Java中常用String处理函数集合
2011-10-08 10:11
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/**
* 字符串操作通用类
*
* @author
* @version
*/
public class StringUtil {
/**
* The empty String {@code ""}.
*/
public static final String EMPTY = "";
// 字符串常量枚举
public static enum REGEX_ENUM {
EMAIL("^\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$"), CHINESE_CHARACTER(
"[\\u4E00-\\u9FA5]+");
private String value;
private REGEX_ENUM(String value) {
this.value = value;
}
public String toString() {
return this.value;
}
};
/**
* 检查字符串str是否匹配正则表达式regex
*
* @param regex
* @param str
* @return
*/
public static boolean matcherRegex(String regex, String str) {
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(str);
return matcher.matches();
}
/**
* 是否为汉字
*
* @param ch
* @return
*/
public static boolean isChineseCharacter(char ch) {
return matcherRegex(REGEX_ENUM.CHINESE_CHARACTER.toString(),
String.valueOf(ch));
}
/**
* 按字节截取字符串
*
* @param str
* 要截取的字符串
* @param byteLength
* 长度
* @return 结果字符串
*/
public static String subString(String str, int byteLength) {
if (isBlank(str))
return EMPTY;
if (str.getBytes().length <= byteLength)
return str;
if (str.length() >= byteLength)
str = str.substring(0, byteLength);
int readLen = 0;
String c = null;
StringBuffer sb = new StringBuffer(EMPTY);
for (int i = 0; i < str.length(); i++) {
c = String.valueOf(str.charAt(i));
readLen += c.getBytes().length;
if (readLen > byteLength)
return sb.toString();
sb.append(c);
}
return sb.toString();
}
/**
* check length (minLength<=str.length<=maxLength)
*
* @param str
* input String
* @param minLength
* minute length
* @param maxLength
* maximum length
* @return boolean true: minLength<=str.length<=maxLength false: other
*/
public static boolean checkLength(String str, int minLength, int maxLength) {
if (isBlank(str))
return false;
int len = str.length();
if (minLength == 0)
return len <= maxLength;
else if (maxLength == 0)
return len >= minLength;
else
return (len >= minLength && len <= maxLength);
}
/**
* decode string by UTF-8
*
* @param str
* input string
* @return String decode string
*/
public static String decodeString(String str) {
return decodeString(str, "UTF-8");
}
/**
* decode string by the input encoding
*
* @param str
* @param encoding
* @return
*/
public static String decodeString(String str, String encoding) {
if (isBlank(str))
return EMPTY;
try {
return URLDecoder.decode(str.trim(), encoding);
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* decode the string
*
* @param str
* @param encoding
* @return
*/
public static String decodeURI(String str) {
if (isBlank(str))
return EMPTY;
try {
return new String(str.getBytes("ISO8859-1"), "UTF-8");
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* encode String by UTF-8
*
* @param str
* input string
* @return String
*/
public static String encodeString(String str) {
return encodeString(str, "UTF-8");
}
/**
* encode String by the input encoding
*
* @param str
* input string
* @return String encode string
*/
public static String encodeString(String str, String encoding) {
if (isBlank(str))
return EMPTY;
try {
return URLEncoder.encode(str.trim(), encoding);
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* get the only string by time
*
* @return
*/
public static String getOnlyString() {
return String.valueOf(System.currentTimeMillis());
}
/**
* <p>
* Checks if a CharSequence is whitespace, empty ("") or null.
* </p>
*
* <pre>
* StringUtils.isBlank(null) = true
* StringUtils.isBlank("") = true
* StringUtils.isBlank(" ") = true
* StringUtils.isBlank("bob") = false
* StringUtils.isBlank(" bob ") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is null, empty or whitespace
*/
public static boolean isBlank(CharSequence cs) {
int strLen;
if (cs == null || (strLen = cs.length()) == 0) {
return true;
}
for (int i = 0; i < strLen; i++) {
if ((Character.isWhitespace(cs.charAt(i)) == false)) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if a CharSequence is not empty (""), not null and not whitespace
* only.
* </p>
*
* <pre>
* StringUtils.isNotBlank(null) = false
* StringUtils.isNotBlank("") = false
* StringUtils.isNotBlank(" ") = false
* StringUtils.isNotBlank("bob") = true
* StringUtils.isNotBlank(" bob ") = true
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is not empty and not null and
* not whitespace
*/
public static boolean isNotBlank(CharSequence cs) {
return !StringUtil.isBlank(cs);
}
/**
* parses the specified string as a signed decimal integer value
*
* @param str
* input string representation of an integer value.
* @return boolean true: each character is integer false: other
*/
public static boolean isInteger(String str) {
if (isBlank(str))
return false;
try {
Integer.parseInt(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* parses the specified string as a signed decimal long value
*
* @param str
* input string representation of an integer value.
* @return boolean true: each character is long integer false: other
*/
public static boolean isLong(String str) {
if (isBlank(str))
return false;
try {
Long.parseLong(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* parses the specified string as a signed boolean value
*
* @param str
* input string
* @return boolean true: str = true / TRUE (Ignore upper case or low case)
* false: other
*/
public static boolean isBoolean(String str) {
if (isBlank(str))
return false;
try {
Boolean.parseBoolean(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the specified string as a double value
*
* @param str
* @return
*/
public static boolean isDouble(String str) {
if (isBlank(str))
return false;
try {
Double.parseDouble(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the specified string as a Date value
*
* @param str
* the input string
* @return boolean str为时间型返回true，否则返回false
*/
public static boolean isDate(String str) {
if (isBlank(str))
return false;
try {
java.sql.Date.valueOf(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the string arrays is all long values
*
* @param str
* the input string array
* @return boolean str为长整型数组返回true，否则返回false
*/
public static boolean isLongs(String str[]) {
for (int i = 0; i < str.length; i++) {
if (!isLong(str[i]))
return false;
}
return true;
}
/**
* 检查字符串数组str是否为整型数组
*
* @param str
* 要检查的字符串
* @return boolean str为整型数组返回true，否则返回false
*/
public static boolean isIntegers(String str[]) {
for (int i = 0; i < str.length; i++)
if (!isInteger(str[i]))
return false;
return true;
}
/**
* 检查字符串数组str是否为布尔型数组
*
* @param str
* 要检查的字符串
* @return boolean str为布尔型数组返回true，否则返回false
*/
public static boolean isBooleans(String str[]) {
for (int i = 0; i < str.length; i++)
if (!isBoolean(str[i]))
return false;
return true;
}
/**
* 检查字符串str是否为时间
*
* @param str
* 要检查的字符串
* @return str为时间型返回true，否则返回false
*/
public static boolean isTimestamp(String str) {
if (isBlank(str))
return false;
try {
java.sql.Date.valueOf(str.trim());
return true;
} catch (Exception ex) {
}
return false;
}
/**
* 检查字符串str是否为(yyyy-MM-dd HH:mm:ss)模式的时间
*
* @param str
* 要检查的字符串
* @return str为时间型返回true，否则返回false
*/
public static boolean isFullTimestamp(String str) {
if (isBlank(str))
return false;
try {
SimpleDateFormat format = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss");
Date date = format.parse(str.trim());
return date != null;
} catch (Exception e) {
}
return false;
}
/**
* 将字符数组转换为长整型数组
*
* @param str
* 字符数组
* @return Long[] 长整型数组
*/
public static Long[] stringsToLongs(String str[]) {
Long lon[] = new Long[str.length];
for (int i = 0; i < lon.length; i++)
lon[i] = new Long(str[i]);
return lon;
}
/**
* 将字符数组转换为整型数组
*
* @param str
* 字符数组
* @return Integer[] 整型数组
*/
public static Integer[] stringsToIntegers(String str[]) {
Integer array[] = new Integer[str.length];
for (int i = 0; i < array.length; i++)
array[i] = new Integer(str[i]);
return array;
}
/**
* 将字符数组转换为布尔型数组
*
* @param str
* 字符数组
* @return Boolean[] 布尔型数组
*/
public static Boolean[] stringsToBooleans(String str[]) {
Boolean array[] = new Boolean[str.length];
for (int i = 0; i < array.length; i++)
array[i] = new Boolean(str[i]);
return array;
}
/**
* 将字符数组转换为浮点型数组
*
* @param str
* 字符数组
* @return double[] 浮点型数组
*/
public static double[] stringsToDoubles(String str[]) {
double array[] = new double[str.length];
for (int i = 0; i < array.length; i++)
array[i] = Double.parseDouble(str[i]);
return array;
}
/**
* 得到数字格式化后的字符串
*
* @param number
* Number类型
* @param minFractionDigits
* 小数最小位数
* @param maxFractionDigits
* 小数最大位数
* @return String 格式化后的字符串
*/
public static String formatNumber(Number number, int minFractionDigits,
int maxFractionDigits) {
NumberFormat format = NumberFormat.getInstance();
format.setMinimumFractionDigits(minFractionDigits);
format.setMaximumFractionDigits(maxFractionDigits);
return format.format(number);
}
/**
* 字符串高亮<br>
* 解决了高亮前缀或高亮后缀在要高亮显示的字符串数组在存在时的问题，根据本算法可解决JS高亮显示时相同的问题
*
* @param text
* 内容
* @param replaceStrs
* 要高亮显示的字符串数组
* @param beginStr
* 高亮前缀，如<font color=red>
* @param endStr
* 高亮后缀，如</font>
* @return
*/
public static String heightLight(String text, String[] replaceStrs,
String beginStr, String endStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(heightLight(beforeStr, replaceStrs, beginStr,
endStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(beginStr).append(replaceStr).append(endStr);
str.append(heightLight(afterStr, replaceStrs, beginStr, endStr));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串数组为一个字符串<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStrs
* @param newStr
* @return
*/
public static String replaceAll(String text, String[] replaceStrs,
String newStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAll(beforeStr, replaceStrs, newStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStr);
str.append(replaceAll(afterStr, replaceStrs, newStr));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串为一个字符串<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStr
* @param newStr
* @return
*/
public static String replaceAll(String text, String replaceStr,
String newStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAll(beforeStr, replaceStr, newStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStr);
str.append(replaceAll(afterStr, replaceStr, newStr));
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串数组为一个字符串数组<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStrs
* @param newStrs
* @return
*/
public static String replaceAllArray(String text, String[] replaceStrs,
String[] newStrs) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAllArray(beforeStr, replaceStrs, newStrs));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStrs[i]);
str.append(replaceAllArray(afterStr, replaceStrs, newStrs));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 解码HTML(将>,<,",&转换成>,<,",& )
*
* @param html
* @return
*/
public static String decodeHTML(String html) {
if (isBlank(html))
return EMPTY;
String[] replaceStr = { "&", "<", ">", """ };
String[] newStr = { "&", "<", ">", "\"" };
return replaceAllArray(html, replaceStr, newStr);
}
/**
* 编码HTML(将>,<,",&
* 转换成>,<,",&)(高效率，来自FreeMarker模板源码，比replaceAll速度快很多)
*
* @param html
* @return
*/
public static String encodeHTML(String html) {
if (isBlank(html))
return EMPTY;
int ln = html.length();
char c;
StringBuffer b;
for (int i = 0; i < ln; i++) {
c = html.charAt(i);
if (c == '<' || c == '>' || c == '&' || c == '"') {
b = new StringBuffer(html.substring(0, i));
switch (c) {
case '<':
b.append("<");
break;
case '>':
b.append(">");
break;
case '&':
b.append("&");
break;
case '"':
b.append(""");
break;
}
i++;
int next = i;
while (i < ln) {
c = html.charAt(i);
if (c == '<' || c == '>' || c == '&' || c == '"') {
b.append(html.substring(next, i));
switch (c) {
case '<':
b.append("<");
break;
case '>':
b.append(">");
break;
case '&':
b.append("&");
break;
case '"':
b.append(""");
break;
}
next = i + 1;
}
i++;
}
if (next < ln)
b.append(html.substring(next));
html = b.toString();
break;
}
}
return html;
}
/**
* MD5加密
*
* @param plainText
* 要加密的字符串
* @return 加密后的字符串
*/
public static String Md5(String plainText) {
StringBuffer buf = new StringBuffer(EMPTY);
try {
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(plainText.getBytes());
byte b[] = md.digest();
int i = 0;
for (int offset = 0; offset < b.length; offset++) {
i = b[offset];
if (i < 0)
i += 256;
if (i < 16)
buf.append("0");
buf.append(Integer.toHexString(i));
}
} catch (Exception e) {
e.printStackTrace();
}
return buf.toString();
}
/**
* MD5加密(32)
*
* @param plainText
* 要加密的字符串
* @return
*/
public final static String MD5(String plainText) {
char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f' };
try {
byte[] strTemp = plainText.getBytes();
MessageDigest mdTemp = MessageDigest.getInstance("MD5");
mdTemp.update(strTemp);
byte[] md = mdTemp.digest();
int j = md.length;
char str[] = new char[j * 2];
int k = 0;
for (int i = 0; i < j; i++) {
byte byte0 = md[i];
str[k++] = hexDigits[byte0 >>> 4 & 0xf];
str[k++] = hexDigits[byte0 & 0xf];
}
return new String(str);
} catch (Exception e) {
}
return "";
}
// Empty checks
// -----------------------------------------------------------------------
/**
* <p>
* Checks if a CharSequence is empty ("") or null.
* </p>
*
* <pre>
* StringUtils.isEmpty(null) = true
* StringUtils.isEmpty("") = true
* StringUtils.isEmpty(" ") = false
* StringUtils.isEmpty("bob") = false
* StringUtils.isEmpty(" bob ") = false
* </pre>
*
* <p>
* NOTE: This method changed in Lang version 2.0. It no longer trims the
* CharSequence. That functionality is available in isBlank().
* </p>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is empty or null
*/
public static boolean isEmpty(CharSequence cs) {
return cs == null || cs.length() == 0;
}
/**
* <p>
* Checks if a CharSequence is not empty ("") and not null.
* </p>
*
* <pre>
* StringUtils.isNotEmpty(null) = false
* StringUtils.isNotEmpty("") = false
* StringUtils.isNotEmpty(" ") = true
* StringUtils.isNotEmpty("bob") = true
* StringUtils.isNotEmpty(" bob ") = true
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is not empty and not null
* @since 3.0 Changed signature from isNotEmpty(String) to
* isNotEmpty(CharSequence)
*/
public static boolean isNotEmpty(CharSequence cs) {
return !isEmpty(cs);
}
// Trim
// -----------------------------------------------------------------------
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String,
* handling {@code null} by returning {@code null}.
* </p>
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use {@link #strip(String)}.
* </p>
*
* <p>
* To trim your choice of characters, use the {@link #strip(String, String)}
* methods.
* </p>
*
* <pre>
* StringUtils.trim(null) = null
* StringUtils.trim("") = ""
* StringUtils.trim(" ") = ""
* StringUtils.trim("abc") = "abc"
* StringUtils.trim(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed string, {@code null} if null String input
*/
public static String trim(String str) {
return str == null ? null : str.trim();
}
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String
* returning {@code null} if the String is empty ("") after the trim or if
* it is {@code null}.
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use
* {@link #stripToNull(String)}.
* </p>
*
* <pre>
* StringUtils.trimToNull(null) = null
* StringUtils.trimToNull("") = null
* StringUtils.trimToNull(" ") = null
* StringUtils.trimToNull("abc") = "abc"
* StringUtils.trimToNull(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed String, {@code null} if only chars <= 32, empty or
* null String input
*/
public static String trimToNull(String str) {
String ts = trim(str);
return isEmpty(ts) ? null : ts;
}
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String
* returning an empty String ("") if the String is empty ("") after the trim
* or if it is {@code null}.
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use
* {@link #stripToEmpty(String)}.
* </p>
*
* <pre>
* StringUtils.trimToEmpty(null) = ""
* StringUtils.trimToEmpty("") = ""
* StringUtils.trimToEmpty(" ") = ""
* StringUtils.trimToEmpty("abc") = "abc"
* StringUtils.trimToEmpty(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed String, or an empty String if {@code null} input
*/
public static String trimToEmpty(String str) {
return str == null ? EMPTY : str.trim();
}
// Equals
// -----------------------------------------------------------------------
/**
* <p>
* Compares two CharSequences, returning {@code true} if they are equal.
* </p>
*
* <p>
* {@code null}s are handled without exceptions. Two {@code null} references
* are considered to be equal. The comparison is case sensitive.
* </p>
*
* <pre>
* StringUtils.equals(null, null) = true
* StringUtils.equals(null, "abc") = false
* StringUtils.equals("abc", null) = false
* StringUtils.equals("abc", "abc") = true
* StringUtils.equals("abc", "ABC") = false
* </pre>
*
* @see java.lang.String#equals(Object)
* @param cs1
* the first CharSequence, may be null
* @param cs2
* the second CharSequence, may be null
* @return {@code true} if the CharSequences are equal, case sensitive, or
* both {@code null}
*/
public static boolean equals(CharSequence cs1, CharSequence cs2) {
return cs1 == null ? cs2 == null : cs1.equals(cs2);
}
/**
* <p>
* Compares two CharSequences, returning {@code true} if they are equal
* ignoring the case.
* </p>
*
* <p>
* {@code null}s are handled without exceptions. Two {@code null} references
* are considered equal. Comparison is case insensitive.
* </p>
*
* <pre>
* StringUtils.equalsIgnoreCase(null, null) = true
* StringUtils.equalsIgnoreCase(null, "abc") = false
* StringUtils.equalsIgnoreCase("abc", null) = false
* StringUtils.equalsIgnoreCase("abc", "abc") = true
* StringUtils.equalsIgnoreCase("abc", "ABC") = true
* </pre>
*
* @param str1
* the first CharSequence, may be null
* @param str2
* the second CharSequence, may be null
* @return {@code true} if the CharSequence are equal, case insensitive, or
* both {@code null}
*/
public static boolean equalsIgnoreCase(CharSequence str1, CharSequence str2) {
if (str1 == null || str2 == null) {
return str1 == str2;
} else {
return CharSequenceUtils.regionMatches(str1, true, 0, str2, 0,
Math.max(str1.length(), str2.length()));
}
}
// Case conversion
// -----------------------------------------------------------------------
/**
* <p>
* Converts a String to upper case as per {@link String#toUpperCase()}.
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.upperCase(null) = null
* StringUtils.upperCase("") = ""
* StringUtils.upperCase("aBc") = "ABC"
* </pre>
*
* <p>
* <strong>Note:</strong> As described in the documentation for
* {@link String#toUpperCase()}, the result of this method is affected by
* the current locale. For platform-independent case transformations, the
* method {@link #lowerCase(String, Locale)} should be used with a specific
* locale (e.g. {@link Locale#ENGLISH}).
* </p>
*
* @param str
* the String to upper case, may be null
* @return the upper cased String, {@code null} if null String input
*/
public static String upperCase(String str) {
if (str == null) {
return null;
}
return str.toUpperCase();
}
/**
* <p>
* Converts a String to upper case as per {@link String#toUpperCase(Locale)}
* .
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.upperCase(null, Locale.ENGLISH) = null
* StringUtils.upperCase("", Locale.ENGLISH) = ""
* StringUtils.upperCase("aBc", Locale.ENGLISH) = "ABC"
* </pre>
*
* @param str
* the String to upper case, may be null
* @param locale
* the locale that defines the case transformation rules, must
* not be null
* @return the upper cased String, {@code null} if null String input
*/
public static String upperCase(String str, Locale locale) {
if (str == null) {
return null;
}
return str.toUpperCase(locale);
}
/**
* <p>
* Converts a String to lower case as per {@link String#toLowerCase()}.
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.lowerCase(null) = null
* StringUtils.lowerCase("") = ""
* StringUtils.lowerCase("aBc") = "abc"
* </pre>
*
* <p>
* <strong>Note:</strong> As described in the documentation for
* {@link String#toLowerCase()}, the result of this method is affected by
* the current locale. For platform-independent case transformations, the
* method {@link #lowerCase(String, Locale)} should be used with a specific
* locale (e.g. {@link Locale#ENGLISH}).
* </p>
*
* @param str
* the String to lower case, may be null
* @return the lower cased String, {@code null} if null String input
*/
public static String lowerCase(String str) {
if (str == null) {
return null;
}
return str.toLowerCase();
}
/**
* <p>
* Converts a String to lower case as per {@link String#toLowerCase(Locale)}
* .
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.lowerCase(null, Locale.ENGLISH) = null
* StringUtils.lowerCase("", Locale.ENGLISH) = ""
* StringUtils.lowerCase("aBc", Locale.ENGLISH) = "abc"
* </pre>
*
* @param str
* the String to lower case, may be null
* @param locale
* the locale that defines the case transformation rules, must
* not be null
* @return the lower cased String, {@code null} if null String input
*/
public static String lowerCase(String str, Locale locale) {
if (str == null) {
return null;
}
return str.toLowerCase(locale);
}
/**
* <p>
* Checks if the CharSequence contains only lowercase characters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAllLowerCase(null) = false
* StringUtils.isAllLowerCase("") = false
* StringUtils.isAllLowerCase(" ") = false
* StringUtils.isAllLowerCase("abc") = true
* StringUtils.isAllLowerCase("abC") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains lowercase characters, and is
* non-null
*/
public static boolean isAllLowerCase(CharSequence 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>
* Checks if the CharSequence contains only uppercase characters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty String (length()=0) will
* return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAllUpperCase(null) = false
* StringUtils.isAllUpperCase("") = false
* StringUtils.isAllUpperCase(" ") = false
* StringUtils.isAllUpperCase("ABC") = true
* StringUtils.isAllUpperCase("aBC") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains uppercase characters, and is
* non-null
*/
public static boolean isAllUpperCase(CharSequence cs) {
if (cs == null || 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;
}
// Defaults
// -----------------------------------------------------------------------
/**
* <p>
* Returns either the passed in String, or if the String is {@code null}, an
* empty String ("").
* </p>
*
* <pre>
* StringUtils.defaultString(null) = ""
* StringUtils.defaultString("") = ""
* StringUtils.defaultString("bat") = "bat"
* </pre>
*
* @see ObjectUtils#toString(Object)
* @see String#valueOf(Object)
* @param str
* the String to check, may be null
* @return the passed in String, or the empty String if it was {@code null}
*/
public static String defaultString(String str) {
return str == null ? EMPTY : str;
}
/**
* <p>
* Returns either the passed in String, or if the String is {@code null},
* the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultString(null, "NULL") = "NULL"
* StringUtils.defaultString("", "NULL") = ""
* StringUtils.defaultString("bat", "NULL") = "bat"
* </pre>
*
* @see ObjectUtils#toString(Object,String)
* @see String#valueOf(Object)
* @param str
* the String to check, may be null
* @param defaultStr
* the default String to return if the input is {@code null}, may
* be null
* @return the passed in String, or the default if it was {@code null}
*/
public static String defaultString(String str, String defaultStr) {
return str == null ? defaultStr : str;
}
/**
* <p>
* Returns either the passed in CharSequence, or if the CharSequence is
* whitespace, empty ("") or {@code null}, the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultIfBlank(null, "NULL") = "NULL"
* StringUtils.defaultIfBlank("", "NULL") = "NULL"
* StringUtils.defaultIfBlank(" ", "NULL") = "NULL"
* StringUtils.defaultIfBlank("bat", "NULL") = "bat"
* StringUtils.defaultIfBlank("", null) = null
* </pre>
*
* @param <T>
* the specific kind of CharSequence
* @param str
* the CharSequence to check, may be null
* @param defaultStr
* the default CharSequence to return if the input is whitespace,
* empty ("") or {@code null}, may be null
* @return the passed in CharSequence, or the default
* @see StringUtils#defaultString(String, String)
*/
public static <T extends CharSequence> T defaultIfBlank(T str, T defaultStr) {
return isBlank(str) ? defaultStr : str;
}
/**
* <p>
* Returns either the passed in CharSequence, or if the CharSequence is
* empty or {@code null}, the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultIfEmpty(null, "NULL") = "NULL"
* StringUtils.defaultIfEmpty("", "NULL") = "NULL"
* StringUtils.defaultIfEmpty("bat", "NULL") = "bat"
* StringUtils.defaultIfEmpty("", null) = null
* </pre>
*
* @param <T>
* the specific kind of CharSequence
* @param str
* the CharSequence to check, may be null
* @param defaultStr
* the default CharSequence to return if the input is empty ("")
* or {@code null}, may be null
* @return the passed in CharSequence, or the default
* @see StringUtils#defaultString(String, String)
*/
public static <T extends CharSequence> T defaultIfEmpty(T str, T defaultStr) {
return isEmpty(str) ? defaultStr : str;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAlpha(null) = false
* StringUtils.isAlpha("") = false
* StringUtils.isAlpha(" ") = false
* StringUtils.isAlpha("abc") = true
* StringUtils.isAlpha("ab2c") = false
* StringUtils.isAlpha("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters, and is non-null
*/
public static boolean isAlpha(CharSequence cs) {
if (cs == null || cs.length() == 0) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetter(cs.charAt(i)) == false) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters and space (' ').
* </p>
*
* <p>
* {@code null} will return {@code false} An empty CharSequence (length()=0)
* will return {@code true}.
* </p>
*
* <pre>
* StringUtils.isAlphaSpace(null) = false
* StringUtils.isAlphaSpace("") = true
* StringUtils.isAlphaSpace(" ") = true
* StringUtils.isAlphaSpace("abc") = true
* StringUtils.isAlphaSpace("ab c") = true
* StringUtils.isAlphaSpace("ab2c") = false
* StringUtils.isAlphaSpace("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters and space, and is non-null
*/
public static boolean isAlphaSpace(CharSequence cs) {
if (cs == null) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetter(cs.charAt(i)) == false)
&& (cs.charAt(i) != ' ')) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters or digits.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAlphanumeric(null) = false
* StringUtils.isAlphanumeric("") = false
* StringUtils.isAlphanumeric(" ") = false
* StringUtils.isAlphanumeric("abc") = true
* StringUtils.isAlphanumeric("ab c") = false
* StringUtils.isAlphanumeric("ab2c") = true
* StringUtils.isAlphanumeric("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters or digits, and is non-null
*/
public static boolean isAlphanumeric(CharSequence cs) {
if (cs == null || cs.length() == 0) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetterOrDigit(cs.charAt(i)) == false) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters, digits or space
* ({@code ' '}).
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code true}.
* </p>
*
* <pre>
* StringUtils.isAlphanumericSpace(null) = false
* StringUtils.isAlphanumericSpace("") = true
* StringUtils.isAlphanumericSpace(" ") = true
* StringUtils.isAlphanumericSpace("abc") = true
* StringUtils.isAlphanumericSpace("ab c") = true
* StringUtils.isAlphanumericSpace("ab2c") = true
* StringUtils.isAlphanumericSpace("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters, digits or space, and is
* non-null
*/
public static boolean isAlphanumericSpace(CharSequence cs) {
if (cs == null) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetterOrDigit(cs.charAt(i)) == false)
&& (cs.charAt(i) != ' ')) {
return false;
}
}
return true;
}
public static boolean isDigit(char ch){
if (ch >= '0' && ch <= '9')
return true;
return false;
}
public static boolean isDigit(int ch){
if (ch >= 0 && ch <= 9)
return true;
return false;
}
}
* 字符串操作通用类
*
* @author
* @version
*/
public class StringUtil {
/**
* The empty String {@code ""}.
*/
public static final String EMPTY = "";
// 字符串常量枚举
public static enum REGEX_ENUM {
EMAIL("^\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*$"), CHINESE_CHARACTER(
"[\\u4E00-\\u9FA5]+");
private String value;
private REGEX_ENUM(String value) {
this.value = value;
}
public String toString() {
return this.value;
}
};
/**
* 检查字符串str是否匹配正则表达式regex
*
* @param regex
* @param str
* @return
*/
public static boolean matcherRegex(String regex, String str) {
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(str);
return matcher.matches();
}
/**
* 是否为汉字
*
* @param ch
* @return
*/
public static boolean isChineseCharacter(char ch) {
return matcherRegex(REGEX_ENUM.CHINESE_CHARACTER.toString(),
String.valueOf(ch));
}
/**
* 按字节截取字符串
*
* @param str
* 要截取的字符串
* @param byteLength
* 长度
* @return 结果字符串
*/
public static String subString(String str, int byteLength) {
if (isBlank(str))
return EMPTY;
if (str.getBytes().length <= byteLength)
return str;
if (str.length() >= byteLength)
str = str.substring(0, byteLength);
int readLen = 0;
String c = null;
StringBuffer sb = new StringBuffer(EMPTY);
for (int i = 0; i < str.length(); i++) {
c = String.valueOf(str.charAt(i));
readLen += c.getBytes().length;
if (readLen > byteLength)
return sb.toString();
sb.append(c);
}
return sb.toString();
}
/**
* check length (minLength<=str.length<=maxLength)
*
* @param str
* input String
* @param minLength
* minute length
* @param maxLength
* maximum length
* @return boolean true: minLength<=str.length<=maxLength false: other
*/
public static boolean checkLength(String str, int minLength, int maxLength) {
if (isBlank(str))
return false;
int len = str.length();
if (minLength == 0)
return len <= maxLength;
else if (maxLength == 0)
return len >= minLength;
else
return (len >= minLength && len <= maxLength);
}
/**
* decode string by UTF-8
*
* @param str
* input string
* @return String decode string
*/
public static String decodeString(String str) {
return decodeString(str, "UTF-8");
}
/**
* decode string by the input encoding
*
* @param str
* @param encoding
* @return
*/
public static String decodeString(String str, String encoding) {
if (isBlank(str))
return EMPTY;
try {
return URLDecoder.decode(str.trim(), encoding);
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* decode the string
*
* @param str
* @param encoding
* @return
*/
public static String decodeURI(String str) {
if (isBlank(str))
return EMPTY;
try {
return new String(str.getBytes("ISO8859-1"), "UTF-8");
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* encode String by UTF-8
*
* @param str
* input string
* @return String
*/
public static String encodeString(String str) {
return encodeString(str, "UTF-8");
}
/**
* encode String by the input encoding
*
* @param str
* input string
* @return String encode string
*/
public static String encodeString(String str, String encoding) {
if (isBlank(str))
return EMPTY;
try {
return URLEncoder.encode(str.trim(), encoding);
} catch (UnsupportedEncodingException e) {
}
return EMPTY;
}
/**
* get the only string by time
*
* @return
*/
public static String getOnlyString() {
return String.valueOf(System.currentTimeMillis());
}
/**
* <p>
* Checks if a CharSequence is whitespace, empty ("") or null.
* </p>
*
* <pre>
* StringUtils.isBlank(null) = true
* StringUtils.isBlank("") = true
* StringUtils.isBlank(" ") = true
* StringUtils.isBlank("bob") = false
* StringUtils.isBlank(" bob ") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is null, empty or whitespace
*/
public static boolean isBlank(CharSequence cs) {
int strLen;
if (cs == null || (strLen = cs.length()) == 0) {
return true;
}
for (int i = 0; i < strLen; i++) {
if ((Character.isWhitespace(cs.charAt(i)) == false)) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if a CharSequence is not empty (""), not null and not whitespace
* only.
* </p>
*
* <pre>
* StringUtils.isNotBlank(null) = false
* StringUtils.isNotBlank("") = false
* StringUtils.isNotBlank(" ") = false
* StringUtils.isNotBlank("bob") = true
* StringUtils.isNotBlank(" bob ") = true
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is not empty and not null and
* not whitespace
*/
public static boolean isNotBlank(CharSequence cs) {
return !StringUtil.isBlank(cs);
}
/**
* parses the specified string as a signed decimal integer value
*
* @param str
* input string representation of an integer value.
* @return boolean true: each character is integer false: other
*/
public static boolean isInteger(String str) {
if (isBlank(str))
return false;
try {
Integer.parseInt(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* parses the specified string as a signed decimal long value
*
* @param str
* input string representation of an integer value.
* @return boolean true: each character is long integer false: other
*/
public static boolean isLong(String str) {
if (isBlank(str))
return false;
try {
Long.parseLong(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* parses the specified string as a signed boolean value
*
* @param str
* input string
* @return boolean true: str = true / TRUE (Ignore upper case or low case)
* false: other
*/
public static boolean isBoolean(String str) {
if (isBlank(str))
return false;
try {
Boolean.parseBoolean(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the specified string as a double value
*
* @param str
* @return
*/
public static boolean isDouble(String str) {
if (isBlank(str))
return false;
try {
Double.parseDouble(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the specified string as a Date value
*
* @param str
* the input string
* @return boolean str为时间型返回true，否则返回false
*/
public static boolean isDate(String str) {
if (isBlank(str))
return false;
try {
java.sql.Date.valueOf(str.trim());
return true;
} catch (Exception e) {
}
return false;
}
/**
* checks the string arrays is all long values
*
* @param str
* the input string array
* @return boolean str为长整型数组返回true，否则返回false
*/
public static boolean isLongs(String str[]) {
for (int i = 0; i < str.length; i++) {
if (!isLong(str[i]))
return false;
}
return true;
}
/**
* 检查字符串数组str是否为整型数组
*
* @param str
* 要检查的字符串
* @return boolean str为整型数组返回true，否则返回false
*/
public static boolean isIntegers(String str[]) {
for (int i = 0; i < str.length; i++)
if (!isInteger(str[i]))
return false;
return true;
}
/**
* 检查字符串数组str是否为布尔型数组
*
* @param str
* 要检查的字符串
* @return boolean str为布尔型数组返回true，否则返回false
*/
public static boolean isBooleans(String str[]) {
for (int i = 0; i < str.length; i++)
if (!isBoolean(str[i]))
return false;
return true;
}
/**
* 检查字符串str是否为时间
*
* @param str
* 要检查的字符串
* @return str为时间型返回true，否则返回false
*/
public static boolean isTimestamp(String str) {
if (isBlank(str))
return false;
try {
java.sql.Date.valueOf(str.trim());
return true;
} catch (Exception ex) {
}
return false;
}
/**
* 检查字符串str是否为(yyyy-MM-dd HH:mm:ss)模式的时间
*
* @param str
* 要检查的字符串
* @return str为时间型返回true，否则返回false
*/
public static boolean isFullTimestamp(String str) {
if (isBlank(str))
return false;
try {
SimpleDateFormat format = new SimpleDateFormat(
"yyyy-MM-dd HH:mm:ss");
Date date = format.parse(str.trim());
return date != null;
} catch (Exception e) {
}
return false;
}
/**
* 将字符数组转换为长整型数组
*
* @param str
* 字符数组
* @return Long[] 长整型数组
*/
public static Long[] stringsToLongs(String str[]) {
Long lon[] = new Long[str.length];
for (int i = 0; i < lon.length; i++)
lon[i] = new Long(str[i]);
return lon;
}
/**
* 将字符数组转换为整型数组
*
* @param str
* 字符数组
* @return Integer[] 整型数组
*/
public static Integer[] stringsToIntegers(String str[]) {
Integer array[] = new Integer[str.length];
for (int i = 0; i < array.length; i++)
array[i] = new Integer(str[i]);
return array;
}
/**
* 将字符数组转换为布尔型数组
*
* @param str
* 字符数组
* @return Boolean[] 布尔型数组
*/
public static Boolean[] stringsToBooleans(String str[]) {
Boolean array[] = new Boolean[str.length];
for (int i = 0; i < array.length; i++)
array[i] = new Boolean(str[i]);
return array;
}
/**
* 将字符数组转换为浮点型数组
*
* @param str
* 字符数组
* @return double[] 浮点型数组
*/
public static double[] stringsToDoubles(String str[]) {
double array[] = new double[str.length];
for (int i = 0; i < array.length; i++)
array[i] = Double.parseDouble(str[i]);
return array;
}
/**
* 得到数字格式化后的字符串
*
* @param number
* Number类型
* @param minFractionDigits
* 小数最小位数
* @param maxFractionDigits
* 小数最大位数
* @return String 格式化后的字符串
*/
public static String formatNumber(Number number, int minFractionDigits,
int maxFractionDigits) {
NumberFormat format = NumberFormat.getInstance();
format.setMinimumFractionDigits(minFractionDigits);
format.setMaximumFractionDigits(maxFractionDigits);
return format.format(number);
}
/**
* 字符串高亮<br>
* 解决了高亮前缀或高亮后缀在要高亮显示的字符串数组在存在时的问题，根据本算法可解决JS高亮显示时相同的问题
*
* @param text
* 内容
* @param replaceStrs
* 要高亮显示的字符串数组
* @param beginStr
* 高亮前缀，如<font color=red>
* @param endStr
* 高亮后缀，如</font>
* @return
*/
public static String heightLight(String text, String[] replaceStrs,
String beginStr, String endStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(heightLight(beforeStr, replaceStrs, beginStr,
endStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(beginStr).append(replaceStr).append(endStr);
str.append(heightLight(afterStr, replaceStrs, beginStr, endStr));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串数组为一个字符串<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStrs
* @param newStr
* @return
*/
public static String replaceAll(String text, String[] replaceStrs,
String newStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAll(beforeStr, replaceStrs, newStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStr);
str.append(replaceAll(afterStr, replaceStrs, newStr));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串为一个字符串<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStr
* @param newStr
* @return
*/
public static String replaceAll(String text, String replaceStr,
String newStr) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAll(beforeStr, replaceStr, newStr));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStr);
str.append(replaceAll(afterStr, replaceStr, newStr));
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 替换指定的字符串数组为一个字符串数组<br>
* 速度比String.replaceAll快3倍左右，比apache-common StringUtils.replace快2倍左右
*
* @param text
* @param replaceStrs
* @param newStrs
* @return
*/
public static String replaceAllArray(String text, String[] replaceStrs,
String[] newStrs) {
if (text.length() == 0)
return text;
StringBuilder str = new StringBuilder();
for (int i = 0; i < replaceStrs.length; i++) {
String replaceStr = replaceStrs[i];
int index = text.indexOf(replaceStr);
if (index >= 0) {
String afterStr = null;
if (index > 0) {
String beforeStr = text.substring(0, index);
afterStr = text.substring(index + replaceStr.length());
str.append(replaceAllArray(beforeStr, replaceStrs, newStrs));
} else
afterStr = text.substring(replaceStr.length());
str.append(newStrs[i]);
str.append(replaceAllArray(afterStr, replaceStrs, newStrs));
break;
}
}
if (str.length() == 0)
return text;
return str.toString();
}
/**
* 解码HTML(将>,<,",&转换成>,<,",& )
*
* @param html
* @return
*/
public static String decodeHTML(String html) {
if (isBlank(html))
return EMPTY;
String[] replaceStr = { "&", "<", ">", """ };
String[] newStr = { "&", "<", ">", "\"" };
return replaceAllArray(html, replaceStr, newStr);
}
/**
* 编码HTML(将>,<,",&
* 转换成>,<,",&)(高效率，来自FreeMarker模板源码，比replaceAll速度快很多)
*
* @param html
* @return
*/
public static String encodeHTML(String html) {
if (isBlank(html))
return EMPTY;
int ln = html.length();
char c;
StringBuffer b;
for (int i = 0; i < ln; i++) {
c = html.charAt(i);
if (c == '<' || c == '>' || c == '&' || c == '"') {
b = new StringBuffer(html.substring(0, i));
switch (c) {
case '<':
b.append("<");
break;
case '>':
b.append(">");
break;
case '&':
b.append("&");
break;
case '"':
b.append(""");
break;
}
i++;
int next = i;
while (i < ln) {
c = html.charAt(i);
if (c == '<' || c == '>' || c == '&' || c == '"') {
b.append(html.substring(next, i));
switch (c) {
case '<':
b.append("<");
break;
case '>':
b.append(">");
break;
case '&':
b.append("&");
break;
case '"':
b.append(""");
break;
}
next = i + 1;
}
i++;
}
if (next < ln)
b.append(html.substring(next));
html = b.toString();
break;
}
}
return html;
}
/**
* MD5加密
*
* @param plainText
* 要加密的字符串
* @return 加密后的字符串
*/
public static String Md5(String plainText) {
StringBuffer buf = new StringBuffer(EMPTY);
try {
MessageDigest md = MessageDigest.getInstance("MD5");
md.update(plainText.getBytes());
byte b[] = md.digest();
int i = 0;
for (int offset = 0; offset < b.length; offset++) {
i = b[offset];
if (i < 0)
i += 256;
if (i < 16)
buf.append("0");
buf.append(Integer.toHexString(i));
}
} catch (Exception e) {
e.printStackTrace();
}
return buf.toString();
}
/**
* MD5加密(32)
*
* @param plainText
* 要加密的字符串
* @return
*/
public final static String MD5(String plainText) {
char hexDigits[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'a', 'b', 'c', 'd', 'e', 'f' };
try {
byte[] strTemp = plainText.getBytes();
MessageDigest mdTemp = MessageDigest.getInstance("MD5");
mdTemp.update(strTemp);
byte[] md = mdTemp.digest();
int j = md.length;
char str[] = new char[j * 2];
int k = 0;
for (int i = 0; i < j; i++) {
byte byte0 = md[i];
str[k++] = hexDigits[byte0 >>> 4 & 0xf];
str[k++] = hexDigits[byte0 & 0xf];
}
return new String(str);
} catch (Exception e) {
}
return "";
}
// Empty checks
// -----------------------------------------------------------------------
/**
* <p>
* Checks if a CharSequence is empty ("") or null.
* </p>
*
* <pre>
* StringUtils.isEmpty(null) = true
* StringUtils.isEmpty("") = true
* StringUtils.isEmpty(" ") = false
* StringUtils.isEmpty("bob") = false
* StringUtils.isEmpty(" bob ") = false
* </pre>
*
* <p>
* NOTE: This method changed in Lang version 2.0. It no longer trims the
* CharSequence. That functionality is available in isBlank().
* </p>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is empty or null
*/
public static boolean isEmpty(CharSequence cs) {
return cs == null || cs.length() == 0;
}
/**
* <p>
* Checks if a CharSequence is not empty ("") and not null.
* </p>
*
* <pre>
* StringUtils.isNotEmpty(null) = false
* StringUtils.isNotEmpty("") = false
* StringUtils.isNotEmpty(" ") = true
* StringUtils.isNotEmpty("bob") = true
* StringUtils.isNotEmpty(" bob ") = true
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if the CharSequence is not empty and not null
* @since 3.0 Changed signature from isNotEmpty(String) to
* isNotEmpty(CharSequence)
*/
public static boolean isNotEmpty(CharSequence cs) {
return !isEmpty(cs);
}
// Trim
// -----------------------------------------------------------------------
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String,
* handling {@code null} by returning {@code null}.
* </p>
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use {@link #strip(String)}.
* </p>
*
* <p>
* To trim your choice of characters, use the {@link #strip(String, String)}
* methods.
* </p>
*
* <pre>
* StringUtils.trim(null) = null
* StringUtils.trim("") = ""
* StringUtils.trim(" ") = ""
* StringUtils.trim("abc") = "abc"
* StringUtils.trim(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed string, {@code null} if null String input
*/
public static String trim(String str) {
return str == null ? null : str.trim();
}
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String
* returning {@code null} if the String is empty ("") after the trim or if
* it is {@code null}.
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use
* {@link #stripToNull(String)}.
* </p>
*
* <pre>
* StringUtils.trimToNull(null) = null
* StringUtils.trimToNull("") = null
* StringUtils.trimToNull(" ") = null
* StringUtils.trimToNull("abc") = "abc"
* StringUtils.trimToNull(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed String, {@code null} if only chars <= 32, empty or
* null String input
*/
public static String trimToNull(String str) {
String ts = trim(str);
return isEmpty(ts) ? null : ts;
}
/**
* <p>
* Removes control characters (char <= 32) from both ends of this String
* returning an empty String ("") if the String is empty ("") after the trim
* or if it is {@code null}.
*
* <p>
* The String is trimmed using {@link String#trim()}. Trim removes start and
* end characters <= 32. To strip whitespace use
* {@link #stripToEmpty(String)}.
* </p>
*
* <pre>
* StringUtils.trimToEmpty(null) = ""
* StringUtils.trimToEmpty("") = ""
* StringUtils.trimToEmpty(" ") = ""
* StringUtils.trimToEmpty("abc") = "abc"
* StringUtils.trimToEmpty(" abc ") = "abc"
* </pre>
*
* @param str
* the String to be trimmed, may be null
* @return the trimmed String, or an empty String if {@code null} input
*/
public static String trimToEmpty(String str) {
return str == null ? EMPTY : str.trim();
}
// Equals
// -----------------------------------------------------------------------
/**
* <p>
* Compares two CharSequences, returning {@code true} if they are equal.
* </p>
*
* <p>
* {@code null}s are handled without exceptions. Two {@code null} references
* are considered to be equal. The comparison is case sensitive.
* </p>
*
* <pre>
* StringUtils.equals(null, null) = true
* StringUtils.equals(null, "abc") = false
* StringUtils.equals("abc", null) = false
* StringUtils.equals("abc", "abc") = true
* StringUtils.equals("abc", "ABC") = false
* </pre>
*
* @see java.lang.String#equals(Object)
* @param cs1
* the first CharSequence, may be null
* @param cs2
* the second CharSequence, may be null
* @return {@code true} if the CharSequences are equal, case sensitive, or
* both {@code null}
*/
public static boolean equals(CharSequence cs1, CharSequence cs2) {
return cs1 == null ? cs2 == null : cs1.equals(cs2);
}
/**
* <p>
* Compares two CharSequences, returning {@code true} if they are equal
* ignoring the case.
* </p>
*
* <p>
* {@code null}s are handled without exceptions. Two {@code null} references
* are considered equal. Comparison is case insensitive.
* </p>
*
* <pre>
* StringUtils.equalsIgnoreCase(null, null) = true
* StringUtils.equalsIgnoreCase(null, "abc") = false
* StringUtils.equalsIgnoreCase("abc", null) = false
* StringUtils.equalsIgnoreCase("abc", "abc") = true
* StringUtils.equalsIgnoreCase("abc", "ABC") = true
* </pre>
*
* @param str1
* the first CharSequence, may be null
* @param str2
* the second CharSequence, may be null
* @return {@code true} if the CharSequence are equal, case insensitive, or
* both {@code null}
*/
public static boolean equalsIgnoreCase(CharSequence str1, CharSequence str2) {
if (str1 == null || str2 == null) {
return str1 == str2;
} else {
return CharSequenceUtils.regionMatches(str1, true, 0, str2, 0,
Math.max(str1.length(), str2.length()));
}
}
// Case conversion
// -----------------------------------------------------------------------
/**
* <p>
* Converts a String to upper case as per {@link String#toUpperCase()}.
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.upperCase(null) = null
* StringUtils.upperCase("") = ""
* StringUtils.upperCase("aBc") = "ABC"
* </pre>
*
* <p>
* <strong>Note:</strong> As described in the documentation for
* {@link String#toUpperCase()}, the result of this method is affected by
* the current locale. For platform-independent case transformations, the
* method {@link #lowerCase(String, Locale)} should be used with a specific
* locale (e.g. {@link Locale#ENGLISH}).
* </p>
*
* @param str
* the String to upper case, may be null
* @return the upper cased String, {@code null} if null String input
*/
public static String upperCase(String str) {
if (str == null) {
return null;
}
return str.toUpperCase();
}
/**
* <p>
* Converts a String to upper case as per {@link String#toUpperCase(Locale)}
* .
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.upperCase(null, Locale.ENGLISH) = null
* StringUtils.upperCase("", Locale.ENGLISH) = ""
* StringUtils.upperCase("aBc", Locale.ENGLISH) = "ABC"
* </pre>
*
* @param str
* the String to upper case, may be null
* @param locale
* the locale that defines the case transformation rules, must
* not be null
* @return the upper cased String, {@code null} if null String input
*/
public static String upperCase(String str, Locale locale) {
if (str == null) {
return null;
}
return str.toUpperCase(locale);
}
/**
* <p>
* Converts a String to lower case as per {@link String#toLowerCase()}.
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.lowerCase(null) = null
* StringUtils.lowerCase("") = ""
* StringUtils.lowerCase("aBc") = "abc"
* </pre>
*
* <p>
* <strong>Note:</strong> As described in the documentation for
* {@link String#toLowerCase()}, the result of this method is affected by
* the current locale. For platform-independent case transformations, the
* method {@link #lowerCase(String, Locale)} should be used with a specific
* locale (e.g. {@link Locale#ENGLISH}).
* </p>
*
* @param str
* the String to lower case, may be null
* @return the lower cased String, {@code null} if null String input
*/
public static String lowerCase(String str) {
if (str == null) {
return null;
}
return str.toLowerCase();
}
/**
* <p>
* Converts a String to lower case as per {@link String#toLowerCase(Locale)}
* .
* </p>
*
* <p>
* A {@code null} input String returns {@code null}.
* </p>
*
* <pre>
* StringUtils.lowerCase(null, Locale.ENGLISH) = null
* StringUtils.lowerCase("", Locale.ENGLISH) = ""
* StringUtils.lowerCase("aBc", Locale.ENGLISH) = "abc"
* </pre>
*
* @param str
* the String to lower case, may be null
* @param locale
* the locale that defines the case transformation rules, must
* not be null
* @return the lower cased String, {@code null} if null String input
*/
public static String lowerCase(String str, Locale locale) {
if (str == null) {
return null;
}
return str.toLowerCase(locale);
}
/**
* <p>
* Checks if the CharSequence contains only lowercase characters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAllLowerCase(null) = false
* StringUtils.isAllLowerCase("") = false
* StringUtils.isAllLowerCase(" ") = false
* StringUtils.isAllLowerCase("abc") = true
* StringUtils.isAllLowerCase("abC") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains lowercase characters, and is
* non-null
*/
public static boolean isAllLowerCase(CharSequence 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>
* Checks if the CharSequence contains only uppercase characters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty String (length()=0) will
* return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAllUpperCase(null) = false
* StringUtils.isAllUpperCase("") = false
* StringUtils.isAllUpperCase(" ") = false
* StringUtils.isAllUpperCase("ABC") = true
* StringUtils.isAllUpperCase("aBC") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains uppercase characters, and is
* non-null
*/
public static boolean isAllUpperCase(CharSequence cs) {
if (cs == null || 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;
}
// Defaults
// -----------------------------------------------------------------------
/**
* <p>
* Returns either the passed in String, or if the String is {@code null}, an
* empty String ("").
* </p>
*
* <pre>
* StringUtils.defaultString(null) = ""
* StringUtils.defaultString("") = ""
* StringUtils.defaultString("bat") = "bat"
* </pre>
*
* @see ObjectUtils#toString(Object)
* @see String#valueOf(Object)
* @param str
* the String to check, may be null
* @return the passed in String, or the empty String if it was {@code null}
*/
public static String defaultString(String str) {
return str == null ? EMPTY : str;
}
/**
* <p>
* Returns either the passed in String, or if the String is {@code null},
* the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultString(null, "NULL") = "NULL"
* StringUtils.defaultString("", "NULL") = ""
* StringUtils.defaultString("bat", "NULL") = "bat"
* </pre>
*
* @see ObjectUtils#toString(Object,String)
* @see String#valueOf(Object)
* @param str
* the String to check, may be null
* @param defaultStr
* the default String to return if the input is {@code null}, may
* be null
* @return the passed in String, or the default if it was {@code null}
*/
public static String defaultString(String str, String defaultStr) {
return str == null ? defaultStr : str;
}
/**
* <p>
* Returns either the passed in CharSequence, or if the CharSequence is
* whitespace, empty ("") or {@code null}, the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultIfBlank(null, "NULL") = "NULL"
* StringUtils.defaultIfBlank("", "NULL") = "NULL"
* StringUtils.defaultIfBlank(" ", "NULL") = "NULL"
* StringUtils.defaultIfBlank("bat", "NULL") = "bat"
* StringUtils.defaultIfBlank("", null) = null
* </pre>
*
* @param <T>
* the specific kind of CharSequence
* @param str
* the CharSequence to check, may be null
* @param defaultStr
* the default CharSequence to return if the input is whitespace,
* empty ("") or {@code null}, may be null
* @return the passed in CharSequence, or the default
* @see StringUtils#defaultString(String, String)
*/
public static <T extends CharSequence> T defaultIfBlank(T str, T defaultStr) {
return isBlank(str) ? defaultStr : str;
}
/**
* <p>
* Returns either the passed in CharSequence, or if the CharSequence is
* empty or {@code null}, the value of {@code defaultStr}.
* </p>
*
* <pre>
* StringUtils.defaultIfEmpty(null, "NULL") = "NULL"
* StringUtils.defaultIfEmpty("", "NULL") = "NULL"
* StringUtils.defaultIfEmpty("bat", "NULL") = "bat"
* StringUtils.defaultIfEmpty("", null) = null
* </pre>
*
* @param <T>
* the specific kind of CharSequence
* @param str
* the CharSequence to check, may be null
* @param defaultStr
* the default CharSequence to return if the input is empty ("")
* or {@code null}, may be null
* @return the passed in CharSequence, or the default
* @see StringUtils#defaultString(String, String)
*/
public static <T extends CharSequence> T defaultIfEmpty(T str, T defaultStr) {
return isEmpty(str) ? defaultStr : str;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAlpha(null) = false
* StringUtils.isAlpha("") = false
* StringUtils.isAlpha(" ") = false
* StringUtils.isAlpha("abc") = true
* StringUtils.isAlpha("ab2c") = false
* StringUtils.isAlpha("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters, and is non-null
*/
public static boolean isAlpha(CharSequence cs) {
if (cs == null || cs.length() == 0) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetter(cs.charAt(i)) == false) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters and space (' ').
* </p>
*
* <p>
* {@code null} will return {@code false} An empty CharSequence (length()=0)
* will return {@code true}.
* </p>
*
* <pre>
* StringUtils.isAlphaSpace(null) = false
* StringUtils.isAlphaSpace("") = true
* StringUtils.isAlphaSpace(" ") = true
* StringUtils.isAlphaSpace("abc") = true
* StringUtils.isAlphaSpace("ab c") = true
* StringUtils.isAlphaSpace("ab2c") = false
* StringUtils.isAlphaSpace("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters and space, and is non-null
*/
public static boolean isAlphaSpace(CharSequence cs) {
if (cs == null) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetter(cs.charAt(i)) == false)
&& (cs.charAt(i) != ' ')) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters or digits.
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code false}.
* </p>
*
* <pre>
* StringUtils.isAlphanumeric(null) = false
* StringUtils.isAlphanumeric("") = false
* StringUtils.isAlphanumeric(" ") = false
* StringUtils.isAlphanumeric("abc") = true
* StringUtils.isAlphanumeric("ab c") = false
* StringUtils.isAlphanumeric("ab2c") = true
* StringUtils.isAlphanumeric("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters or digits, and is non-null
*/
public static boolean isAlphanumeric(CharSequence cs) {
if (cs == null || cs.length() == 0) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if (Character.isLetterOrDigit(cs.charAt(i)) == false) {
return false;
}
}
return true;
}
/**
* <p>
* Checks if the CharSequence contains only Unicode letters, digits or space
* ({@code ' '}).
* </p>
*
* <p>
* {@code null} will return {@code false}. An empty CharSequence
* (length()=0) will return {@code true}.
* </p>
*
* <pre>
* StringUtils.isAlphanumericSpace(null) = false
* StringUtils.isAlphanumericSpace("") = true
* StringUtils.isAlphanumericSpace(" ") = true
* StringUtils.isAlphanumericSpace("abc") = true
* StringUtils.isAlphanumericSpace("ab c") = true
* StringUtils.isAlphanumericSpace("ab2c") = true
* StringUtils.isAlphanumericSpace("ab-c") = false
* </pre>
*
* @param cs
* the CharSequence to check, may be null
* @return {@code true} if only contains letters, digits or space, and is
* non-null
*/
public static boolean isAlphanumericSpace(CharSequence cs) {
if (cs == null) {
return false;
}
int sz = cs.length();
for (int i = 0; i < sz; i++) {
if ((Character.isLetterOrDigit(cs.charAt(i)) == false)
&& (cs.charAt(i) != ' ')) {
return false;
}
}
return true;
}
public static boolean isDigit(char ch){
if (ch >= '0' && ch <= '9')
return true;
return false;
}
public static boolean isDigit(int ch){
if (ch >= 0 && ch <= 9)
return true;
return false;
}
}
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