publicclassLowerCaseCheck{publicstaticbooleanisAllLowerCase(Stringstr){char[]charArray=str.toCharArray();for(charc:charArray){if(!Character.isLowerCase(c)){returnfalse;}}returntrue;}publicstaticvoidmain(String[]args){Stringstr1="hello";Stringstr2="HelloWorld";System.out.println(isAllLowerCase(str1)...
char是Java中的基本数据类型，用于存储单个字符。Character是Java中的一个类，是char的包装类，用于将基本数据类型封装为对象。内存占用：char作为基本数据类型，直接存储字符值，占用固定的内存空间。Character作为对象，除了存储字符值外，还包含对象头等信息，因此内存占用相对较大。操作方法：char作为基本数据...
String str1 ="The first character '"+ch1 +"' is in lowercase:"+ b1; String str2 ="The second character '"+ch2 +"' is in lowercase:"+ b2; String str3 ="The third character '"+ch3 +"' is in lowercase:"+ b3;// Print the values of b1, b2 and b3.System.out.println( str1...
numberPresent && upperCasePresent && lowerCasePresent && specialCharacterPresent; } We should note a few things here. Basic idea is that we iterate through ourStringand check if its characters are of required types. By usingCharacterclass, we can easily check if a certain character is a digit,...
publicclassLowerCaseCheck{publicstaticbooleanisLowerCase(Stringstr){for(inti=0;i<str.length();i++){charc=str.charAt(i);if(!Character.isLowerCase(c)){returnfalse;}}returntrue;}publicstaticvoidmain(String[]args){Stringstr1="hello";Stringstr2="Hello";System.out.println(isLowerCase(str1));// ...
Another idea is walking through the characters in the input string. We can determine the result once we detect a character that isn’t upper/lowercase. Sowe can skip any further checking. We can useString.toCharArray()to break a string into achararray.Also, theCharacter.isLowerCase()andCharact...
static char toLowerCase(char ch)converts to lowercase. publicclassMain{publicstaticvoidmain(String[] argv){ System.out.println(Character.toTitleCase('a')); System.out.println(Character.toUpperCase('a')); System.out.println(Character.toLowerCase('a'));//fromjava2s.com} } ...
基本数据类型用于存储简单类型的数据,比如说,int、long、byte、short 用于存储整数,float、double 用于存储浮点数,char 用于存储字符,boolean 用于存储布尔值。 不同的基本数据类型,有不同的默认值和大小,来个表格感受下。 引用类型用于存储对象(null 表示没有值的对象)的引用,String 是引用类型的最佳代表,比如说Stri...
The Character class wraps a value of the primitive type char in an object. An object of class Character contains a single field whose type is char. In addition, this class provides a large number of static methods for determining a character's category (lowercase letter, digit, etc.) and...
String s; char [] arr = s.toCharArray();//将String 转array String.valueOf(arr);//将array转String 集合<> string 1、集合转字符串 Set<String> set1 = new HashSet<>(); set1.add("a"); set1.add("b"); System.out.println(StringUtils.join(set1.toArray(), ","));//a,b List<St...