/**
* 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);
}
/**
* 检查是否都是大写.
*
* <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;
}