充的字符串
         * @return String
         */
        public static String rightPad(String str, int size, String padStr) {
            if (str == null) {
                return null;
            }
            if (isEmpty(padStr)) {
                padStr = " ";
            }
            int padLen = padStr.length();
            int strLen = str.length();
            int pads = size - strLen;
            if (pads <= 0) {
                return str; // returns original String when possible
            }
            if (padLen == 1 && pads <= PAD_LIMIT) {
                return rightPad(str, size, padStr.charAt(0));
            }
     
            if (pads == padLen) {
                return str.concat(padStr);
            } else if (pads < padLen) {
                return str.concat(padStr.substring(0, pads));
            } else {
                char[] padding = new char[pads];
                char[] padChars = padStr.toCharArray();
                for (int i = 0; i < pads; i++) {
                    padding[i] = padChars[i % padLen];
                }
                return str.concat(new String(padding));
            }
        }
     
        /**
         * <p>
         * 扩大字符串长度,从左边补充空格
         * </p>
         *
         * <pre>
         * StringUtil.leftPad(null, *)   = null
         * StringUtil.leftPad("", 3)     = "   "
         * StringUtil.leftPad("bat", 3)  = "bat"
         * StringUtil.leftPad("bat", 5)  = "  bat"
         * StringUtil.leftPad("bat", 1)  = "bat"
         * StringUtil.leftPad("bat", -1) = "bat"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            扩大后的长度
         * @return String
         */
        public static String leftPad(String str, int size) {
            return leftPad(str, size, ' ');
        }
     
        /**
         * <p>
         * 扩大字符串长度,从左边补充指定的字符
         * </p>
         *
         * <pre>
         * StringUtil.leftPad(null, *, *)     = null
         * StringUtil.leftPad("", 3, 'z')     = "zzz"
         * StringUtil.leftPad("bat", 3, 'z')  = "bat"
         * StringUtil.leftPad("bat", 5, 'z')  = "zzbat"
         * StringUtil.leftPad("bat", 1, 'z')  = "bat"
         * StringUtil.leftPad("bat", -1, 'z') = "bat"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            扩大后的长度
         * @param padStr
         *            补充的字符
         * @return String
         */
        public static String leftPad(String str, int size, char padChar) {
            if (str == null) {
                return null;
            }
            int pads = size - str.length();
            if (pads <= 0) {
                return str; // returns original String when possible
            }
            if (pads > PAD_LIMIT) {
                return leftPad(str, size, String.valueOf(padChar));
            }
            return repeat(padChar, pads).concat(str);
        }
     
        /**
         * <p>
         * 扩大字符串长度,从左边补充指定的字符
         * </p>
         *
         * <pre>
         * StringUtil.leftPad(null, *, *)      = null
         * StringUtil.leftPad("", 3, "z")      = "zzz"
         * StringUtil.leftPad("bat", 3, "yz")  = "bat"
         * StringUtil.leftPad("bat", 5, "yz")  = "yzbat"
         * StringUtil.leftPad("bat", 8, "yz")  = "yzyzybat"
         * StringUtil.leftPad("bat", 1, "yz")  = "bat"
         * StringUtil.leftPad("bat", -1, "yz") = "bat"
         * StringUtil.leftPad("bat", 5, null)  = "  bat"
         * StringUtil.leftPad("bat", 5, "")    = "  bat"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            扩大后的长度
         * @param padStr
         *            补充的字符串
         * @return String
         */
        public static String leftPad(String str, int size, String padStr) {
            if (str == null) {
                return null;
            }
            if (isEmpty(padStr)) {
                padStr = " ";
            }
            int padLen = padStr.length();
            int strLen = str.length();
            int pads = size - strLen;
            if (pads <= 0) {
                return str; // returns original String when possible
            }
            if (padLen == 1 && pads <= PAD_LIMIT) {
                return leftPad(str, size, padStr.charAt(0));
            }
     
            if (pads == padLen) {
                return padStr.concat(str);
            } else if (pads < padLen) {
                return padStr.substring(0, pads).concat(str);
            } else {
                char[] padding = new char[pads];
                char[] padChars = padStr.toCharArray();
                for (int i = 0; i < pads; i++) {
                    padding[i] = padChars[i % padLen];
                }
                return new String(padding).concat(str);
            }
        }
     
        /**
         * <p>
         * 扩大字符串长度并将现在的字符串居中,被扩大部分用空格填充。
         * <p>
         *
         * <pre>
         * StringUtil.center(null, *)   = null
         * StringUtil.center("", 4)     = "    "
         * StringUtil.center("ab", -1)  = "ab"
         * StringUtil.center("ab", 4)   = " ab "
         * StringUtil.center("abcd", 2) = "abcd"
         * StringUtil.center("a", 4)    = " a  "
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            扩大后的长度
         * @return String
         */
        public static String center(String str, int size) {
            return center(str, size, ' ');
        }
     
        /**
         * <p>
         * 将字符串长度修改为指定长度,并进行居中显示。
         * </p>
         *
         * <pre>
         * StringUtil.center(null, *, *)     = null
         * StringUtil.center("", 4, ' ')     = "    "
         * StringUtil.center("ab", -1, ' ')  = "ab"
         * StringUtil.center("ab", 4, ' ')   = " ab"
         * StringUtil.center("abcd", 2, ' ') = "abcd"
         * StringUtil.center("a", 4, ' ')    = " a  "
         * StringUtil.center("a", 4, 'y')    = "yayy"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            指定的长度
         * @param padStr
         *            长度不够时补充的字符串
         * @return String
         * @throws IllegalArgumentException
         *             如果被补充字符串为 null或者 empty
         */
        public static String center(String str, int size, char padChar) {
            if (str == null || size <= 0) {
                return str;
            }
            int strLen = str.length();
            int pads = size - strLen;
            if (pads <= 0) {
                return str;
            }
            str = leftPad(str, strLen + pads / 2, padChar);
            str = rightPad(str, size, padChar);
            return str;
        }
     
        /**
         * <p>
         * 将字符串长度修改为指定长度,并进行居中显示。
         * </p>
         *
         * <pre>
         * StringUtil.center(null, *, *)     = null
         * StringUtil.center("", 4, " ")     = "    "
         * StringUtil.center("ab", -1, " ")  = "ab"
         * StringUtil.center("ab", 4, " ")   = " ab"
         * StringUtil.center("abcd", 2, " ") = "abcd"
         * StringUtil.center("a", 4, " ")    = " a  "
         * StringUtil.center("a", 4, "yz")   = "yayz"
         * StringUtil.center("abc", 7, null) = "  abc  "
         * StringUtil.center("abc", 7, "")   = "  abc  "
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            指定的长度
         * @param padStr
         *            长度不够时补充的字符串
         * @return String
         * @throws IllegalArgumentException
         *             如果被补充字符串为 null或者 empty
         */
        public static String center(String str, int size, String padStr) {
            if (str == null || size <= 0) {
                return str;
            }
            if (isEmpty(padStr)) {
                padStr = " ";
            }
            int strLen = str.length();
            int pads = size - strLen;
            if (pads <= 0) {
                return str;
            }
            str = leftPad(str, strLen + pads / 2, padStr);
            str = rightPad(str, size, padStr);
            return str;
        }
     
        /**
         * <p>
         * 检查字符串是否全部为小写.
         * </p>
         *
         * <pre>
         * StringUtil.isAllLowerCase(null)   = false
         * StringUtil.isAllLowerCase("")     = false
         * StringUtil.isAllLowerCase("  ")   = false
         * StringUtil.isAllLowerCase("abc")  = true
         * StringUtil.isAllLowerCase("abC") = false
         * </pre>
         *
         * @param cs
         *            源字符串
         * @return String
         */
        public static boolean isAllLowerCase(String cs) {
            if (cs == null || isEmpty(cs)) {
                return false;
            }
            int sz = cs.length();
            for (int i = 0; i < sz; i++) {
                if (Character.isLowerCase(cs.charAt(i)) == false) {
                    return false;
                }
            }
            return true;
        }
     
        /**
         * <p>
         * 检查是否都是大写.
         * </p>
         *
         * <pre>
         * StringUtil.isAllUpperCase(null)   = false
         * StringUtil.isAllUpperCase("")     = false
         * StringUtil.isAllUpperCase("  ")   = false
         * StringUtil.isAllUpperCase("ABC")  = true
         * StringUtil.isAllUpperCase("aBC") = false
         * </pre>
         *
         * @param cs
         *            源字符串
         * @return String
         */
        public static boolean isAllUpperCase(String cs) {
            if (cs == null || StringUtil.isEmpty(cs)) {
                return false;
            }
            int sz = cs.length();
            for (int i = 0; i < sz; i++) {
                if (Character.isUpperCase(cs.charAt(i)) == false) {
                    return false;
                }
            }
            return true;
        }
     
        /**
         * <p>
         * 反转字符串.
         * </p>
         *
         * <pre>
         * StringUtil.reverse(null)  = null
         * StringUtil.reverse("")    = ""
         * StringUtil.reverse("bat") = "tab"
         * </pre>
         *
         * @param str
         *            源字符串
         * @return String
         */
        public static String reverse(String str) {
            if (str == null) {
                return null;
            }
            return new StringBuilder(str).reverse().toString();
        }
     
        /**
         * <p>
         * 字符串达不到一定长度时在右边补空白.
         * </p>
         *
         * <pre>
         * StringUtil.rightPad(null, *)   = null
         * StringUtil.rightPad("", 3)     = "   "
         * StringUtil.rightPad("bat", 3)  = "bat"
         * StringUtil.rightPad("bat", 5)  = "bat  "
         * StringUtil.rightPad("bat", 1)  = "bat"
         * StringUtil.rightPad("bat", -1) = "bat"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param size
         *            指定的长度
         * @return String
         */
        public static String rightPad(String str, int size) {
            return rightPad(str, size, ' ');
        }
     
        /**
         * 从右边截取字符串.</p>
         *
         * <pre>
         * StringUtil.right(null, *)    = null
         * StringUtil.right(*, -ve)     = ""
         * StringUtil.right("", *)      = ""
         * StringUtil.right("abc", 0)   = ""
         * StringUtil.right("abc", 2)   = "bc"
         * StringUtil.right("abc", 4)   = "abc"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param len
         *            长度
         * @return String
         */
        public static String right(String str, int len) {
            if (str == null) {
                return null;
            }
            if (len < 0) {
                return EMPTY;
            }
            if (str.length() <= len) {
                return str;
            }
            return str.substring(str.length() - len);
        }
     
        /**
         * <p>
         * 截取一个字符串的前几个.
         * </p>
         *
         * <pre>
         * StringUtil.left(null, *)    = null
         * StringUtil.left(*, -ve)     = ""
         * StringUtil.left("", *)      = ""
         * StringUtil.left("abc", 0)   = ""
         * StringUtil.left("abc", 2)   = "ab"
         * StringUtil.left("abc", 4)   = "abc"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param len
         *            截取的长度
         * @return the String
         */
        public static String left(String str, int len) {
            if (str == null) {
                return null;
            }
            if (len < 0) {
                return EMPTY;
            }
            if (str.length() <= len) {
                return str;
            }
            return str.substring(0, len);
        }
     
        /**
         * <p>
         * 得到tag字符串中间的子字符串,只返回第一个匹配项。
         * </p>
         *
         * <pre>
         * StringUtil.substringBetween(null, *)            = null
         * StringUtil.substringBetween("", "")             = ""
         * StringUtil.substringBetween("", "tag")          = null
         * StringUtil.substringBetween("tagabctag", null)  = null
         * StringUtil.substringBetween("tagabctag", "")    = ""
         * StringUtil.substringBetween("tagabctag", "tag") = "abc"
         * </pre>
         *
         * @param str
         *            源字符串。
         * @param tag
         *            标识字符串。
         * @return String 子字符串, 如果没有符合要求的,返回{@code null}。
         */
        public static String substringBetween(String str, String tag) {
            return substringBetween(str, tag, tag);
        }
     
        /**
         * <p>
         * 得到两个字符串中间的子字符串,只返回第一个匹配项。
         * </p>
         *
         * <pre>
         * StringUtil.substringBetween("wx[b]yz", "[", "]") = "b"
         * StringUtil.substringBetween(null, *, *)          = null
         * StringUtil.substringBetween(*, null, *)          = null
         * StringUtil.substringBetween(*, *, null)          = null
         * StringUtil.substringBetween("", "", "")          = ""
         * StringUtil.substringBetween("", "", "]")         = null
         * StringUtil.substringBetween("", "[", "]")        = null
         * StringUtil.substringBetween("yabcz", "", "")     = ""
         * StringUtil.substringBetween("yabcz", "y", "z")   = "abc"
         * StringUtil.substringBetween("yabczyabcz", "y", "z")   = "abc"
         * </pre>
         *
         * @param str
         *            源字符串
         * @param open
         *            起字符串。
         * @param close
         *            末字符串。
         * @return String 子字符串, 如果没有符合要求的,返回{@code null}。
         */
        public static String substringBetween(String str, String open, String close) {
            if (str == null || open == null || close == null) {
                return null;
            }
            int start = str.indexOf(open);
            if (start != INDEX_NOT_FOUND) {
                int end = str.indexOf(close, start + open.length());
                if (end != INDEX_NOT_FOUND) {
                    return str.substring(start + open.length(), end);
                }
            }
            return null;
        }
     
        /**
         * <p>
         * 得到两个字符串中间的子字符串,所有匹配项组合为数组并返回。
         * </p>
         *
         * <pre>
         * StringUtil.substringsBetween("[a][b][c]", "[", "]") = ["a","b","c"]
         * StringUtil.substringsBetween(null, *, *)            = null
         * StringUtil.substringsBetween(*, null, *)            = null
         * StringUtil.substringsBetween(*, *, null)            = null
         * StringUtil.substringsBetween("", "[", "]")          = []
         * </pre>
         *
         * @param str
         *            源字符串
         * @param open
         *            起字符串。
         * @param close
         *            末字符串。
         * @return String 子字符串数组, 如果没有符合要求的,返回{@code null}。
         */
        public static String[] substringsBetween(String str, String open,
                String close) {
            if (str == null || isEmpty(open) || isEmpty(close)) {
                return null;
            }
            int strLen = str.length();
            if (strLen == 0) {
                return new String[0];
            }
            int closeLen = close.length();
            int openLen = open.length();
            List<String> list = new ArrayList<String>();
            int pos = 0;
            while (pos < strLen - closeLen) {
                int start = str.indexOf(open, pos);
                if (start < 0) {
                    break;
                }
                start += openLen;
                int end = str.indexOf(close, start);
                if (end < 0) {
                    break;
                }
                list.add(str.substring(start, end));
                pos = end + closeLen;
            }
            if (list.isEmpty()) {
                return null;
            }
            return list.toArray(new String[list.size()]);
        }
     
        /**
         * 功能:切换字符串中的所有字母大小写。<br/>
         *
         * <pre>
         * StringUtil.swapCase(null)                 = null
         * StringUtil.swapCase("")                   = ""
         * StringUtil.swapCase("The dog has a BONE") = "tHE DOG HAS A bone"
         * </pre>
         *
         *
         * @param str
         *            源字符串
         * @return String
         */
        public static String swapCase(String str) {
            if (StringUtil.isEmpty(str)) {
                return str;
            }
            char[] buffer = str.toCharArray();
     
            boolean whitespace = true;
     
            for (int i = 0; i < buffer.length; i++) {
                char ch = buffer[i];
                if (Character.isUpperCase(ch)) {
                    buffer[i] = Character.toLowerCase(ch);
                    whitespace = false;
                } else if (Character.isTitleCase(ch)) {
                    buffer[i] = Character.toLowerCase(ch);
                    whitespace = false;
                } else if (Character.isLowerCase(ch)) {
                    if (whitespace) {
                        buffer[i] = Character.toTitleCase(ch);
                        whitespace = false;
                    } else {
                        buffer[i] = Character.toUpperCase(ch);
                    }
                } else {
                    whitespace = Character.isWhitespace(ch);
                }
            }
            return new String(buffer);
        }
     
        /**
         * 功能:截取出最后一个标志位之后的字符串.<br/>
         * 如果sourceStr为empty或者expr为null,直接返回源字符串。<br/>
         * 如果expr长度为0,直接返回sourceStr。<br/>
         * 如果expr在sourceStr中不存在,直接返回sourceStr。<br/>
         *
         * @author 宋立君
         * @date 2014年06月24日
         * @param sourceStr
         *            被截取的字符串
         * @param expr
         *            分隔符
         * @return String
         */
        public static String substringAfterLast(String sourceStr, String expr) {
            if (isEmpty(sourceStr) || expr == null) {
                return sourceStr;
            }
            if (expr.length() == 0) {
                return sourceStr;
            }
     
            int pos = sourceStr.lastIndexOf(expr);
            if (pos == -1) {
                return sourceStr;
            }
            return sourceStr.substring(pos + expr.length());
        }
     
        /**
         * 功能:截取出最后一个标志位之前的字符串.<br/>
         * 如果sourceStr为empty或者expr为null,直接返回源字符串。<br/>
         * 如果expr长度为0,直接返回sourceStr。<br/>
         * 如果expr在sourceStr中不存在,直接返回sourceStr。<br/>
         *
         * @author 宋立君
         * @date 2014年06月24日
         * @param sourceStr
         *            被截取的字符串
         * @param expr
         *            分隔符
         * @return String
         */
        public static String substringBeforeLast(String sourceStr, String expr) {
            if (isEmpty(sourceStr) || expr == null) {
                return sourceStr;
            }
            if (expr.length() == 0) {
                return sourceStr;
            }
            int pos = sourceStr.lastIndexOf(expr);
            if (pos == -1) {
                return sourceStr;
            }
            return sourceStr.substring(0, pos);
        }
     
        /**
         * 功能:截取出第一个标志位之后的字符串.<br/>
         * 如果sourceStr为empty或者expr为null,直接返回源字符串。<br/>
         * 如果expr长度为0,直接返回sourceStr。<br/>
         * 如果expr在sourceStr中不存在,直接返回sourceStr。<br/>
         *
         * @author 宋立君
         * @date 2014年06月24日
         * @param sourceStr
         *            被截取的字符串
         * @param expr
         *            分隔符
         * @return String
         */
        public static String substringAfter(String sourceStr, String expr) {
            if (isEmpty(sourceStr) || expr == null) {
                return sourceStr;
            }
            if (expr.length() == 0) {
                return sourceStr;
            }
     
            int pos = sourceStr.indexOf(expr);
            if (pos == -1) {
                return sourceStr;
            }
            return sourceStr.substring(pos + expr.length());
        }
     
        /**
         * 功能:截取出第一个标志位之前的字符串.<br/>
         * 如果sourceStr为empty或者expr为null,直接返回源字符串。<br/>
         * 如果expr长度为0,直接返回sourceStr。<br/>
         * 如果expr在sourceStr中不存在,直接返回sourceStr。<br/>
         * 如果expr在sourceStr中存在不止一个,以第一个位置为准。
         *
         * @author 宋立君
         * @date 2014年06月24日
         * @param sourceStr
         *            被截取的字符串
         * @param expr
         *            分隔符
         * @return String
         */
        public static String substringBefore(String sourceStr, String expr) {
            if (isEmpty(sourceStr) || expr == null) {
                return sourceStr;
            }
            if (expr.length() == 0) {
                return sourceStr;
            }
            int pos = sourceStr.indexOf(expr);
            if (pos == -1) {
                return sourceStr;
            }
            return sourceStr.substring(0, pos);
        }
     
        /**
         * 功能:检查这个字符串是不是空字符串。<br/>
         * 如果这个字符串为null或者trim后为空字符串则返回true,否则返回false。
         *
         * @author 宋立君
         * @date 2014年06月24日
         * @param chkStr
         *            被检查的字符串
         * @return boolean
         */
        public static boolean isEmpty(String chkStr) {
            if (chkStr == null) {
                return true;
            } else {
                return "".equals(chkStr.trim()) ? true : false;
            }
        }
     
        /**
         * 如果字符串没有超过最长显示长度返回原字符串,否则从开头截取指定长度并加...返回。
         *
         * @param str
         *            原字符串
         * @param length
         *            字符串最长显示的长度
         * @return 转换后的字符串
         */
        public static String trimString(String str, int length) {
            if (str == null) {
                return "";
            } else if (str.length() > length) {
                return str.substring(0, length - 3) + "...";
            } else {
                return str;
            }
        }
     
    }

    二、MD5

    三、File工具类

  • 相关阅读:
    Hanlp(汉语言处理包)配置、使用、官方文档
    Mysql 在DOS窗口下的操作
    漂亮的省级下拉选择
    数组的应用排序
    设置外部样式坐标的位置
    动态设置Div坐标
    对联广告
    树形菜单
    隐藏图和图框架
    使用clssneme改变图片或样式
  • 原文地址:https://www.cnblogs.com/Nbge/p/3811680.html
Copyright © 2020-2023  润新知