AddDashBeforeAndAfterEveryVowel
public class AddDashBeforeAndAfterEveryVowel {
public static void main(String[] args) {
// TODO Auto-generated method stub
String text = "C++";
System.out.println("Original string: "+text);
System.out.println("Add a dash before and after every vowel in the said
string: "+validate(text));
text = "Java";
System.out.println("\nOriginal string: "+text);
System.out.println("Add a dash before and after every vowel in the said
string: "+validate(text));
text = "MID-CENTRALIZED";
System.out.println("\nOriginal string: "+text);
System.out.println("Add a dash before and after every vowel in the said
string: "+validate(text));
text = "LOWERED";
System.out.println("\nOriginal string: "+text);
System.out.println("Add a dash before and after every vowel in the said
string: "+validate(text));
}
public static String validate(String txt) {
return txt.replaceAll("([AEIOUaeiou])","-$1-");
}
}
AddDashBetweenUpperAndLowerCaseLetter
public class AddDashBetweenUpperAndLowerCaseLetter {
public static void main(String[] args) {
// TODO Auto-generated method stub
String text = "Python Exercises";
System.out.println("Original string: "+text);
System.out.println("Insert a dash between an upper case letter and a
lower case letter in the said string:\n"+validate(text));
text = "The quick brown Fox jumps over the lazy Dog.";
System.out.println("\nOriginal string: "+text);
System.out.println("Insert a dash between an upper case letter and a
lower case letter in the said string:\n"+validate(text));
text = "java exercises";
System.out.println("\nOriginal string: "+text);
System.out.println("Insert a dash between an upper case letter and a
lower case letter in the said string:\n"+validate(text));
}
public static String validate(String txt) {
return txt.replaceAll("(?<=[A-Z])(?=[a-z])","-");
}
}
CheckAWordContainingTheCharacterGInAGivenString
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class CheckAWordContainingTheCharacterGInAGivenString {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("obulipurusothaman"));
System.out.println(validate("gopalchettiyar"));
System.out.println(validate("gokul"));
}
public static String validate(String txt) {
Pattern pattern=Pattern.compile("\\w*g.\\w*");
Matcher m=pattern.matcher(txt);
if(m.find()) {
return "Match found";
}
else {
return "Not found";
}
}
}
CheckForANumberAtTheEndOfAString
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class CheckForANumberAtTheEndOfAString {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("19CS094"));
System.out.println(validate("OBULIPURUSOTHAMAN"));
System.out.println(validate("01.102.103.104"));
}
public static String validate(String txt) {
Pattern pattern=Pattern.compile(".*[0-9]$");
Matcher m=pattern.matcher(txt);
if(m.find())
return "Match found";
else
return "Not found";
}
}
CheckTheStringContainsOnlyACertainSetOfCharacters
public class CheckTheStringContainsOnlyACertainSetOfCharacters {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("obuli"));
System.out.println(validate("19CS094"));
System.out.println(validate("*()&^%$#@"));
System.out.println(validate("936171"));
System.out.println(validate("google.com"));
}
public static boolean validate(String txt) {
return txt.matches("^[\\w]+$");
}
}
CheckTheStringStartsWithASpecificNumbersOrNot
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class CheckTheStringStartsWithASpecificNumbersOrNot {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("592838383"));
System.out.println(validate("5-12345-1923738"));
System.out.println(validate("19cs094"));
System.out.println(validate("637412"));
}
public static String validate(String txt) {
Pattern pattern=Pattern.compile("^5.*$");
Matcher m=pattern.matcher(txt);
if(m.find())
return "Match found";
else
return "Not Found";
}
}
CountNoOfVowelsInAString
import java.util.*;
public class CountNoOfVowelsInAString {
public static void main(String[] args) {
// TODO Auto-generated method stub
String a="C++";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="java";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="python";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="obulipurusothaman";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="JAVA";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="OBULIPURUSOTHAMAN";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
}
public static int validate(String txt) {
return txt.replaceAll("[^aeiouAEIOU]","").length();
}
}
CountTheNumberOfDecimalPlacesInAGivenNumber
public class CountTheNumberOfDecimalPlacesInAGivenNumber {
public static void main(String[] args) {
// TODO Auto-generated method stub
String a="122";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
a="128.0447";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
a="111.111";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
a="303";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
a="40.403";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
a="122";
System.out.println("the original string is:"+a);
System.out.println("decimal count is:"+validate(a));
}
public static Integer validate(String txt) {
if(txt.contains("."))
return txt.replaceAll(".*\\.(?=\\d?)", "").length();
return 0;
}
}
FindAStringThatHasAPFollowedByAnythingEndingInQ
public class FindAStringThatHasAPFollowedByAnythingEndingInQ {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("papaya"));
System.out.println(validate("pppqqqq"));
System.out.println(validate("pqqqqqqqqqqqq"));
System.out.println(validate("pq"));
}
public static String validate(String txt) {
if(txt.matches("p.*?q$")) {
return "Matches Found";
}
else {
return "No Matches";
}
}
}
FindSequenceOfOneUpperCaseLetterFollowedByLowerCaseLetters
public class FindSequenceOfOneUpperCaseLetterFollowedByLowerCaseLetters {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("obuli"));
System.out.println(validate("Obuli"));
System.out.println(validate("OBULI"));
System.out.println(validate("OB"));
System.out.println(validate("oB"));
System.out.println(validate("Ob"));
}
public static String validate(String txt) {
if(txt.matches("[A-Z][a-z]+$")) {
return "Matches Found";
}
else {
return "Not Matches";
}
}
}
FindTheSequenceOfLowerCaseLettersJoinedWithAUnderscore
public class FindTheSequenceOfLowerCaseLettersJoinedWithAUnderscore {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("Java_Programs"));
System.out.println(validate("java_exercises"));
System.out.println(validate("JAVA_EXCERISE"));
System.out.println(validate("java_examples"));
System.out.println(validate("JAVA_EXAMPLES"));
}
public static String validate(String txt) {
if(txt.matches("^[a-z]+_[a-z]+$")) {
return "Found a match";
}
else {
return "Not found";
}
}
}
GivenStringIsValidHexCodeOrNot
public class GivenStringIsValidHexCodeOrNot {
public static void main(String[] args) {
// TODO Auto-generated method stub
String text = "123456";
System.out.println("Original String: "+text);
System.out.println("Check the said string is a valid hex code or not? "
+validate(text));
text = "#eaecff";
System.out.println("\nOriginal String: "+text);
System.out.println("Check the said string is a valid hex code or not? "
+validate(text));
text = "#FF0000";
System.out.println("\nOriginal String: "+text);
System.out.println("Check the said string is a valid hex code or not? "
+validate(text));
text = "#DD5C5C";
System.out.println("\nOriginal String: "+text);
System.out.println("Check the said string is a valid hex code or not? "
+validate(text));
text = "#0000000";
System.out.println("\nOriginal String: "+text);
System.out.println("Check the said string is a valid hex code or not? "
+validate(text));
}
public static Boolean validate(String txt) {
return txt.matches("#[0-9A-Fa-f]{6}");
}
}
MatchAStringThatContainsOnlyUpperAndLowerCaseLttersNumbersAndUnderscores
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class MatchAStringThatContainsOnlyUpperAndLowerCaseLttersNumbersAndUnderscores{
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("obulipurusothaman"));
System.out.println(validate("OBULIPURUSOTHAMAN"));
System.out.println(validate("19CS094"));
}
public static String validate(String txt) {
Pattern pattern=Pattern.compile("^[a-zA-Z0-9]*$");
Matcher m=pattern.matcher(txt);
if(m.find())
return "Match Found";
else
return "Not Found";
}
}
MatchesAStringThatHasAPFollowedByZeroOrMoreQs
public class MatchesAStringThatHasAPFollowedByZeroOrMoreQs {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("p"));
System.out.println(validate("pq"));
System.out.println(validate("pqqq"));
System.out.println(validate("pqr"));
System.out.println(validate("psg"));
}
public static String validate(String a) {
if(a.matches("pq*?")){
return "Found a match";
}
else {
return "Not matched";
}
}
}
MoveAllTheLowerCaseToFront
public class MoveAllTheLowerCaseToFront {
public static void main(String[] args) {
// TODO Auto-generated method stub
String txt="Java";
System.out.println("the original string is:"+txt);
System.out.println("Move all lower case letters to the front of the said word: "
+validate(txt));
txt="JavaScript";
System.out.println("the original string is:"+txt);
System.out.println("Move all lower case letters to the front of the said word: "
+validate(txt));
txt="SqLite";
System.out.println("the original string is:"+txt);
System.out.println("Move all lower case letters to the front of the said word: "
+validate(txt));
}
public static String validate(String txt) {
return txt.replaceAll("[A-Z]","")+txt.replaceAll("[a-z]","");
}
}
RemoveAllTheVowelsOfAGivenStringAndReturnTheNewString
public class RemoveAllTheVowelsOfAGivenStringAndReturnTheNewString {
public static void main(String[] args) {
// TODO Auto-generated method stub
String a="C++";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="java";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="python";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="obulipurusothaman";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="JAVA";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
a="OBULIPURUSOTHAMAN";
System.out.println("the original string is:"+a);
System.out.println("no of vowels is:"+validate(a));
}
public static String validate(String txt) {
return txt.replaceAll("(?i)[aeiou]","");
}
}
RemoveLeadingZerosFromAGivenIPAddress
public class RemoveLeadingZerosFromAGivenIPAddress {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println(validate("216.08.094.196"));
System.out.println(validate("08.008.0008.00008"));
System.out.println(validate("01.102.103.104"));
}
public static String validate(String txt) {
return txt.replaceAll("(?<=^|\\.)0+(?!\\.|$)","");
}
}
ReplaceAllTheVowelsInAGivenStringWithASpecifiedCharacter
import java.util.*;
public class ReplaceAllTheVowelsInAGivenStringWithASpecifiedCharacter {
public static void main(String[] args) {
// TODO Auto-generated method stub
String a="C++";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'*'));
a="java";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'@'));
a="python";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'#'));
a="obulipurusothaman";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'@'));
a="JAVA";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'#'));
a="OBULIPURUSOTHAMAN";
System.out.println("the original string is:"+a);
System.out.println("replace vowels is:"+validate(a,'*'));
}
public static String validate(String txt,char c) {
return txt.replaceAll("[aeiouAEIOU]",""+ c);
}
}
ReplacePythonWithJavaAndCodeWithCodingInJava
public class ReplacePythonWithJavaAndCodeWithCodingInJava {
public static void main(String[] args) {
// TODO Auto-generated method stub
String text = "Python is an interpreted high-level general-purpose programming
language. " +
"Its design philosophy emphasizes code readability with its use of
significant indentation. " +
"Its language constructs as well as its object-oriented approach
aim to help programmers write" +
"clear, logical code for small and large-scale projects.";
System.out.println("the orginal string is:"+text);
System.out.println("the replaced string is:"+validate(text));
}
public static String validate(String txt) {
return txt.replace("Python","Java").replace("code","coding");
}
}
ReplaceWordInString
public class ReplaceWordInString {
public static void main(String[] args) {
// TODO Auto-generated method stub
String a="python";
System.out.println("the orginal string is:"+a);
System.out.println("the replaced string is:"+validate(a));
a="JavaScript";
System.out.println("the orginal string is:"+a);
System.out.println("the replaced string is:"+validate(a));
a="PYTHON";
System.out.println("the orginal string is:"+a);
System.out.println("the replaced string is:"+validate(a));
}
public static String validate(String txt) {
String a=txt.toLowerCase();
if(a.contains("python"))
return "Java";
else
return "C++";
}
}
SeperateConsonantsAndVowelsFromAGivenString
public class SeperateConsonantsAndVowelsFromAGivenString {
public static void main(String[] args) {
// TODO Auto-generated method stub
String txt="Java";
System.out.println("the original string is:"+txt);
System.out.println("Separate consonants and vowels of the said string: "
+validate(txt));
txt="JavaScript";
System.out.println("the original string is:"+txt);
System.out.println("Separate consonants and vowels of the said string: "
+validate(txt));
txt="SqLite";
System.out.println("the original string is:"+txt);
System.out.println("Separate consonants and vowels of the said string: "
+validate(txt));
}
public static String validate(String txt) {
String a=txt.replaceAll("(?i)[^aeiou]","");
String b=txt.replaceAll("(?i)[aeiou]","");
return a+b;
}
}
SetThousandsSeperatorInTheSaidNumber
public class SetThousandsSeperatorInTheSaidNumber {
public static void main(String[] args) {
// TODO Auto-generated method stub
int n = 100;
System.out.println("Original Number: "+n);
System.out.println("Set thousands separator in the said number): "
+validate(n));
n = 1000;
System.out.println("\nOriginal Number: "+n);
System.out.println("Set thousands separator in the said number): "
+validate(n));
n = 10000;
System.out.println("\nOriginal Number: "+n);
System.out.println("Set thousands separator in the said number): "
+validate(n));
n = 100000;
System.out.println("\nOriginal Number: "+n);
System.out.println("Set thousands separator in the said number): "
+validate(n));
n = 1000000;
System.out.println("\nOriginal Number: "+n);
System.out.println("Set thousands separator in the said number): "
+validate(n));
}
public static String validate(int num) {
String b=Integer.toString(num);
int len=b.length();
if(len<4) {
return b;
}
return validate(Integer.parseInt(b.substring(0, len-3))) + '#' +
b.substring(len-3);
}
}
ValidateAPersonalIdentificationNumberPIN
public class ValidateAPersonalIdentificationNumberPIN {
public static void main(String[] args) {
// TODO Auto-generated method stub
String n = "123";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "1234";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "12345";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "123456";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "1234567";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "12345678";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
n = "123456789";
System.out.println("Original PIN Number: "+n);
System.out.println("Is the said PIN number is valid? "+validate(n));
}
public static boolean validate(String txt) {
return txt.matches("\\d{4}\\d{6}\\d{8}");
}
}
ValidatePhoneNumber
public class ValidatePhoneNumber {
public static void main(String[] args) {
// TODO Auto-generated method stub
String text ="(123)4567890";
System.out.println("Original Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "+validate(text));
text ="(123)4567890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="1234567890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="123-456-7890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="(1234567890)";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="123)4567890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="12345678901";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="(1)234567890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="(123)-4567890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="1";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="12-3456-7890";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
text ="123-4567";
System.out.println("\nOriginal Phone number: "+text);
System.out.println("Check the said Phone number is true or not! "
+validate(text));
}
public static Boolean validate(String txt) {
return txt.matches("\\d{10}|(?:\\d{3}-){2}\\d{4}|\\(\\d{3}\\)\\d{3}-?\\d{4}");
}
}