isEmpty 和 isBlank 的用法區(qū)別,居然一半的人答不上來.....
isEmpty系列
StringUtils.isEmpty()
StringUtils.isEmpty(null) = trueStringUtils.isEmpty("") = trueStringUtils.isEmpty(" ") = falseStringUtils.isEmpty(“bob”) = falseStringUtils.isEmpty(" bob ") = false/**NOTE: This method changed in Lang version 2.0.
* It no longer trims the CharSequence.* That functionality is available in isBlank().** cs the CharSequence to check, may be null* { true} if the CharSequence is empty or null* 3.0 Changed signature from isEmpty(String) to isEmpty(CharSequence)*/public static boolean isEmpty(final CharSequence cs) {return cs == null || cs.length() == 0;}
StringUtils.isNotEmpty()
public static boolean isNotEmpty(final CharSequence cs) {return !isEmpty(cs);}
StringUtils.isAnyEmpty()
StringUtils.isAnyEmpty(null) = trueStringUtils.isAnyEmpty(null, “foo”) = trueStringUtils.isAnyEmpty("", “bar”) = trueStringUtils.isAnyEmpty(“bob”, “”) = trueStringUtils.isAnyEmpty(" bob ", null) = trueStringUtils.isAnyEmpty(" ", “bar”) = falseStringUtils.isAnyEmpty(“foo”, “bar”) = false/* css the CharSequences to check, may be null or empty* { true} if any of the CharSequences are empty or null* 3.2*/public static boolean isAnyEmpty(final CharSequence... css) {if (ArrayUtils.isEmpty(css)) {return true;}for (final CharSequence cs : css){if (isEmpty(cs)) {return true;}}return false;}
StringUtils.isNoneEmpty()
/*Checks if none of the CharSequences are empty ("") or null.
*** StringUtils.isNoneEmpty(null) = false* StringUtils.isNoneEmpty(null, "foo") = false* StringUtils.isNoneEmpty("", "bar") = false* StringUtils.isNoneEmpty("bob", "") = false* StringUtils.isNoneEmpty(" bob ", null) = false* StringUtils.isNoneEmpty(" ", "bar") = true* StringUtils.isNoneEmpty("foo", "bar") = true*
* * @param css the CharSequences to check, may be null or empty * @return {@code true} if none of the CharSequences are empty or null * @since 3.2 */public?static?boolean?isNoneEmpty(final?CharSequence...?css)?{isBank系列
StringUtils.isBlank()
StringUtils.isBlank(null) = trueStringUtils.isBlank("") = trueStringUtils.isBlank(" ") = trueStringUtils.isBlank(“bob”) = falseStringUtils.isBlank(" bob ") = false/*Checks if a CharSequence is whitespace, empty ("") or null.
* cs the CharSequence to check, may be null* { true} if the CharSequence is null, empty or whitespace* 2.0* 3.0 Changed signature from isBlank(String) to isBlank(CharSequence)*/public static boolean isBlank(final 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;}
StringUtils.isNotBlank()
public static boolean isNotBlank(final CharSequence cs) {return !isBlank(cs);}
StringUtils.isAnyBlank()
StringUtils.isAnyBlank(null) = trueStringUtils.isAnyBlank(null, “foo”) = trueStringUtils.isAnyBlank(null, null) = trueStringUtils.isAnyBlank("", “bar”) = trueStringUtils.isAnyBlank(“bob”, “”) = trueStringUtils.isAnyBlank(" bob ", null) = trueStringUtils.isAnyBlank(" ", “bar”) = trueStringUtils.isAnyBlank(“foo”, “bar”) = false/*Checks if any one of the CharSequences are blank ("") or null and not whitespace only..
* @param css the CharSequences to check, may be null or empty* @return {@code true} if any of the CharSequences are blank or null or whitespace only* @since 3.2*/public static boolean isAnyBlank(final CharSequence... css) {if (ArrayUtils.isEmpty(css)) {return true;}for (final CharSequence cs : css){if (isBlank(cs)) {return true;}}return false;}
StringUtils.isNoneBlank()
StringUtils.isNoneBlank(null) = falseStringUtils.isNoneBlank(null, “foo”) = falseStringUtils.isNoneBlank(null, null) = falseStringUtils.isNoneBlank("", “bar”) = falseStringUtils.isNoneBlank(“bob”, “”) = falseStringUtils.isNoneBlank(" bob ", null) = falseStringUtils.isNoneBlank(" ", “bar”) = falseStringUtils.isNoneBlank(“foo”, “bar”) = true/*Checks if none of the CharSequences are blank ("") or null and whitespace only..
* @param css the CharSequences to check, may be null or empty* @return {@code true} if none of the CharSequences are blank or null or whitespace only* @since 3.2*/public static boolean isNoneBlank(final CharSequence... css) {return !isAnyBlank(css);}
StringUtils的其他方法
https://commons.apache.org/proper/commons-lang/apidocs/org/apache/commons/lang3/StringUtils.html

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