Hello everyone im trying to make a code to remove
vowels and consonants when a user types a string
but i seem to fail at the code and i need to use a stack class to do it
Sample Output should be like this and will ignore non alphabet characters
Enter a String : hello1234!##$
Vowels : eo
Consonant : hll
Final contents : 1234!##$
can someone fix my code
this is the error I get
enter image description here
import java.util.Scanner;
import java.util.Stack;
public class PushPop
{
//I used the push and pop methods
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.print("Enter a String: ");
String str = sc.nextLine();
Stack<String> String = new Stack();
String.push(str);
String vowels = String.pop();
vowels = vowels.replace("[aeiou]", "");
String consonants = String.pop();
consonants = consonants.replace("[qbcdfghjklmnpqrstvwxyz]", "");
System.out.println("Vowels: "+ vowels);
System.out.print("Consonant: "+ consonants);
//this will print what is left after popping the elements
System.out.print("Final contents: "+ str);
}
}
If you just want to remove all vowels and consonants form the user's input, a Stack is not needed (at least if you use the ready made Java's Pattern in some way). In fact, you get the Exception because you try to pop from the Stack twice, while having only pushed once. In particular you first push the user's input str, then pop it to the variable vowels (so the Stack is now empty) and then you pop from it again, this time into the variable consonants.
vowels = vowels.replace("[aeiou]", "");
According to documentation of replace it will replace all literals with the second argument. This means that it will replace all Strings matching the literal "[aeiou]" (if it exists as is in the user's input) with the empty String. Instead you should use replaceAll method which takes a regex (ie Regular Expression) as the first argument:
str = str.replaceAll("[aeiou]", "");
The regular expressions you are using seem correct for your problem, although you want to first remove the vowels from the user's input and then from that String (which is the result of the user's input by removing all vowels) remove also the consonants. So the logic should instead be:
String str = sc.nextLine(); //Get user input.
str = str.replaceAll("[aeiou]", ""); //Remove vowels.
str = str.replaceAll("[qbcdfghjklmnpqrstvwxyz]", ""); //Remove consonants.
System.out.println(str); //Print result.
which, if you combine the two regexes toghether in a single operation, can be shortened to:
String str = sc.nextLine();
str = str.replaceAll("[aeiouqbcdfghjklmnpqrstvwxyz]", "");
System.out.println(str);
which, if you realize that these are all alphabet letters, can be shortened even further with:
str = str.replaceAll("[a-z]", "");
and if you also want both upper and lower case letters, then you can do:
str = str.replaceAll("[a-zA-Z]", "");
which is equivalent to:
str = str.replaceAll("\\p{Alpha}", "");
All those examples can be made clear for someone if they read the documentation on how a Java Pattern is constructed, so it may help to take a look there, if you didn't already know it.
i need to use a stack class to do it
Can you please explain what is the desired behaviour, and how a Stack needs to be used? Because it seems like you just want to remove all alphabet letters. Are you required to not use regexes for this?
I want to split the string "004-034556" into two strings by the delimiter "-":
part1 = "004";
part2 = "034556";
That means the first string will contain the characters before '-', and the second string will contain the characters after '-'.
I also want to check if the string has '-' in it.
Use the appropriately named method String#split().
String string = "004-034556";
String[] parts = string.split("-");
String part1 = parts[0]; // 004
String part2 = parts[1]; // 034556
Note that split's argument is assumed to be a regular expression, so remember to escape special characters if necessary.
there are 12 characters with special meanings: the backslash \, the caret ^, the dollar sign $, the period or dot ., the vertical bar or pipe symbol |, the question mark ?, the asterisk or star *, the plus sign +, the opening parenthesis (, the closing parenthesis ), and the opening square bracket [, the opening curly brace {, These special characters are often called "metacharacters".
For instance, to split on a period/dot . (which means "any character" in regex), use either backslash \ to escape the individual special character like so split("\\."), or use character class [] to represent literal character(s) like so split("[.]"), or use Pattern#quote() to escape the entire string like so split(Pattern.quote(".")).
String[] parts = string.split(Pattern.quote(".")); // Split on the exact string.
To test beforehand if the string contains certain character(s), just use String#contains().
if (string.contains("-")) {
// Split it.
} else {
throw new IllegalArgumentException("String " + string + " does not contain -");
}
Note, this does not take a regular expression. For that, use String#matches() instead.
If you'd like to retain the split character in the resulting parts, then make use of positive lookaround. In case you want to have the split character to end up in left hand side, use positive lookbehind by prefixing ?<= group on the pattern.
String string = "004-034556";
String[] parts = string.split("(?<=-)");
String part1 = parts[0]; // 004-
String part2 = parts[1]; // 034556
In case you want to have the split character to end up in right hand side, use positive lookahead by prefixing ?= group on the pattern.
String string = "004-034556";
String[] parts = string.split("(?=-)");
String part1 = parts[0]; // 004
String part2 = parts[1]; // -034556
If you'd like to limit the number of resulting parts, then you can supply the desired number as 2nd argument of split() method.
String string = "004-034556-42";
String[] parts = string.split("-", 2);
String part1 = parts[0]; // 004
String part2 = parts[1]; // 034556-42
An alternative to processing the string directly would be to use a regular expression with capturing groups. This has the advantage that it makes it straightforward to imply more sophisticated constraints on the input. For example, the following splits the string into two parts, and ensures that both consist only of digits:
import java.util.regex.Pattern;
import java.util.regex.Matcher;
class SplitExample
{
private static Pattern twopart = Pattern.compile("(\\d+)-(\\d+)");
public static void checkString(String s)
{
Matcher m = twopart.matcher(s);
if (m.matches()) {
System.out.println(s + " matches; first part is " + m.group(1) +
", second part is " + m.group(2) + ".");
} else {
System.out.println(s + " does not match.");
}
}
public static void main(String[] args) {
checkString("123-4567");
checkString("foo-bar");
checkString("123-");
checkString("-4567");
checkString("123-4567-890");
}
}
As the pattern is fixed in this instance, it can be compiled in advance and stored as a static member (initialised at class load time in the example). The regular expression is:
(\d+)-(\d+)
The parentheses denote the capturing groups; the string that matched that part of the regexp can be accessed by the Match.group() method, as shown. The \d matches and single decimal digit, and the + means "match one or more of the previous expression). The - has no special meaning, so just matches that character in the input. Note that you need to double-escape the backslashes when writing this as a Java string. Some other examples:
([A-Z]+)-([A-Z]+) // Each part consists of only capital letters
([^-]+)-([^-]+) // Each part consists of characters other than -
([A-Z]{2})-(\d+) // The first part is exactly two capital letters,
// the second consists of digits
Use:
String[] result = yourString.split("-");
if (result.length != 2)
throw new IllegalArgumentException("String not in correct format");
This will split your string into two parts. The first element in the array will be the part containing the stuff before the -, and the second element in the array will contain the part of your string after the -.
If the array length is not 2, then the string was not in the format: string-string.
Check out the split() method in the String class.
This:
String[] out = string.split("-");
should do the thing you want. The string class has many method to operate with a string.
// This leaves the regexes issue out of question
// But we must remember that each character in the Delimiter String is treated
// like a single delimiter
public static String[] SplitUsingTokenizer(String subject, String delimiters) {
StringTokenizer strTkn = new StringTokenizer(subject, delimiters);
ArrayList<String> arrLis = new ArrayList<String>(subject.length());
while(strTkn.hasMoreTokens())
arrLis.add(strTkn.nextToken());
return arrLis.toArray(new String[0]);
}
With Java 8:
List<String> stringList = Pattern.compile("-")
.splitAsStream("004-034556")
.collect(Collectors.toList());
stringList.forEach(s -> System.out.println(s));
Use org.apache.commons.lang.StringUtils' split method which can split strings based on the character or string you want to split.
Method signature:
public static String[] split(String str, char separatorChar);
In your case, you want to split a string when there is a "-".
You can simply do as follows:
String str = "004-034556";
String split[] = StringUtils.split(str,"-");
Output:
004
034556
Assume that if - does not exists in your string, it returns the given string, and you will not get any exception.
The requirements left room for interpretation. I recommend writing a method,
public final static String[] mySplit(final String s)
which encapsulate this function. Of course you can use String.split(..) as mentioned in the other answers for the implementation.
You should write some unit-tests for input strings and the desired results and behaviour.
Good test candidates should include:
- "0022-3333"
- "-"
- "5555-"
- "-333"
- "3344-"
- "--"
- ""
- "553535"
- "333-333-33"
- "222--222"
- "222--"
- "--4555"
With defining the according test results, you can specify the behaviour.
For example, if "-333" should return in [,333] or if it is an error.
Can "333-333-33" be separated in [333,333-33] or [333-333,33] or is it an error? And so on.
To summarize: there are at least five ways to split a string in Java:
String.split():
String[] parts ="10,20".split(",");
Pattern.compile(regexp).splitAsStream(input):
List<String> strings = Pattern.compile("\\|")
.splitAsStream("010|020202")
.collect(Collectors.toList());
StringTokenizer (legacy class):
StringTokenizer strings = new StringTokenizer("Welcome to EXPLAINJAVA.COM!", ".");
while(strings.hasMoreTokens()){
String substring = strings.nextToken();
System.out.println(substring);
}
Google Guava Splitter:
Iterable<String> result = Splitter.on(",").split("1,2,3,4");
Apache Commons StringUtils:
String[] strings = StringUtils.split("1,2,3,4", ",");
So you can choose the best option for you depending on what you need, e.g. return type (array, list, or iterable).
Here is a big overview of these methods and the most common examples (how to split by dot, slash, question mark, etc.)
You can try like this also
String concatenated_String="hi^Hello";
String split_string_array[]=concatenated_String.split("\\^");
Assuming, that
you don't really need regular expressions for your split
you happen to already use apache commons lang in your app
The easiest way is to use StringUtils#split(java.lang.String, char). That's more convenient than the one provided by Java out of the box if you don't need regular expressions. Like its manual says, it works like this:
A null input String returns null.
StringUtils.split(null, *) = null
StringUtils.split("", *) = []
StringUtils.split("a.b.c", '.') = ["a", "b", "c"]
StringUtils.split("a..b.c", '.') = ["a", "b", "c"]
StringUtils.split("a:b:c", '.') = ["a:b:c"]
StringUtils.split("a b c", ' ') = ["a", "b", "c"]
I would recommend using commong-lang, since usually it contains a lot of stuff that's usable. However, if you don't need it for anything else than doing a split, then implementing yourself or escaping the regex is a better option.
For simple use cases String.split() should do the job. If you use guava, there is also a Splitter class which allows chaining of different string operations and supports CharMatcher:
Splitter.on('-')
.trimResults()
.omitEmptyStrings()
.split(string);
The fastest way, which also consumes the least resource could be:
String s = "abc-def";
int p = s.indexOf('-');
if (p >= 0) {
String left = s.substring(0, p);
String right = s.substring(p + 1);
} else {
// s does not contain '-'
}
String Split with multiple characters using Regex
public class StringSplitTest {
public static void main(String args[]) {
String s = " ;String; String; String; String, String; String;;String;String; String; String; ;String;String;String;String";
//String[] strs = s.split("[,\\s\\;]");
String[] strs = s.split("[,\\;]");
System.out.println("Substrings length:"+strs.length);
for (int i=0; i < strs.length; i++) {
System.out.println("Str["+i+"]:"+strs[i]);
}
}
}
Output:
Substrings length:17
Str[0]:
Str[1]:String
Str[2]: String
Str[3]: String
Str[4]: String
Str[5]: String
Str[6]: String
Str[7]:
Str[8]:String
Str[9]:String
Str[10]: String
Str[11]: String
Str[12]:
Str[13]:String
Str[14]:String
Str[15]:String
Str[16]:String
But do not expect the same output across all JDK versions. I have seen one bug which exists in some JDK versions where the first null string has been ignored. This bug is not present in the latest JDK version, but it exists in some versions between JDK 1.7 late versions and 1.8 early versions.
There are only two methods you really need to consider.
Use String.split for a one-character delimiter or you don't care about performance
If performance is not an issue, or if the delimiter is a single character that is not a regular expression special character (i.e., not one of .$|()[{^?*+\) then you can use String.split.
String[] results = input.split(",");
The split method has an optimization to avoid using a regular expression if the delimeter is a single character and not in the above list. Otherwise, it has to compile a regular expression, and this is not ideal.
Use Pattern.split and precompile the pattern if using a complex delimiter and you care about performance.
If performance is an issue, and your delimiter is not one of the above, you should pre-compile a regular expression pattern which you can then reuse.
// Save this somewhere
Pattern pattern = Pattern.compile("[,;:]");
/// ... later
String[] results = pattern.split(input);
This last option still creates a new Matcher object. You can also cache this object and reset it for each input for maximum performance, but that is somewhat more complicated and not thread-safe.
You can split a string by a line break by using the following statement:
String textStr[] = yourString.split("\\r?\\n");
You can split a string by a hyphen/character by using the following statement:
String textStr[] = yourString.split("-");
public class SplitTest {
public static String[] split(String text, String delimiter) {
java.util.List<String> parts = new java.util.ArrayList<String>();
text += delimiter;
for (int i = text.indexOf(delimiter), j=0; i != -1;) {
String temp = text.substring(j,i);
if(temp.trim().length() != 0) {
parts.add(temp);
}
j = i + delimiter.length();
i = text.indexOf(delimiter,j);
}
return parts.toArray(new String[0]);
}
public static void main(String[] args) {
String str = "004-034556";
String delimiter = "-";
String result[] = split(str, delimiter);
for(String s:result)
System.out.println(s);
}
}
Please don't use StringTokenizer class as it is a legacy class that is retained for compatibility reasons, and its use is discouraged in new code. And we can make use of the split method as suggested by others as well.
String[] sampleTokens = "004-034556".split("-");
System.out.println(Arrays.toString(sampleTokens));
And as expected it will print:
[004, 034556]
In this answer I also want to point out one change that has taken place for split method in Java 8. The String#split() method makes use of Pattern.split, and now it will remove empty strings at the start of the result array. Notice this change in documentation for Java 8:
When there is a positive-width match at the beginning of the input
sequence then an empty leading substring is included at the beginning
of the resulting array. A zero-width match at the beginning however
never produces such empty leading substring.
It means for the following example:
String[] sampleTokensAgain = "004".split("");
System.out.println(Arrays.toString(sampleTokensAgain));
we will get three strings: [0, 0, 4] and not four as was the case in Java 7 and before. Also check this similar question.
One way to do this is to run through the String in a for-each loop and use the required split character.
public class StringSplitTest {
public static void main(String[] arg){
String str = "004-034556";
String split[] = str.split("-");
System.out.println("The split parts of the String are");
for(String s:split)
System.out.println(s);
}
}
Output:
The split parts of the String are:
004
034556
import java.io.*;
public class BreakString {
public static void main(String args[]) {
String string = "004-034556-1234-2341";
String[] parts = string.split("-");
for(int i=0;i<parts.length;i++) ｛
System.out.println(parts[i]);
}
}
}
You can use Split():
import java.io.*;
public class Splitting
{
public static void main(String args[])
{
String Str = new String("004-034556");
String[] SplittoArray = Str.split("-");
String string1 = SplittoArray[0];
String string2 = SplittoArray[1];
}
}
Else, you can use StringTokenizer:
import java.util.*;
public class Splitting
{
public static void main(String[] args)
{
StringTokenizer Str = new StringTokenizer("004-034556");
String string1 = Str.nextToken("-");
String string2 = Str.nextToken("-");
}
}
Here are two ways two achieve it.
WAY 1: As you have to split two numbers by a special character you can use regex
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class TrialClass
{
public static void main(String[] args)
{
Pattern p = Pattern.compile("[0-9]+");
Matcher m = p.matcher("004-034556");
while(m.find())
{
System.out.println(m.group());
}
}
}
WAY 2: Using the string split method
public class TrialClass
{
public static void main(String[] args)
{
String temp = "004-034556";
String [] arrString = temp.split("-");
for(String splitString:arrString)
{
System.out.println(splitString);
}
}
}
You can simply use StringTokenizer to split a string in two or more parts whether there are any type of delimiters:
StringTokenizer st = new StringTokenizer("004-034556", "-");
while(st.hasMoreTokens())
{
System.out.println(st.nextToken());
}
Check out the split() method in the String class on javadoc.
https://docs.oracle.com/javase/7/docs/api/java/lang/String.html#split(java.lang.String)
String data = "004-034556-1212-232-232";
int cnt = 1;
for (String item : data.split("-")) {
System.out.println("string "+cnt+" = "+item);
cnt++;
}
Here many examples for split string but I little code optimized.
String str="004-034556"
String[] sTemp=str.split("-");// '-' is a delimiter
string1=004 // sTemp[0];
string2=034556//sTemp[1];
I just wanted to write an algorithm instead of using Java built-in functions:
public static List<String> split(String str, char c){
List<String> list = new ArrayList<>();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < str.length(); i++){
if(str.charAt(i) != c){
sb.append(str.charAt(i));
}
else{
if(sb.length() > 0){
list.add(sb.toString());
sb = new StringBuilder();
}
}
}
if(sb.length() >0){
list.add(sb.toString());
}
return list;
}
You can use the method split:
public class Demo {
public static void main(String args[]) {
String str = "004-034556";
if ((str.contains("-"))) {
String[] temp = str.split("-");
for (String part:temp) {
System.out.println(part);
}
}
else {
System.out.println(str + " does not contain \"-\".");
}
}
}
To split a string, uses String.split(regex). Review the following examples:
String data = "004-034556";
String[] output = data.split("-");
System.out.println(output[0]);
System.out.println(output[1]);
Output
004
034556
Note:
This split (regex) takes a regex as an argument. Remember to escape the regex special characters, like period/dot.
String s = "TnGeneral|DOMESTIC";
String a[]=s.split("\\|");
System.out.println(a.toString());
System.out.println(a[0]);
System.out.println(a[1]);
Output:
TnGeneral
DOMESTIC
String s="004-034556";
for(int i=0;i<s.length();i++)
{
if(s.charAt(i)=='-')
{
System.out.println(s.substring(0,i));
System.out.println(s.substring(i+1));
}
}
As mentioned by everyone, split() is the best option which may be used in your case. An alternative method can be using substring().
I want to make everything the user enters capitalized and certain letters to be replaced with numbers or symbols. Im trying to utilize .replace but something is not going right. Im not sure what im doing wrong?
public class Qbert
{
public static void main(String[] args)
{
//variables
String str;
//get input
Scanner kb = new Scanner(System.in);
System.out.print(" Please Enter a Word:");
//accept input
str = kb.nextLine();
System.out.print("" );
System.out.println(str.toUpperCase()//make all letters entered uppercase
//sort specific letters to make them corresponding number, letter, or symbol
+ str.replace("A,#")+ str.replaceChar("E","3")+ str.replaceChar ("G","6")
+ str.replaceChar("I","!")+ str.replaceChar("S","$")+ str.replaceChar ("T","7"));
}
}
In Java, Strings are immutable. This means that modifying a string will result in a new string. E.g.
str.replace("a", "b");
this will replace all the occurrences of 'a' to 'b' in a new string. Original string will remain unaffected. So, to apply the formatting on the actual string, we will have to write:
str = str.replace("a", "b");
Similarly, if we want to do multiple replacements then, we need to append replace calls together, e.g.
str = str.replace("a","b").replace("c", "d");
Going by this, if you want to perform the substitution, the last system.out in your code will be:
System.out.println(str.toUpperCase().replace("A","#").replace("E","3")
.replace("G","6").replace("I","!").replace("S","$").replace("T","7"));
String doesn't have a replaceChar method. You probably wanted to use method replace.
And String.replace() takes 2 arguments:
public String replace(CharSequence target, CharSequence replacement)
Replaces each substring of this string that matches the literal target
sequence with the specified literal replacement sequence. The
replacement proceeds from the beginning of the string to the end, for
example, replacing "aa" with "b" in the string "aaa" will result in
"ba" rather than "ab".
You have written str.replace("A,#")+... instead of str.replace("A","#")+..., and so on
One more thing - use a good IDE like Eclipse or Intellij IDEA, they will highlight the parts of your code where you have errors.
public static void main(String... args) {
// variables
String str;
// get input
Scanner kb = new Scanner(System.in);
System.out.print(" Please Enter a Word:");
// accept input
str = kb.nextLine();
System.out.print("");
System.out.println(str.toUpperCase()); // Upper Case
System.out.println(str.toUpperCase().replace("A", "#").replace("E", "3")
.replace("E", "3").replace("G", "6").replace("I", "!").replace("S", "$").replace("T", "7") );
}
This should work like you want it to. Hope you find this helpful.
As you want to make multiple changes to the same string, you just use
str.toUpperCase().replace().replace().... This means you are giving
the output of str.toUpperCase() to the first replace function and so
on...
System.out.println(str.toUpperCase()
.replace("A","#")
.replace("E","3")
.replace("G","6")
.replace("I","!")
.replace("S","$")
.replace("T","7"));
I would like to find same word in two string.
startpoint = newresult.indexOf('\'');
endpoint = newresult.lastIndexOf('\'');
variables = newresult.substring(startpoint, endpoint);
variables = variables.replace("\r\n", ",");
variables = variables.replaceAll("'", "");`
String variables:
cons,john,$,alex,manag;
String second:
ins_manages(john,cons)
As it is seen, both strings they have john and cons and I want to check if both have same char sequences or not but I don't know how it can be checked? Is there any way to check it directly?
Solution:
String [] newvar;
newvar = variables.split(",");
After that, I used a for loop and matched them one by one.
BR
Split both the strings and compare the individual words using foreach as shown below:
String first = "hello world today";
String second = "Yet another hello worldly day today";
//split the second string into words
List<String> wordsOfSecond = Arrays.asList(second.split(" "));
//split and compare each word of the first string
for (String word : first.split(" ")) {
if(wordsOfSecond.contains(word))
System.out.println(word);
}
Your requirements are a little ambiguous. You're asking to find the same singular word in two strings, then your sample asks for finding two words in the same strings.
For verifying that one single word is in two strings, you can just do:
public boolean bothStringsContainWord(String s1, String s2, String word) {
return s1.contains(word) && s2.contians(word);
}
You can put that in a loop if you need to do it over multiple words. Again, your requirements are a little fuzzy though; if you straighten them up a more efficient solution probably exists.