java.lang.string constructors and methods with examples ... · java.lang.stirng constructors and...

java.lang.Stirng Constructors and Methods with Examples

String is a sequence of characters. java.lang.String class provides many constructors and methods to do stringoperations in Java. In this Java Tutorial, we shall see the usage of all the constructors and methods ofjava.lang.String with example programs.

java.lang.String Constructors

String()

String(byte[] bytes)

String(byte[] bytes, Charset charset)

String(byte[] bytes, int offset, int length)

String(byte[] bytes, int offset, int length, Charset charset)

String(byte[] bytes, int offset, int length, String charsetName)

String(byte[] bytes, String charsetName)

String(char[] value)

String(char[] value, int offset, int count)

String(int[] codePoints, int offset, int count)

String(String original)

String(StringBuffer buffer)

String(StringBuilder builder)

java.lang.String Methods

char charAt(int index)

int codePointAt(int index)

int codePointBefore(int index)

int codePointCount(int beginIndex, int endIndex)

int compareTo(String anotherString)

int compareToIgnoreCase(String str)

String concat(String str)

boolean contains(CharSequence s)

java.lang.String Constructors and Methods with Examples

https://www.tutorialkart.com

boolean contentEquals(CharSequence cs)

boolean contentEquals(StringBuffer sb)

static String copyValueOf(char[] data)

static String copyValueOf(char[] data, int offset, int count)

boolean endsW ith(String suffix)

boolean equals(Object anObject)

boolean equalsIgnoreCase(String anotherString)

static String format(Locale l, String format, Object… args)

static String format(String format, Object… args)

byte[] getBytes()

byte[] getBytes(Charset charset)

byte[] getBytes(String charsetName)

void getChars(int srcBegin, int srcEnd, char[] dst, int dstBegin)

int hashCode()

int indexOf(int ch)

int indexOf(int ch, int fromIndex)

int indexOf(String str)

int indexOf(String str, int fromIndex)

String intern()

boolean isEmpty()

static String join(CharSequence delimiter, CharSequence… elements)

static String join(CharSequence delimiter, Iterable<? extends CharSequence> elements)

int lastIndexOf(int ch)

int lastIndexOf(int ch, int fromIndex)

int lastIndexOf(String str)

int lastIndexOf(String str, int fromIndex)

int length()

boolean matches(String regex)

int offsetByCodePoints(int index, int codePointOffset)

boolean regionMatches(boolean ignoreCase, int toffset, String other, int ooffset, int len)

boolean regionMatches(int toffset, String other, int ooffset, int len)

String replace(char oldChar, char newChar)

String replace(CharSequence target, CharSequence replacement)

String replaceAll(String regex, String replacement)

String replaceFirst(String regex, String replacement)

String[] split(String regex)

String[] split(String regex, int limit)

boolean startsW ith(String prefix)

boolean startsW ith(String prefix, int toffset)

CharSequence subSequence(int beginIndex, int endIndex)

String substring(int beginIndex)

String substring(int beginIndex, int endIndex)

char[] toCharArray()

String toLowerCase()

String toLowerCase(Locale locale)

String toString()

String toUpperCase()

String toUpperCase(Locale locale)

String trim()

static String valueOf(boolean b)

static String valueOf(char c)

static String valueOf(char[] data)

static String valueOf(char[] data, int offset, int count)

static String valueOf(double d)

static String valueOf(float f)

static String valueOf(int i)

static String valueOf(long l)

static String valueOf(Object obj)

java.util.String provides following functionalities through its methods :

Work with individual characters of a String

Compare two strings

Pattern Maching

Search a character or sub-string in a String

Uppercase and Lowercase conversions

Sub-String replacements

Representation of primitive data types as Strings

java.lang.String Constructors :

String()

String() constructor creates a new String object which is initialized to an empty character sequence.

Example : An example program to demonstrate String() constructor.

StringClassExample.java to demonstrate String() constructor

public class StringClassExample {

public static void main(String[] args) { String str = new String(); System.out.print("Value of str is \""+str+"\""); }}


public static void main(String[] args) {

String str = new String();

System.out.print("Value of str is \""+str+"\"");

}

}

Output to console is :

Value of str is ""

Value of str is ""

String(byte[] bytes)

Java has a computing platform to run and develop java applications. There are many character sets available tochoose from based on the application you are interested in. The constructor String(byte[] bytes) creates a newstring and initializes it to a sequence of characters based on the interpretation of bytes with the defaultcharacter set of Java.

Example : An example program to demonstrate String(byte[] bytes) constructor.

StringClassExample.java

import java.nio.charset.Charset;

public class




byte[] bytes = {97,98,99,101,102,105,108,110};

String str = new String(bytes);

System.out.println("Value of str is \""+str+"\"");

System.out.println("Default char set is "+Charset.defaultCharset());

}

}


Value of str is "abcefiln"Default char set is UTF-8

Value of str is "abcefiln"

Default char set is UTF-8

String(byte[] bytes, Charset charset)

The constructor String(byte[] bytes, Charset charset) creates a new string and initializes the string with thebytes decoded using the charset speicified.

Example : An example program to demonstrate String(byte[] bytes, Charset charset) constructor.




public static void main(String[] args) { byte[] bytes = {97,98,99,101,102,105,108,110}; String str = new String(bytes, Charset.forName("ISO-8859-1")); System.out.println("Value of str is \""+str+"\" using ISO-8859-1 charset"); String str1 = new String(bytes, Charset.forName("UTF-8")); System.out.println("Val




byte[] bytes = {97,98,99,101,102,105,108,110};

String str = new String(bytes, Charset.forName("ISO-8859-1"));

System.out.println("Value of str is \""+str+"\" using ISO-8859-1 charset");

String str1 = new String(bytes, Charset.forName("UTF-8"));

System.out.println("Value of str1 is \""+str1+"\" using UTF-8 charset");

}

}


Value of str is "abcefiln" using ISO-8859-1 charsetValue of str1 is "abcefiln" using UTF-8 charset

Value of str is "abcefiln" using ISO-8859-1 charset

Value of str1 is "abcefiln" using UTF-8 charset

String(byte[] bytes, int offset, int length)

The constructor String(byte[] bytes, int offset, int length) creates a new string and initialize the string withsequence of characters starting from a position in bytes array specified by “offset”, and considering the“length” number of bytes from the offset.

Example : An example program to demonstrate String(byte[] bytes, int offset, int length) constructor.



public static void main(String[] args) { byte[] bytes = {97,98,99,101,102,105,108,110,111,112,113,114}; //"abcefilnopqr" String str = new String(bytes, 3, 5); System.out.println("Value of str is \""+str+"\""); }}



byte[] bytes = {97,98,99,101,102,105,108,110,111,112,113,114}; //"abcefilnopqr"

String str = new String(bytes, 3, 5);


}

}


Value of str is "efiln"


The bytes when decoded using UTF-8 Charset which is default to the Java Virtual Machine,

bytes = abcefilnopqr

and the offset is given by the integers in bold : 0-a-1-b-2-c-3-e-4-f-5-i-6-l-7-n-8-o-9-p-10-q-11-r-12

Offset = 3 and Lenght = 5 : 3-e-4-f-5-i-6-l-7-n-8 : five bytes starting from offset three is “efiln”

String(byte[] bytes, int offset, int length, Charset charset)

The constructor String(byte[] bytes, int offset, int length, Charset charset) creates a new string and initialize thestring with sequence of characters starting from a position in bytes array specified by “offset”, and consideringthe “length” number of bytes from the offset. The bytes are decoded using the specified charset.

Example : An example program to demonstrate String(byte[] bytes, int offset, int length, Charset charset)constructor.




public static void main(String[] args) { byte[] bytes = {97,98,99,101,102,105,108,110,111,112,113,114}; //"abcefilnopqr" String str = new String(bytes, 3, 5, Charset.forName("ISO-8859-1")); System.out.println("Value of str is \""+str+"\""); }}





String str = new String(bytes, 3, 5, Charset.forName("ISO-8859-1"));


}

}




The bytes when decoded using ISO-8859-1 Charset which is specified in the constructor,




String(byte[] bytes, int offset, int length, String charsetName)

The constructor String(byte[] bytes, int offset, int length, String charsetName) creates a new string andinitializes the string with sequence of characters starting from a position in bytes array specified by “offset”,and considering the “length” number of bytes from the offset. The bytes are decoded using the specifiedcharsetName.

Example : An example program to demonstrate String(byte[] bytes, int offset, int length, String charsetName)constructor.


import java.io.UnsupportedEncodingException;


public static void main(String[] args) { byte[] bytes = {97,98,99,101,102,105,108,110,111,112,113,114}; //"abcefilnopqr" try { String str = new String(bytes, 3, 5, "ISO-8859-1"); System.out.println("Value of str is \""+str+"\""); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } }}





try {

String str = new String(bytes, 3, 5, "ISO-8859-1");


} catch (UnsupportedEncodingException e) {

e.printStackTrace();

}

}

}




The bytes when decoded using ISO-8859-1 Charset which is specified in the constructor,




String(byte[] bytes, String charsetName)

The constructor String(byte[] bytes, String charsetName) creates a new string and initializes the string with thebytes decoded using the charsetName speicified.

Example : An example program to demonstrate String(byte[] bytes, String charsetName) constructor.




public static void




byte[] bytes = {97,98,99,101,102,105,108,110};

try {

String str = new String(bytes, "ISO-8859-1");

System.out.println("Value of str is \""+str+"\" using ISO-8859-1 charset");



}

}

}




String(char[] chars)

The constructor String(char[] chars) creates a new string and initializes the string with the characters fromchars array.

Example : An example program to demonstrate String(char[] chars) constructor.



public static void main(String[] args) { char[] chars = {'t','u','t','o','r','i','a','l','k','a','r','t'}; String str = new String(chars); System.out.println("Value of str is \""+str+"\""); }}



char[] chars = {'t','u','t','o','r','i','a','l','k','a','r','t'};

String str = new String(chars);


}

}


Value of str is "tutorialkart"


String(char[] chars, int offset, int count)

The constructor String(char[] chars, int offset, int count) creates a new string and initializes the string withsequence of characters starting from a position in chars array specified by “offset”, and considering the“length” number of characters from the offset.

Example : An example program to demonstrate String(char[] chars) constructor.



public static void main(String[] args) { char[] chars = {'t','u','t','o','r','i','a','l','k','a','r','t'}; String str = new String(chars); System.out.println("Value of str is \""+str+"\""); }}



char[] chars = {'t','u','t','o','r','i','a','l','k','a','r','t'};

String str = new String(chars);


}

}




chars = tutorialkart

and the offset is given by the integers in bold : 0-t-1-u-2-t-3-o-4-r-5-i-6-a-7-l-8-k-9-a-10-r-11-t-12

Offset = 3 and Length = 4 : 3-o-4-r-5-i-6-a-7 : four characters of chars array starting from offset three is “oria”

String(int[] codePoints, int offset, int count)

The constructor String(int[] codePoints, int offset, int count) creates a new string and initializes the string withsequence of Unicode code points starting from a position in codePoints integer array specified by “offset”, andconsidering the “length” number of Unicode code points from the offset.

Example : An example program to demonstrate String(int[] codePoints, int offset, int count) constructor.



public static void main(String[] args) { int[] codePoints = {116,117,116,111,114,105,97,108,107,97,114,116}; String str = new String(codePoints, 3, 5); System.out.println("Value of str is \""+str+"\""); }}



int[] codePoints = {116,117,116,111,114,105,97,108,107,97,114,116};

String str = new String(codePoints, 3, 5);


}

}


Value of str is "orial"

Value of str is "orial"

Unicode code points of integer array codePoints = tutorialkart

and the offset is given by the integers in bold : 0-t-1-u-2-t-3-o-4-r-5-i-6-a-7-l-8-k-9-a-10-r-11-t-12

Offset = 3 and Length = 5 : 3-o-4-r-5-i-6-a-7-l-8 : five code points of codePoints integer array starting fromoffset three is “orial”

String(String original)

The constructor String(String original) creates a new string and initializes the string with the value of originalstring received in the arguments.

Example : An example program to demonstrate String(String original) constructor.



public static void main(String[] args) { String original = "tutorialkart"; String str = new String(original); System.out.println("Value of str is \""+str+"\""); }}



String original = "tutorialkart";

String str = new String(original);


}

}




String(StringBuffer buffer)

The constructor String(StringBuffer buffer) creates a new string and initializes the string with the sequence ofcharacters present in buffer.

Example : An example program to demonstrate String(StringBuffer buffer) constructor.



public static void main(String[] args) { StringBuffer buffer = new StringBuffer("tutorialkart"); String str = new String(buffer); System.out.println("Value of str is \""+str+"\""); }}



StringBuffer buffer = new StringBuffer("tutorialkart");

String str = new String(buffer);


}

}




String(StringBuilder buffer)

The constructor String(StringBuilder buffer) creates a new string and initializes the string with the sequence ofcharacters present in buffer.

Example : An example program to demonstrate String(StringBuilder buffer) constructor.



public static void main(String[] args) { StringBuilder builder = new StringBuilder("tutorialkart"); String str = new String(builder); System.out.println("Value of str is \""+str+"\""); }}



StringBuilder builder = new StringBuilder("tutorialkart");

String str = new String(builder);


}

}




java.lang.String Methods :

char charAt(int index)

The method java.lang.String.charAt(int index) returns the character value at the index specified in thearguments.Example : An example program to demonstrate charAt(int index) method.



public static void main(String[] args) { String str = "tutorialkart"; char ch1 = str.charAt(5); System.out.println("Character at index 5 is "+ch1); char ch2 = str.charAt(8);



String str = "tutorialkart";

char ch1 = str.charAt(5);

System.out.println("Character at index 5 is "+ch1);

char ch2 = str.charAt(8);

System.out.println("Character at index 8 is "+ch2);

}

}


Character at index 5 is iCharacter at index 8 is k

Character at index 5 is i

Character at index 8 is k

int codePointAt(int index)

The method java.lang.String.codePointAt(int index) returns the Unicode code point at the index specified in thearguements.Example : An example program to demonstrate codePointAt(int index) method.



public static void main(String[] args) { String str = "tutorialkart"; int codePoint1 = str.codePointAt(5); System.out.println("codePoint at index 5 is "+codePoint1); int codePoint2 = str.codePointAt(8); System.out.println("codePoint at index 8 is "+codePoint2); }}




int codePoint1 = str.codePointAt(5);

System.out.println("codePoint at index 5 is "+codePoint1);



}

}


codePoint at index 5 is 105codePoint at index 8 is 107

codePoint at index 5 is 105


int codePointBefore(int index)

The method java.lang.String.codePointBefore(int index) returns the Unicode code point character just beforethe index specified in the arguements.Example : An example program to demonstrate codePointBefore(intindex) method.



public static void main(String[] args) { String str = "tutorialkart"; int codePoint1 = str.codePointAt(5); System.out.println("codePoint at index 5 is "+codePoint1); int codePoint2 = str.codePointBefore(6); System.out.println("codePoint at index before 6 is "+codePoint2); }}






int codePoint2 = str.codePointBefore(6);

System.out.println("codePoint at index before 6 is "+codePoint2);

}

}


codePoint at index 5 is 105codePoint at index before 6 is 105


codePoint at index before 6 is 105

int codePointCount(int beginIndex, int endIndex)

The method java.lang.String.codePointCount(int beginIndex, int endIndex) returns the number of Unicode codepoints in the specified text range of this String.Example : An example program to demonstratecodePointCount(int beginIndex, int endIndex) method.



public static void main(String[] args) { String str = "tutorialkart";




int count = str.codePointCount(2,5);

System.out.println("number of code points from 2 to 5 is "+count);

}

}


number of code points from 2 to 5 is 3

number of code points from 2 to 5 is 3

int compareTo(String anotherString)

The method java.lang.String.compareTo(String anotherString) compares two strings lexicographically (the orderin which words are arranged in a dictionary). Returns a positive value if the string should occur later to thestring provided in the arguements. Returns a negative value if the string should occur prior to the stringprovided in the arguements.Example : An example program to demonstrate compareTo(String anotherString)method.



public static void main(String[] args) { compare("tutorialkart","tutorialkart"); compare("tutorialkart","autorialkart"); compare("autorialkart","tutorialkart"); } public static void compare(String str, String anotherStr){ int difference = str.compareTo(anotherStr); if(difference < 0){ System.out.println("The string, \""+str+"\" should occur prior to the string, \""+anotherStr+"\" provided in the arguements."); } else if(difference >0){



compare("tutorialkart","tutorialkart");

compare("tutorialkart","autorialkart");

compare("autorialkart","tutorialkart");

}

public static void compare(String str, String anotherStr){

int difference = str.compareTo(anotherStr);

if(difference < 0){ System.out.println("The string, \""+str+"\" should occur prior to the string, \""+anotherStr+"\"

provided in the arguements."); } else if(difference >0){

System.out.println("The string, \""+str+"\" should occur later to the string, \""+anotherStr+"\" provided in the

arguements.");

} else {

System.out.println("The two strings, \""+str+"\" and \""+anotherStr+"\" are equal.");

}

}

}


The two strings, "tutorialkart" and "tutorialkart" are equal.The string, "tutorialkart" should occur later to the string, "autorialkart" provided in the arguements.The string, "autorialkart" should occur prior to the string, "tutorialkart" provided in the arguements.

The two strings, "tutorialkart" and "tutorialkart" are equal.

The string, "tutorialkart" should occur later to the string, "autorialkart" provided in the arguements.

The string, "autorialkart" should occur prior to the string, "tutorialkart" provided in the arguements.

int compareToIgnoreCase(String anotherString)

The method java.lang.String.compareToIgnoreCase(String anotherString) compares two stringslexicographically (the order in which words are arranged in a dictionary) without considering if characters’case. Returns a negative value if the string should occur later to the string provided in the arguements Returnsa negative value if the string should occur prior to the string provided in the arguementsExample : An exampleprogram to demonstrate compareToIgnoreCase(String anotherString) method.



public static void main(String[] args) { compare("Tutorialkart","tutorialkart"); compare("tutorialkart","AutoRialkart");



compare("Tutorialkart","tutorialkart");

compare("tutorialkart","AutoRialkart");

compare("AutorialkaRt","tutoriAlkart");

}

public static void compare(String str, String anotherStr){

int difference = str.compareToIgnoreCase(anotherStr);

if(difference < 0){ System.out.println("The string, \""+str+"\" should occur prior to the string, \""+anotherStr+"\"

provided in the arguements."); } else if(difference >0){

System.out.println("The string, \""+str+"\" should occur later to the string, \""+anotherStr+"\" provided in the

arguements.");

} else {

System.out.println("The two strings, \""+str+"\" and \""+anotherStr+"\" are equal.");

}

}

}


The two strings, "Tutorialkart" and "tutorialkart" are equal.The string, "tutorialkart" should occur later to the string, "AutoRialkart" provided in the arguements.The string, "AutorialkaRt" should occur prior to the string, "tutoriAlkart" provided in the arguements.

The two strings, "Tutorialkart" and "tutorialkart" are equal.

The string, "tutorialkart" should occur later to the string, "AutoRialkart" provided in the arguements.

The string, "AutorialkaRt" should occur prior to the string, "tutoriAlkart" provided in the arguements.

String concat(String str)

The method java.lang.String.concat(String str) concatenates the string specified in the arguements to the endof this string.Example : An example program to demonstrate concat(String str) method.



public static void main(String[] args) { String thisStr = "tutorialkart"; String str = ".com is the best website to understand java programming language."; String resultStr = thisStr.concat(str); System.out.println(resultStr);



String thisStr = "tutorialkart";

String str = ".com is the best website to understand java programming language.";

String resultStr = thisStr.concat(str);

System.out.println(resultStr);

}

}


tutorialkart.com is the best website to understand java programming language.

tutorialkart.com is the best website to understand java programming language.

boolean contains(CharSequence s)

The method java.lang.String.contains(CharSequence s) returns true if and only if this string contains thesequence of char values specified in the arguements.Example : An example program to demonstratecontains(CharSequence s) method.



public static void main(String[] args) { CharSequence chSeq = "kart"; String str = "tutorialkart"; boolean isPresent = str.contains(chSeq); if(isPresent){ System.out.println("CharSequence \""+chSeq+"\" is present in the str, \""+str+"\""); } else { System.out.println("CharSequence \""+chSeq+"\" is not present in the str, \""+str+"\""); } }}



CharSequence chSeq = "kart";


boolean isPresent = str.contains(chSeq);

if(isPresent){

System.out.println("CharSequence \""+chSeq+"\" is present in the str, \""+str+"\"");

} else {

System.out.println("CharSequence \""+chSeq+"\" is not present in the str, \""+str+"\"");

}

}

}


CharSequence "kart" is present in the str, "tutorialkart"

CharSequence "kart" is present in the str, "tutorialkart"

boolean contentEquals(CharSequence cs)

The method java.lang.String.contentEquals(CharSequence cs) compares this string to the specifiedCharSequence and returns true if both the String and CharSequence are equal, else it returns false.Example :An example program to demonstrate contentEquals(CharSequence cs) method.



public static void main(String[] args) { CharSequence chSeq = "tutorialkart"; String str = "tutorialkart"; boolean isPresent = str.contentEquals(chSeq); if(isPresent){ System.out.println("CharSequence \""+chSeq+"\" equals the string str, \""+str+"\""); } else { System.out.println("CharSequence \""+chSeq+"\" is not equal to the string str, \""+str+"\""); } }}



CharSequence chSeq = "tutorialkart";


boolean isPresent = str.contentEquals(chSeq);

if(isPresent){

System.out.println("CharSequence \""+chSeq+"\" equals the string str, \""+str+"\"");

} else {

System.out.println("CharSequence \""+chSeq+"\" is not equal to the string str, \""+str+"\"");

}

}

}


CharSequence "tutorialkart" equals the string str, "tutorialkart"


boolean contentEquals(StringBuffer sb)

The method java.lang.String.contentEquals(StringBuffer sb) compares this string to the specified StringBuffer,and returns true if both the String and StringBuffer are equal, else it returns false.Example : An exampleprogram to demonstrate contentEquals(StringBuffer sb) method.



public static void main(String[] args) { StringBuffer buffer = new StringBuffer("tutorialkart"); String str = "tutorialkart"; boolean isPresent = str.contentEquals(buffer); if(isPresent){ System.out.println("CharSequence \""+buffer+"\" equals the string str, \""+str+"\""); } else { System.out.println("CharSequence \""+buffer+"\" is not equal to the string str, \""+str+"\""); } }}



StringBuffer buffer = new StringBuffer("tutorialkart");


boolean isPresent = str.contentEquals(buffer);

if(isPresent){

System.out.println("CharSequence \""+buffer+"\" equals the string str, \""+str+"\"");

} else {

System.out.println("CharSequence \""+buffer+"\" is not equal to the string str, \""+str+"\"");

}

}

}




static String copyValueOf(char[] data)

This method java.lang.String.copyValueOf(char[] data) creates a new String object with the sequence ofcharacters speicified by char[] data.Example : An example program to demonstrate copyValueOf(char[]data) method.



public static void main(String[] args) { char[] chArr = {'t','u','t','o','r','i','a','l','k','a','r','t'}; String str = String.copyValueOf(chArr); System.out.println("Value of str is \""+str+"\""); }}



char[] chArr = {'t','u','t','o','r','i','a','l','k','a','r','t'};

String str = String.copyValueOf(chArr);


}

}




static String copyValueOf(char[] data, int offset, int count)

This method java.lang.String.copyValueOf(char[] data, int offset, int count) creates a new string object with thesequence of “count” number of characters of char[] data starting from offset position.Example : An exampleprogram to demonstrate copyValueOf(char[] data, int offset, int count) method.



public static void main(String[] args) { char[] chArr = {'t','u','t','o','r','i','a','l','k','a','r','t'}; String str = String.copyValueOf(chArr,6,5); System.out.println("Value of str is \""+str+"\""); }}



char[] chArr = {'t','u','t','o','r','i','a','l','k','a','r','t'};

String str = String.copyValueOf(chArr,6,5);


}

}


Value of str is "alkar"

Value of str is "alkar"

boolean endsWith(String suffix)

The method java.lang.String.endsWith(String suffix) tests if this string ends with the specified suffix.Example :An example program to demonstrate endsWith(String suffix) method.



public static void main(String[] args) { String str = "tutorialkart"; String suffix = "kart"; boolean isEnding = str.endsWith(suffix); if(isEnding){




String suffix = "kart";

boolean isEnding = str.endsWith(suffix);

if(isEnding){

System.out.println("Suffix \""+suffix+"\" is present at the end of string str, \""+str+"\"");

} else {

System.out.println("Suffix \""+suffix+"\" is not present at the end of string str, \""+str+"\"");

}

}

}


Suffix "kart" is present at the end of string str, "tutorialkart"

Suffix "kart" is present at the end of string str, "tutorialkart"

boolean equals(Object anObject)

The method java.lang.String.equals(Object anObject) compares this string to the specified object.Example : Anexample program to demonstrate equals(Object anObject) method.



public static void main(String[] args) { String str = "tutorialkart"; Object otherStr = "kart"; boolean isEqual = str.equals(otherStr); if(isEqual){ System.out.println("Two string, \""+otherStr+"\" and \""+str+"\" are equal."); } else { System.out.println("Two string, \""+otherStr+"\" and \""+str+"\" are not equal."); } }}




Object otherStr = "kart";

boolean isEqual = str.equals(otherStr);

if(isEqual){

System.out.println("Two string, \""+otherStr+"\" and \""+str+"\" are equal.");

} else {

System.out.println("Two string, \""+otherStr+"\" and \""+str+"\" are not equal.");

}

}

}


Two string, "kart" and "tutorialkart" are not equal.

Two string, "kart" and "tutorialkart" are not equal.

boolean equalsIgnoreCase(String anotherString)

The method java.lang.String.equalsIgnoreCase(String anotherString) compares this String to another String,ignoring if the characters in the Strings are uppercase or lowercase.Example : An example program todemonstrate equalsIgnoreCase(String anotherString) method.



public static void main(String[] args) { String str = "tutorialkart"; String otherStr = "TUTORIALKART"; boolean isEqual = str.equalsIgnoreCase(otherStr); if(isEqual){ System.out.println("Two strings, \""+otherStr+"\" and \""+str+"\" are equal."); } else { System.out.println("Two strings, \""+otherStr+"\" and \""+str+"\" are not equal."); } }}




String otherStr = "TUTORIALKART";

boolean isEqual = str.equalsIgnoreCase(otherStr);

if(isEqual){

System.out.println("Two strings, \""+otherStr+"\" and \""+str+"\" are equal.");

} else {

System.out.println("Two strings, \""+otherStr+"\" and \""+str+"\" are not equal.");

}

}

}


Two string, "TUTORIALKART" and "tutorialkart" are equal.

Two string, "TUTORIALKART" and "tutorialkart" are equal.

static String format(Locale l, String format, Object… args)

The method java.lang.String.format(Locale l, String format, Object… args) returns a formatted string using thespecified locale, format string, and arguments.Example : An example program to demonstrate format(Locale l,String format, Object… args) method.


import java.util.Locale;


public static void main(String[] args) { String str = String.format(Locale.ENGLISH,"%s %d days %s", "There are",365,"in an year."); System.out.println(str); }}

import java.util.Locale;



String str = String.format(Locale.ENGLISH,"%s %d days %s", "There are",365,"in an year.");

System.out.println(str);

}

}


There are 365 days in an year.


In the above program : “Locale” is Locale.ENGLISH “format” is : “%s %d days %s” And there are three args(%s,%d,%s in format string) respectively are : “There are”, 365, “in an year.”

static String format(String format, Object… args)

The method java.lang.String.format(String format, Object… args) returns a formatted string using the specifiedformat string and arguments.Example : An example program to demonstrate format(String format, Object…args) method.



public static void main(String[] args) { String str = String.format("%s %d days %s", "There are",365,"in an year."); System.out.println(str); }}



String str = String.format("%s %d days %s", "There are",365,"in an year.");

System.out.println(str);

}

}




In the above program “format” is : “%s %d days %s” And there are three args : “There are”, 365, “in an year.”

byte[] getBytes()

The method java.lang.String.getBytes() encodes this String into a sequence of bytes using the platform’sdefault charset, storing the result into a new byte array.Example : An example program to demonstrategetBytes() method.



public static void main(String[] args) { String str = "tutorialkart"; byte[] bytes = str.getBytes(); System.out.print("The bytes are : "); for(byte b:bytes) System.out.print(b+","); }}




byte[] bytes = str.getBytes();

System.out.print("The bytes are : ");

for(byte b:bytes) System.out.print(b+",");

}

}


The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

byte[] getBytes(Charset charset)

The method java.lang.String.getBytes(Charset charset) encodes this String into a sequence of bytes using thegiven charset, storing the result into a new byte array.Example : An example program to demonstrategetBytes(Charset charset) method.



public class





byte[] bytes = str.getBytes(Charset.forName("UTF-8"));



}

}


The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

byte[] getBytes(String charsetName)

The method java.lang.String.getBytes(String charsetName) encodes this String into a sequence of bytes usingthe named charset, storing the result into a new byte array.Example : An example to demonstrategetBytes(String charsetName) method.




public static void main(String[] args) { String str = "tutorialkart"; byte[] bytes = null; try { bytes = str.getBytes("UTF-8"); } catch (UnsupportedEncodingException e) { // TODO Auto-generated catch block e.printStackTrace(); } System.out.print("The bytes are : "); for(byte b:bytes) System.out.print(b+","); }}





byte[] bytes = null;

try {

bytes = str.getBytes("UTF-8");


// TODO Auto-generated catch block


}



}

}


The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

The bytes are : 116,117,116,111,114,105,97,108,107,97,114,116,

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