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finding out if the characters of a string exist in another string with the same order or not using regex in java

i want to write a program in java using REGEX that gets 2 strings from the input ( the first one is shorter than the second one ) and then if the characters of the first string was inside the second string with the same order but they do not need to be next to each other ( it is not substring ) it outputs "true" and if not it outputs "false" here's an example:
example1:
input:
phantom
pphvnbajknzxcvbnatopopoim
output:
true
in the above example it is obvious we can see the word "phantom" in the second string (the characters are in the same order)
example2:
input:
apple
fgayiypvbnltsrgte
output:
false
as you can see apple dos not exists in the second string with the conditions i have earlier mentioned so it outputs false
import java.util.Scanner;
public class Main {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
String word1 = input.next();
String word2 = input.next();
String pattern = "";
int n = word1.length();
char[] word1CharArr = word1.toCharArray();
for ( int i = 0 ; i < n ; i++) {
pattern += "[:alnum:]" +word1CharArr[i]+"[:alnum:]";
// pattern += ".*\\b|\\B" +word1CharArr[i]+"\\b|\\B";
}
pattern = "^" + pattern + "$";
// pattern = "(?s)" + pattern + ".*";
// System.out.println(pattern);
System.out.println(word2.matches(pattern));
}
}
here is what i did . i broke my first string to its characters and want to use REGEX before and after each character to determine the pattern. I have searched much about REGEX and how to use it but still i have problem here. the part i have commented comes out from one of my searches but it did not work
I emphasize that i want to solve it with REGEX not any other way.

[:alnum:] isn't a thing. Even if it is, that would match exactly one character, not 'any number, from 0 to infinitely many of them'.
You just want phantom with .* in the middle: ^.*p.*h.*a.*n.*t.*o.*m.*$' is all you need. After all, phantom` 'fits', and so does paahaanaataaoaamaa -
String pattern = word1.chars()
.mapToObj(c -> ".*" + (char) c)
.collect(Collectors.joining()) + ".*";
should get the job done.

Get certain data from text - Java

I am creating a bukkit plugin for minecraft and i need to know a few things before i move on.
I want to check if a text has this layout: "B:10 S:5" for example.
It stands for Buy:amount and Sell:amount
How can i check the easiest way if it follows the syntax?
It can be any number that is 0 or over.
Another problem is to get this data out of the text. how can i check what text is after B: and S: and return it as an integer
I have not tried out this yet because i have no idea where to start.
Thanks for help!

In the simple problem you gave, you can get away with a simple answer. Otherwise, see the regex answer below.
boolean test(String str){
try{
//String str = "B:10 S:5";
String[] arr = str.split(" ");//split to left and right of space = [B:10,S:5]
String[] bArr = arr[0].split(":");//split ...first colon = [B,10]
String[] sArr = arr[1].split(":");//... second colon = [S,5]
//need to use try/catch here in case the string is not an int value.
String labelB = bArr[0];
Integer b = Integer.parseInt(bArr[1]);
String labelS = sArr[0];
Integer s = Integer.parseInt(sArr[1]);
}catch( Exception e){return false;}
return true;
}
See my answer here for a related task. More related details below.
How can I parse a string for a set?
Essentially, you need to use regex and iterate through the groups. Just in case the grammar is not always B and S, I made this more abstract.Also, if there are extra white spaces in the middle for what ever reason, I made that more broad too. The pattern says there are 4 groups (indicated by parentheses): label1, number1, label2, and number2. + means 1 or more. [] means a set of characters. a-z is a range of characters (don't put anything between A-Z and a-z). There are also other ways of showing alpha and numeric patterns, but these are easier to read.
//this is expensive
Pattern p=Pattern.compile("([A-Za-z]+):([0-9]+)[ ]+([A-Za-z]+):([0-9]+)");
boolean test(String txt){
Matcher m=p.matcher(txt);
if(!m.matches())return false;
int groups=m.groupCount();//should only equal 5 (default whole match+4 groups) here, but you can test this
System.out.println("Matched: " + m.group(0));
//Label1 = m.group(1);
//val1 = m.group(2);
//Label2 = m.group(3);
//val2 = m.group(4);
return true;
}

Use Regular Expression.
In your case,^B:(\d)+ S:(\d)+$ is enough.
In java, to use a regular expression:
public class RegExExample {
public static void main(String[] args) {
Pattern p = Pattern.compile("^B:(\d)+ S:(\d)+$");
for (int i = 0; i < args.length; i++)
if (p.matcher(args[i]).matches())
System.out.println( "ARGUMENT #" + i + " IS VALID!")
else
System.out.println( "ARGUMENT #" + i + " IS INVALID!");
}
}
This sample program take inputs from command line, validate it against the pattern and print the result to STDOUT.

Split complex string with Regex in JAVA

I want to Split following strings to an array with Regex in JAVA but I don't know how to do.
string1="advmod(likes-4, also-3)" ==> advmod, likes, also
string2="nsubj(likes-4, dog24-2)" ==> bsubj, likes, dog24
string3="num(dog24-3, 8-2)" ==> num, dog24, 8
Please help me to do this work? how split the string like "num(dog24-3, 8-2)" in three tokens num, dog24 and 8 and then putting they to an string array.
Thanks a lot.

This is generic:
String string[] = {"advmod(likes-4, also-3)",// ==> advmod , likes , also
"nsubj(likes-4, dog24-2)",// ==> bsubj , likes , dog24
"num(dog24-3, 8-2)"};//==> num ,dog24 , 8
Pattern p = Pattern.compile("(\\w+)\\(([^-]+).*, ([^-]+)");
for (int i = 0; i < string.length; i++) {
Matcher m = p.matcher(string[i]);
while(m.find()) {
System.out.print(i+": ");
for(int j=1; j<= m.groupCount(); j++){
System.out.print(m.group(j));
if(j!=m.groupCount()) {
System.out.print(", ");
}
}
System.out.println("");
}
}
Hope this helps, it works for me.
This is the output:
0: advmod, likes, also
1: nsubj, likes, dog24
2: num, dog24, 8

For 3rd String
String re1="(num)"; // Word 1
String re2=".*?"; // Non-greedy match on filler
String re3="(dog24)"; // Alphanum 1
String re4=".*?"; // Non-greedy match on filler
String re5="(8)"; // Integer Number 1
Pattern p = Pattern.compile(re1+re2+re3+re4+re5,Pattern.CASE_INSENSITIVE | Pattern.DOTALL);
Matcher m = p.matcher(txt);
if (m.find())
{
String word1=m.group(1);
String alphanum1=m.group(2);
String int1=m.group(3);
System.out.print("("+word1.toString()+")"+"("+alphanum1.toString()+")"+"("+int1.toString()+")"+"\n");
}

You if you want to split, you could use this:
str.split("\\(|-[0-9]+(?:,\\s+|\\))");
ideone demo.

You really haven't described your grammar, but assuming that it's something like looks like a Java method or a Prolog statement, try
final static String TOKEN_CHARACTERS="[\w\d-]"
final Pattern p = Pattern.compile("^(" + TOKEN_CHARACTERS + "+)\((" + TOKEN_CHARACTERS + "+,\s*(" + TOKEN_CHARACTERS + ")\)$";
Then split on the -; I presume that it really is there for some reason, and it's not clear that it's always present (if so, you can change the pattern to hard-code the single - instead of considering it part of the token). If you allow additional space or such, adjust accordingly.

How to find a whole word in a String in Java?

I have a String that I have to parse for different keywords.
For example, I have the String:
"I will come and meet you at the 123woods"
And my keywords are
'123woods'
'woods'
I should report whenever I have a match and where. Multiple occurrences should also be accounted for.
However, for this one, I should get a match only on '123woods', not on 'woods'. This eliminates using String.contains() method. Also, I should be able to have a list/set of keywords and check at the same time for their occurrence. In this example, if I have '123woods' and 'come', I should get two occurrences. Method execution should be somewhat fast on large texts.
My idea is to use StringTokenizer but I am unsure if it will perform well. Any suggestions?

The example below is based on your comments. It uses a List of keywords, which will be searched in a given String using word boundaries. It uses StringUtils from Apache Commons Lang to build the regular expression and print the matched groups.
String text = "I will come and meet you at the woods 123woods and all the woods";
List<String> tokens = new ArrayList<String>();
tokens.add("123woods");
tokens.add("woods");
String patternString = "\\b(" + StringUtils.join(tokens, "|") + ")\\b";
Pattern pattern = Pattern.compile(patternString);
Matcher matcher = pattern.matcher(text);
while (matcher.find()) {
System.out.println(matcher.group(1));
}
If you are looking for more performance, you could have a look at StringSearch: high-performance pattern matching algorithms in Java.

Use regex + word boundaries as others answered.
"I will come and meet you at the 123woods".matches(".*\\b123woods\\b.*");
will be true.
"I will come and meet you at the 123woods".matches(".*\\bwoods\\b.*");
will be false.

Hope this works for you:
String string = "I will come and meet you at the 123woods";
String keyword = "123woods";
Boolean found = Arrays.asList(string.split(" ")).contains(keyword);
if(found){
System.out.println("Keyword matched the string");
}
http://codigounico.blogspot.com/

How about something like Arrays.asList(String.split(" ")).contains("xx")?
See String.split() and How can I test if an array contains a certain value.

Got a way to match Exact word from String in Android:
String full = "Hello World. How are you ?";
String one = "Hell";
String two = "Hello";
String three = "are";
String four = "ar";
boolean is1 = isContainExactWord(full, one);
boolean is2 = isContainExactWord(full, two);
boolean is3 = isContainExactWord(full, three);
boolean is4 = isContainExactWord(full, four);
Log.i("Contains Result", is1+"-"+is2+"-"+is3+"-"+is4);
Result: false-true-true-false
Function for match word:
private boolean isContainExactWord(String fullString, String partWord){
String pattern = "\\b"+partWord+"\\b";
Pattern p=Pattern.compile(pattern);
Matcher m=p.matcher(fullString);
return m.find();
}
Done

public class FindTextInLine {
String match = "123woods";
String text = "I will come and meet you at the 123woods";
public void findText () {
if (text.contains(match)) {
System.out.println("Keyword matched the string" );
}
}
}

Try to match using regular expressions. Match for "\b123wood\b", \b is a word break.

The solution seems to be long accepted, but the solution could be improved, so if someone has a similar problem:
This is a classical application for multi-pattern-search-algorithms.
Java Pattern Search (with Matcher.find) is not qualified for doing that. Searching for exactly one keyword is optimized in java, searching for an or-expression uses the regex non deterministic automaton which is backtracking on mismatches. In worse case each character of the text will be processed l times (where l is the sum of the pattern lengths).
Single pattern search is better, but not qualified, too. One will have to start the whole search for every keyword pattern. In worse case each character of the text will be processed p times where p is the number of patterns.
Multi pattern search will process each character of the text exactly once. Algorithms suitable for such a search would be Aho-Corasick, Wu-Manber, or Set Backwards Oracle Matching. These could be found in libraries like Stringsearchalgorithms or byteseek.
// example with StringSearchAlgorithms
AhoCorasick stringSearch = new AhoCorasick(asList("123woods", "woods"));
CharProvider text = new StringCharProvider("I will come and meet you at the woods 123woods and all the woods", 0);
StringFinder finder = stringSearch.createFinder(text);
List<StringMatch> all = finder.findAll();

A much simpler way to do this is to use split():
String match = "123woods";
String text = "I will come and meet you at the 123woods";
String[] sentence = text.split();
for(String word: sentence)
{
if(word.equals(match))
return true;
}
return false;
This is a simpler, less elegant way to do the same thing without using tokens, etc.

You can use regular expressions.
Use Matcher and Pattern methods to get the desired output

You can also use regex matching with the \b flag (whole word boundary).

To Match "123woods" instead of "woods" , use atomic grouping in regular expresssion.
One thing to be noted is that, in a string to match "123woods" alone , it will match the first "123woods" and exits instead of searching the same string further.
\b(?>123woods|woods)\b
it searches 123woods as primary search, once it got matched it exits the search.

Looking back at the original question, we need to find some given keywords in a given sentence, count the number of occurrences and know something about where. I don't quite understand what "where" means (is it an index in the sentence?), so I'll pass that one... I'm still learning java, one step at a time, so I'll see to that one in due time :-)
It must be noticed that common sentences (as the one in the original question) can have repeated keywords, therefore the search cannot just ask if a given keyword "exists or not" and count it as 1 if it does exist. There can be more then one of the same. For example:
// Base sentence (added punctuation, to make it more interesting):
String sentence = "Say that 123 of us will come by and meet you, "
+ "say, at the woods of 123woods.";
// Split it (punctuation taken in consideration, as well):
java.util.List<String> strings =
java.util.Arrays.asList(sentence.split(" |,|\\."));
// My keywords:
java.util.ArrayList<String> keywords = new java.util.ArrayList<>();
keywords.add("123woods");
keywords.add("come");
keywords.add("you");
keywords.add("say");
By looking at it, the expected result would be 5 for "Say" + "come" + "you" + "say" + "123woods", counting "say" twice if we go lowercase. If we don't, then the count should be 4, "Say" being excluded and "say" included. Fine. My suggestion is:
// Set... ready...?
int counter = 0;
// Go!
for(String s : strings)
{
// Asking if the sentence exists in the keywords, not the other
// around, to find repeated keywords in the sentence.
Boolean found = keywords.contains(s.toLowerCase());
if(found)
{
counter ++;
System.out.println("Found: " + s);
}
}
// Statistics:
if (counter > 0)
{
System.out.println("In sentence: " + sentence + "\n"
+ "Count: " + counter);
}
And the results are:
Found: Say
Found: come
Found: you
Found: say
Found: 123woods
In sentence: Say that 123 of us will come by and meet you, say, at the woods of 123woods.
Count: 5

If you want to identify a whole word in a string and change the content of that word you can do this way. Your final string stays equals, except the word you treated. In this case "not" stays "'not'" in final string.
StringBuilder sb = new StringBuilder();
String[] splited = value.split("\\s+");
if(ArrayUtils.isNotEmpty(splited)) {
for(String valor : splited) {
sb.append(" ");
if("not".equals(valor.toLowerCase())) {
sb.append("'").append(valor).append("'");
} else {
sb.append(valor);
}
}
}
return sb.toString();

Java Split not working as expected

I am trying to use a simple split to break up the following string: 00-00000
My expression is: ^([0-9][0-9])(-)([0-9])([0-9])([0-9])([0-9])([0-9])
And my usage is:
String s = "00-00000";
String pattern = "^([0-9][0-9])(-)([0-9])([0-9])([0-9])([0-9])([0-9])";
String[] parts = s.split(pattern);
If I play around with the Pattern and Matcher classes I can see that my pattern does match and the matcher tells me my groupCount is 7 which is correct. But when I try and split them I have no luck.

String.split does not use capturing groups as its result. It finds whatever matches and uses that as the delimiter. So the resulting String[] are substrings in between what the regex matches. As it is the regex matches the whole string, and with the whole string as a delimiter there is nothing else left so it returns an empty array.
If you want to use regex capturing groups you will have to use Matcher.group(), String.split() will not do.

for your example, you could simply do this:
String s = "00-00000";
String pattern = "-";
String[] parts = s.split(pattern);

I can not be sure, but I think what you are trying to do is to get each matched group into an array.
Matcher matcher = Pattern.compile(pattern).matcher();
if (matcher.matches()) {
String s[] = new String[matcher.groupCount()) {
for (int i=0;i<matches.groupCount();i++) {
s[i] = matcher.group(i);
}
}
}

From the documentation:
String[] split(String regex) -- Returns: the array of strings computed by splitting this string around matches of the given regular expression
Essentially the regular expression is used to define delimiters in the input string. You can use capturing groups and backreferences in your pattern (e.g. for lookarounds), but ultimately what matters is what and where the pattern matches, because that defines what goes into the returned array.
If you want to split your original string into 7 parts using regular expression, then you can do something like this:
String s = "12-3456";
String[] parts = s.split("(?!^)");
System.out.println(parts.length); // prints "7"
for (String part : parts) {
System.out.println("Part [" + part + "]");
} // prints "[1] [2] [-] [3] [4] [5] [6] "
This splits on zero-length matching assertion (?!^), which is anywhere except before the first character in the string. This prevents the empty string to be the first element in the array, and trailing empty string is already discarded because we use the default limit parameter to split.
Using regular expression to get individual character of a string like this is an overkill, though. If you have only a few characters, then the most concise option is to use foreach on the toCharArray():
for (char ch : "12-3456".toCharArray()) {
System.out.print("[" + ch + "] ");
}
This is not the most efficient option if you have a longer string.
Splitting on -
This may also be what you're looking for:
String s = "12-3456";
String[] parts = s.split("-");
System.out.println(parts.length); // prints "2"
for (String part : parts) {
System.out.print("[" + part + "] ");
} // prints "[12] [3456] "