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Found 34494 Articles for Programming
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
2K+ Views
To perform Bubble Sort, try the below given code. In this each each pair of adjacent elements is compared and the elements are swapped if they are not in order.The following is an example.Example Live Demopublic class Demo { public static void main(String []args) { String str[] = { "s", "k", "r", "v", "n"}; String temp; System.out.println("Sorted string..."); for (int j = 0; j < str.length; j++) { for (int i = j + 1; i < str.length; i++) { ... Read More
![karthikeya Boyini](https://www.tutorialspoint.com/assets/profiles/13518/profile/60_31598-1537784993.jpg)
14K+ Views
To locate a substring in a string, use the indexOf() method.Let’s say the following is our string.String str = "testdemo";Find a substring ‘demo’ in a string and get the index.int index = str.indexOf( 'demo');Example Live Demopublic class Demo { public static void main(String []args) { String str = "testdemo"; System.out.println("String: "+str); int index = str.indexOf("demo"); System.out.printf("Substring 'demo' is at index %d", index); } }OutputString: testdemo Substring 'demo' is at index 4
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
13K+ Views
To locate a character in a string, use the indexOf() method.Let’s say the following is our string.String str = "testdemo";Find a character ‘d’ in a string and get the index.int index = str.indexOf( 'd');Example Live Demopublic class Demo { public static void main(String []args) { String str = "testdemo"; System.out.println("String: "+str); int index = str.indexOf( 'd' ); System.out.printf("'d' is at index %d, index); } }OutputString: testdemo 'd' is at index 4Let us see another example. The method returns -1, if the character isn’t found −Example Live Demopublic class ... Read More
![karthikeya Boyini](https://www.tutorialspoint.com/assets/profiles/13518/profile/60_31598-1537784993.jpg)
3K+ Views
Let’s say the following is our string with special characters.String str = "test*$demo";Check for the special characters.Pattern pattern = Pattern.compile("[^A-Za-z0-9]"); Matcher match = pattern.matcher(str); boolean val = match.find();Now, if the bool value “val” is true, that would mean the special characters are in the string.if (val == true) System.out.println("Special characters are in the string.");Example Live Demoimport java.util.regex.Matcher; import java.util.regex.Pattern; public class Demo { public static void main(String []args) { String str = "test*$demo"; System.out.println("String: "+str); Pattern pattern = Pattern.compile("[^A-Za-z0-9]"); Matcher match = pattern.matcher(str); boolean val ... Read More
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
953 Views
The following is our string.String str = "4434";To check whether the above string has only digit characters, try the following if condition that uses matches() method and checks for every character.if(str.matches("[0-9]+") && str.length() > 2) { System.out.println("String contains only digits!"); }Example Live Demopublic class Demo { public static void main(String []args) { String str = "4434"; if(str.matches("[0-9]+") && str.length() > 2) { System.out.println("String contains only digits!"); } } }OutputString contains only digits!Let us see another example.Example Live Demopublic class Demo { public static void main(String []args) ... Read More
![karthikeya Boyini](https://www.tutorialspoint.com/assets/profiles/13518/profile/60_31598-1537784993.jpg)
103 Views
To delete all whitespaces from a string, use the replaceAll() method and replace every whitespace with empty.Let’s say the following is our string.String str = "This is it!";Now, let us replace the whitespaces that will eventually delete them.String res = str.replaceAll("\s+","");Example Live Demopublic class Demo { public static void main(String []args) { String str = "This is it!"; System.out.println("String: "+str); String res = str.replaceAll("\s+",""); System.out.println("String after deleting whitespace: "+res); } }OutputString: This is it! String after deleting whitespace: Thisisit!
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
12K+ Views
To swap the case of a string, use.toLowerCase() for title case string. toLowerCase() for uppercase stringtoUpperCase() for lowercase stringLoop through what we discussed above for all the characters in the sting.for (int i = 0; i > len; i++) { c = str.charAt(i); // title case converted to lower case if (Character.isTitleCase(c)) { c = Character.toLowerCase(c); } // upper case converted to lower case if (Character.isUpperCase(c)) { c = Character.toLowerCase(c); } // lower case converted to upper case if (Character.isLowerCase(c)) { c ... Read More
![karthikeya Boyini](https://www.tutorialspoint.com/assets/profiles/13518/profile/60_31598-1537784993.jpg)
412 Views
To construct on string from another, firstly take a charcter array for the first string.char ch[] = { 'A', 'M', 'I', 'T' }; String str1 = new String(ch);The above forms first string. Now, let us created another string from the first string.String str2 = new String(str1);In this way, we can easily construct one string from another.Example Live Demopublic class Demo { public static void main(String[] args) { char ch[] = { 'A', 'M', 'I', 'T' }; String str1 = new String(ch); String str2 = new String(str1); String str3 ... Read More
![karthikeya Boyini](https://www.tutorialspoint.com/assets/profiles/13518/profile/60_31598-1537784993.jpg)
3K+ Views
To extract a substring as an array of characters in Java, use the getChars() method.Let’s say the following is our string and character array.String str = "World is not enough!"; char[] chArr = new char[10];Now, use the getChars() method to extract a substring.str.getChars(13, 19, chArr, 0);The above substring is an array of characters which can be displayed as shown in the complete example below −Example Live Demopublic class Demo { public static void main(String[] args) { String str = "World is not enough!"; char[] chArr = new char[10]; str.getChars(13, 19, chArr, ... Read More
![Samual Sam](https://www.tutorialspoint.com/assets/profiles/13514/profile/60_83486-1512649303.jpg)
349 Views
To get a string from a subset of the character array elements, use the copyValueOf() method. This method returns a String that represents the character sequence in the array specified.Here is our character array.char[] ch = { 'T', 'E', 'S', 'T', 'I', 'N', 'G'};Now, let us create a string from the subset of the above array elements.String str = String.copyValueOf(ch, 4, 2);Example Live Demopublic class Demo { public static void main(String[] args) { char[] ch = { 'T', 'E', 'S', 'T', 'I', 'N', 'G'}; String str = String.copyValueOf(ch, 4, 2); System.out.println(str); } }OutputIN