The subexpression/metacharacter “\G” matches the point where the last match finished.Exampleimport java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\G[0-9]";       Scanner sc = new Scanner(System.in);       System.out.println("Enter a string: ");       String input = sc.nextLine();       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       String digits = "";       System.out.println("Digits in the previous match:");       while(m.find()) {   ... Read More

The subexpression/metacharacter “\D” matches the non-digits.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\D";       String input = "This is sample text 12 24 56 89 24";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 24Example 2import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public ... Read More

The subexpression/metacharacter “\d” matches the digits.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\d 24";       String input = "This is sample text 12 24 56 89 24";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 2Example 2Following is a Java program that ... Read More

The subexpression/metacharacter “\S” matches the non-white space characters.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\S";       String input = "Hello how are you welcome to Tutorialspoint !";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 38Example 2import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; ... Read More

The subexpression/metacharacter “\s” matches the white space equivalent.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\s";       String input = "Hello how are you welcome to Tutorialspoint !";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 7Example 2The following example reads a string ... Read More

The subexpression/metacharacter “\W” matches the non-word characters.Example1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main(String args[]) {       String regex = "\W!";       String input = "Hello how are you welcome to Tutorialspoint !";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 1Example2Following example reads 5 string values and prints those that contain ... Read More

The subexpression/metacharacter “\w” matches the word characters i.e. a to z and A to Z and 0 to 9.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "\w to";       String input = "Hello how are you welcome to Tutorialspoint";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);   ... Read More

The subexpression/metacharacter “[^...]” matches any single character, not in brackets.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class SpecifiedCharacters {    public static void main( String args[] ) {       String regex = "[^hwtyoupi]";       String input = "Hi how are you welcome to Tutorialspoint";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 21Example 2The following Java program accepts ... Read More

The subexpression/metacharacter “re*” matches 0 or more occurrences of the preceding expression.Example 1import java.util.regex.Matcher; import java.util.regex.Pattern; public class RegexExample {    public static void main( String args[] ) {       String regex = "aabc*";       String input = "aabcabcaabcabbcaabcbcaabc";       Pattern p = Pattern.compile(regex);       Matcher m = p.matcher(input);       int count = 0;       while(m.find()) {          count++;       }       System.out.println("Number of matches: "+count);    } }OutputNumber of matches: 4Example 2import java.util.Scanner; import java.util.regex.Matcher; import java.util.regex.Pattern; public class MatchAllCharacters ... Read More

The @ConstructorProperties annotation is from java.beans package, used to deserialize JSON to java object via the annotated constructor. This annotation supports from Jackson 2.7 version onwards. The way this annotation works very simple, rather than annotating each parameter in the constructor, we can provide an array with the properties names for each of the constructor parameters.Syntax@Documented @Target(value=CONSTRUCTOR) @Retention(value=RUNTIME) public @interface ConstructorPropertiesExampleimport com.fasterxml.jackson.databind.ObjectMapper; import java.beans.ConstructorProperties; public class ConstructorPropertiesAnnotationTest {    public static void main(String args[]) throws Exception {       ObjectMapper mapper = new ObjectMapper();       Employee emp = new Employee(115, "Raja");       String jsonString = mapper.writerWithDefaultPrettyPrinter().writeValueAsString(emp);   ... Read More