blocks|key|848302|text|假设s不为空：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|848303|Character.isUpperCase(s.charAt(0))|code-block|syntax|javascript|848304|或者，正如divec所提到的，使其适用于码位高于U%2BFFFF的字符。|848305|Character.isUpperCase(s.codePointAt(0));|848306|entityMap^0|2|1|0|0|O|6|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|X|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|Y|8|@]|D|@]|E|$]]]|P|$]]

Assuming <code>s</code> is non-empty:

<pre><code>Character.isUpperCase(s.charAt(0))
</code></pre>

or, as mentioned by divec, to make it work for characters with code points above <code>U+FFFF</code>:

<pre><code>Character.isUpperCase(s.codePointAt(0));
</code></pre>

blocks|key|848328|text|有很多方法可以做到这一点，但最简单的方法似乎是以下一种：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|848329|boolean+isUpperCase+=+Character.isUpperCase("My+String".charAt(0));|code-block|syntax|javascript|848330|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

There is many ways to do that, but the simplest seems to be the following one:

<pre><code>boolean isUpperCase = Character.isUpperCase("My String".charAt(0));
</code></pre>

blocks|key|1062704|text|如果您必须手动检查它，您可以执行int+a+=+s.charAt(0)|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1062705|如果a的值介于65到90之间，则为大写。|1062706|entityMap^0|G|J|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|M|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|N|8|@]|D|@]|E|$]]]|I|$]]

If you have to check it out manually you can do <code>int a = s.charAt(0)</code> 

If the value of a is between 65 to 90 it is upper case.

blocks|key|1062710|text|String+yourString+=+"yadayada";
if+(Character.isUpperCase(yourString.charAt(0)))+{
++++//+print+something
}+else+{
++++//+print+something+else
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1062711|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>String yourString = "yadayada";
if (Character.isUpperCase(yourString.charAt(0))) {
 // print something
} else {
 // print something else
}
</code></pre>

blocks|key|848432|text|我们也可以使用正则表达式来查找大写字母|type|unstyled|depth|inlineStyleRanges|entityRanges|data|848433|private+static+void+findUppercaseFirstLetterInString(String+content)+{
++++Matcher+m+=+Pattern
++++++++++++.compile("([a-z])([a-z]*)",+Pattern.CASE_INSENSITIVE).matcher(
++++++++++++++++++++content);
++++System.out.println("Given+input+string+:+"+%2B+content);
++++while+(m.find())+{
++++++++if+(m.group(1).equals(m.group(1).toUpperCase()))+{
++++++++++++System.out.println("First+Letter+Upper+case+match+found+:"
++++++++++++++++++++%2B+m.group());
++++++++}
++++}
}|code-block|syntax|javascript|848434|查看详细的示例。请访问http://www.onlinecodegeek.com/2015/09/how-to-determines-if-string-starts-with.html|offset|length|848435|entityMap|0|LINK|mutability|MUTABLE|url|http://www.onlinecodegeek.com/2015/09/how-to-determines-if-string-starts-with.html^0|0|0|B|2A|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@]|9|@$I|V|J|W|1|X]]|A|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|R]]]]

we can find upper case letter by using regular expression as well

<pre><code>private static void findUppercaseFirstLetterInString(String content) {
 Matcher m = Pattern
 .compile("([a-z])([a-z]*)", Pattern.CASE_INSENSITIVE).matcher(
 content);
 System.out.println("Given input string : " + content);
 while (m.find()) {
 if (m.group(1).equals(m.group(1).toUpperCase())) {
 System.out.println("First Letter Upper case match found :"
 + m.group());
 }
 }
}
</code></pre>

for detailed example . please visit <a href="http://www.onlinecodegeek.com/2015/09/how-to-determines-if-string-starts-with.html" rel="nofollow">http://www.onlinecodegeek.com/2015/09/how-to-determines-if-string-starts-with.html</a>

blocks|key|1062793|text|不要忘记检查字符串是否为空或null。如果我们忘记检查null或empty，那么如果给定的字符串为null或empty，我们将得到NullPointerException或StringIndexOutOfBoundException。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1062794|public+class+StartWithUpperCase{

++++++++public+static+void+main(String[]+args){

++++++++++++String+str1+=+"";+//StringIndexOfBoundException+if+
++++++++++++++++++++++++++++++//empty+checking+not+handled
++++++++++++String+str2+=+null;+//NullPointerException+if+
++++++++++++++++++++++++++++++++//null+checking+is+not+handled.
++++++++++++String+str3+=+"Starts+with+upper+case";
++++++++++++String+str4+=+"starts+with+lower+case";

++++++++++++System.out.println(startWithUpperCase(str1));+//false
++++++++++++System.out.println(startWithUpperCase(str2));+//false
++++++++++++System.out.println(startWithUpperCase(str3));+//true
++++++++++++System.out.println(startWithUpperCase(str4));+//false



++++++++}

++++++++public+static+boolean+startWithUpperCase(String+givenString){

++++++++++++if(null+==+givenString+%7C%7C+givenString.isEmpty()+)+return+false;
++++++++++++else+return+(Character.isUpperCase(+givenString.codePointAt(0)+)+);
++++++++}

++++}|code-block|syntax|javascript|1062795|entityMap^0|E|4|R|4|1T|K|2E|U|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|L|$]]

Don't forget to check whether the string is empty or <code>null</code>. If we forget checking <code>null</code> or empty then we would get <code>NullPointerException</code> or <code>StringIndexOutOfBoundException</code> if a given String is null or empty. 

<pre><code>public class StartWithUpperCase{

 public static void main(String[] args){

 String str1 = ""; //StringIndexOfBoundException if 
 //empty checking not handled
 String str2 = null; //NullPointerException if 
 //null checking is not handled.
 String str3 = "Starts with upper case";
 String str4 = "starts with lower case";

 System.out.println(startWithUpperCase(str1)); //false
 System.out.println(startWithUpperCase(str2)); //false
 System.out.println(startWithUpperCase(str3)); //true
 System.out.println(startWithUpperCase(str4)); //false



 }

 public static boolean startWithUpperCase(String givenString){

 if(null == givenString || givenString.isEmpty() ) return false;
 else return (Character.isUpperCase( givenString.codePointAt(0) ) );
 }

 }
</code></pre>

blocks|key|1062868|text|确保您首先检查null和null，ten将现有字符串转换为upper。如果想要查看输出，则使用S.O.P，否则使用布尔值，就像Rabiz一样。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1062869|+public+static+void+main(String[]+args)
+{
+++++System.out.println("Enter+name");
+++++Scanner+kb+=+new+Scanner+(System.in);
+++++String+text+=++kb.next();

+++++if+(+null+==+text+%7C%7C+text.isEmpty())
+++++{
+++++++++System.out.println("Text+empty");
+++++}
+++++else+if+(text.charAt(0)+==+(text.toUpperCase().charAt(0)))
+++++{
+++++++++System.out.println("First+letter+in+word+"%2B+text+%2B+"+is+upper+case");
+++++}
++}|code-block|syntax|javascript|1062870|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Make sure you first check for null and empty and ten converts existing string to upper. Use S.O.P if want to see outputs otherwise boolean like Rabiz did.

<pre><code> public static void main(String[] args)
 {
 System.out.println("Enter name");
 Scanner kb = new Scanner (System.in);
 String text = kb.next();

 if ( null == text || text.isEmpty())
 {
 System.out.println("Text empty");
 }
 else if (text.charAt(0) == (text.toUpperCase().charAt(0)))
 {
 System.out.println("First letter in word "+ text + " is upper case");
 }
 }
</code></pre>

In Java, find if the first character in a string is upper case without using regular expressions.

In Java, how to find if first character in a string is upper case without regex

Java

在Java中，在不使用正则表达式的情况下查找字符串中的第一个字符是否为大写。

问在Java中，如何在不使用正则表达式情况下查找字符串的第一个字符是否为大写
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