De java-tekenreeks naarUpperCase() methode retourneert de tekenreeks in hoofdletters. Met andere woorden, het converteert alle tekens van de string naar hoofdletters.
De methode toUpperCase() werkt hetzelfde als de methode toUpperCase(Locale.getDefault()). Intern wordt de standaardlandinstelling gebruikt.
Interne implementatie
public String toUpperCase(Locale locale) { if (locale == null) { throw new NullPointerException(); } int firstLower; final int len = value.length; /* Now check if there are any characters that need to be changed. */ scan: { for (firstLower = 0 ; firstLower = Character.MIN_HIGH_SURROGATE) && (c <= character.max_high_surrogate)) { c="codePointAt(firstLower);" srccount="Character.charCount(c);" } else int uppercasechar="Character.toUpperCaseEx(c);" if ((uppercasechar="=" character.error) || (c !="upperCaseChar))" break scan; firstlower +="srcCount;" return this; char[] result="new" char[len]; * may grow resultoffset="0;" grow, so i+resultoffset is the write location in just copy first few uppercase characters. system.arraycopy(value, 0, result, firstlower); string lang="locale.getLanguage();" boolean localedependent="(lang" =="tr" 'az' 'lt'); upperchararray; upperchar; srcchar; srccount; for (int i="firstLower;" <len; srcchar="(int)value[i];" ((char)srcchar>= Character.MIN_HIGH_SURROGATE && (char)srcChar = Character.MIN_SUPPLEMENTARY_CODE_POINT)) { if (upperChar == Character.ERROR) { if (localeDependent) { upperCharArray = ConditionalSpecialCasing.toUpperCaseCharArray(this, i, locale); } else { upperCharArray = Character.toUpperCaseCharArray(srcChar); } } else if (srcCount == 2) { resultOffset += Character.toChars(upperChar, result, i + resultOffset) - srcCount; continue; } else { upperCharArray = Character.toChars(upperChar); } /* Grow result if needed */ int mapLen = upperCharArray.length; if (mapLen > srcCount) { char[] result2 = new char[result.length + mapLen - srcCount]; System.arraycopy(result, 0, result2, 0, i + resultOffset); result = result2; } for (int x = 0; x <maplen; ++x) { result[i + resultoffset x]="upperCharArray[x];" } - srccount); else resultoffset]="(char)upperChar;" return new string(result, 0, len resultoffset); < pre> <hr> <h3>Signature</h3> <p>There are two variant of toUpperCase() method. The signature or syntax of string toUpperCase() method is given below:</p> <pre> public String toUpperCase() public String toUpperCase(Locale locale) </pre> <p>The second method variant of toUpperCase(), converts all the characters into uppercase using the rules of given Locale.</p> <hr> <h3>Returns</h3> <p>string in uppercase letter.</p> <hr> <h2>Java String toUpperCase() method example</h2> <pre> public class StringUpperExample{ public static void main(String args[]){ String s1='hello string'; String s1upper=s1.toUpperCase(); System.out.println(s1upper); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> HELLO STRING </pre> <h2>Java String toUpperCase(Locale locale) Method Example 2</h2> <pre> import java.util.Locale; public class StringUpperExample2 { public static void main(String[] args) { String s = 'hello string'; String turkish = s.toUpperCase(Locale.forLanguageTag('tr')); String english = s.toUpperCase(Locale.forLanguageTag('en')); System.out.println(turkish);//will print I with dot on upper side System.out.println(english); } }</pre> <p>Output:</p> <pre> HELLO STR?NG HELLO STRING </pre></maplen;></=> De tweede methodevariant van toUpperCase() converteert alle tekens naar hoofdletters met behulp van de regels van een bepaalde landinstelling.
Geeft terug
tekenreeks in hoofdletters.
Voorbeeld van een Java String toUpperCase()-methode
public class StringUpperExample{ public static void main(String args[]){ String s1='hello string'; String s1upper=s1.toUpperCase(); System.out.println(s1upper); }} Test het nu Uitgang:
HELLO STRING
Java String toUpperCase(Locale locale) Methode Voorbeeld 2
import java.util.Locale; public class StringUpperExample2 { public static void main(String[] args) { String s = 'hello string'; String turkish = s.toUpperCase(Locale.forLanguageTag('tr')); String english = s.toUpperCase(Locale.forLanguageTag('en')); System.out.println(turkish);//will print I with dot on upper side System.out.println(english); } } Uitgang:
HELLO STR?NG HELLO STRING