自定义封装StringUtils常用工具类

                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 list = new ArrayList();
        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 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);
    }
}