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Can not count how many number of unique date are available in every part of string

I divided my string in three part using newline ('\n'). The output that i want to achieve: count how many number of unique date are available in every part of string.
According to below code, first part contains two unique date, second part contains two and third part contains three unique date. So the output should be like this: 2,2,3,
But after run this below code i get this Output: 5,5,5,5,1,3,1,
How do i get Output: 2,2,3,
Thanks in advance.
String strH;
String strT = null;
StringBuilder sbE = new StringBuilder();
String strA = "2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-11,2021-03-11,2021-03-11,2021-03-11,2021-03-11," + '\n' +
"2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-15,2021-03-15,2021-03-15,2021-03-15,2021-03-15," + '\n' +
"2021-03-02,2021-03-09,2021-03-07,2021-03-09,2021-03-09,";
String[] strG = strA.split("\n");
for(int h=0; h<strG.length; h++){
strH = strG[h];
String[] words=strH.split(",");
int wrc=1;
for(int i=0;i<words.length;i++) {
for(int j=i+1;j<words.length;j++) {
if(words[i].equals(words[j])) {
wrc=wrc+1;
words[j]="0";
}
}
if(words[i]!="0"){
sbE.append(wrc).append(",");
strT = String.valueOf(sbE);
}
wrc=1;
}
}
Log.d("TAG", "Output: "+strT);

I would use a set here to count the duplicates:
String strA = "2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-11,2021-03-11,2021-03-11,2021-03-11,2021-03-11" + "\n" +
"2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-15,2021-03-15,2021-03-15,2021-03-15,2021-03-15" + "\n" +
"2021-03-02,2021-03-09,2021-03-07,2021-03-09,2021-03-09";
String[] lines = strA.split("\n");
List<Integer> counts = new ArrayList<>();
for (String line : lines) {
counts.add(new HashSet<String>(Arrays.asList(line.split(","))).size());
}
System.out.println(counts); // [2, 2, 3]
Note that I have done a minor cleanup of the strA input by removing the trailing comma from each line.

With Java 8 Streams, this can be done in a single statement:
String strA = "2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-02,2021-03-11,2021-03-11,2021-03-11,2021-03-11,2021-03-11," + '\n' +
"2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-07,2021-03-15,2021-03-15,2021-03-15,2021-03-15,2021-03-15," + '\n' +
"2021-03-02,2021-03-09,2021-03-07,2021-03-09,2021-03-09,";
String strT = Pattern.compile("\n").splitAsStream(strA)
.map(strG -> String.valueOf(Pattern.compile(",").splitAsStream(strG).distinct().count()))
.collect(Collectors.joining(","));
System.out.println(strT); // 2,2,3
Note that Pattern.compile("\n").splitAsStream(strA) can also be written as Arrays.stream(strA.split("\n")), which is shorter to write, but creates an unnecessary intermediate array. Matter of personal preference which is better.
String strT = Arrays.stream(strA.split("\n"))
.map(strG -> String.valueOf(Arrays.stream(strG.split(",")).distinct().count()))
.collect(Collectors.joining(","));
The first version can be further micro-optimized by only compiling the regex once:
Pattern patternComma = Pattern.compile(",");
String strT = Pattern.compile("\n").splitAsStream(strA)
.map(strG -> String.valueOf(patternComma.splitAsStream(strG).distinct().count()))
.collect(Collectors.joining(","));

How to pattern match and transform string to generate certain output?

The below code is for getting some form of input which includes lots of whitespace in between important strings and before and after the important strings, so far I have been able to filter the whitespace out. After preparing the string what I want to do is process it.
Here is an example of the inputs that I may get and the favorable output I want;
Input
+--------------+
EDIT example.mv Starter web-onyx-01.example.net.mv
Notice how whitespace id before and after the domain, this whitespace could be concluded as random amount.
Output
+--------------+
example.mv. in ns web-onyx-01.example.net.mv.
In the output the important bit is the whitespace between the domain (Example.) and the keyword (in) and keyword (ns) and host (web-onyx-01.example.net.mv.)
Also notice the period (".") after the domain and host. Another part is the fact that if its a (.mv) ccTLD we will have to remove that bit from the string,
What I would like to achieve is this transformation with multiple lines of text, meaning I want to process a bunch of unordered chaotic list of strings and batch process them to produce the clean looking outputs.
The code is by no-means any good design, but this is at least what I have come up with. NOTE: I am a beginner who is still learning about programming. I would like your suggestions to improve the code as well as to solve the problem at hand i.e transform the input to the desired output.
P.S The output is for zone files in DNS, so errors can be very problematic.
So far my code is accepting text from a textarea and outputs the text into another textarea which shows the output.
My code works for as long as the array length is 2 and 3 but fails at anything larger. So how do I go about being able to process the input to the output dynamically for as big as the list/array may become in the future?
String s = jTextArea1.getText();
Pattern p = Pattern.compile("ADD|EDIT|DELETE|Domain|Starter|Silver|Gold|ADSL Business|Pro|Lite|Standard|ADSL Multi|Pro Plus", Pattern.MULTILINE);
Matcher m = p.matcher(s);
s = m.replaceAll("");
String ms = s.replaceAll("(?m)(^\\s+|[\\t\\f ](?=[\\t\\f ])|[\\t\\f ]$|\\s+\\z)", "");
String[] last = ms.split(" ");
for (String test : last){
System.out.println(test);
}
System.out.println("The length of array is: " +last.length);
if (str.isContain(last[0], ".mv")) {
if (last.length == 2) {
for(int i = 0; i < last.length; i++) {
last[0] = last[0].replaceFirst(".mv", "");
System.out.println(last[0]);
last[i] += ".";
if (last[i] == null ? last[0] == null : last[i].equals(last[0])) {
last[i]+= " in ns ";
}
String str1 = String.join("", last);
jTextArea2.setText(str1);
System.out.println(str1);
}
}
else if (last.length == 3) {
for(int i = 0; i < last.length; i++) {
last[0] = last[0].replaceFirst(".mv", "");
System.out.println(last[0]);
last[i] += ".";
if (last[i] == null ? last[0] == null : last[i].equals(last[0])) {
last[i]+= " in ns ";
}
if (last[i] == null ? last[1] == null : last[i].equals(last[1])){
last[i] += "\n";
}
if (last[i] == null ? last[2] == null : last[i].equals(last[2])){
last[i] = last[0] + last[2];
}
String str1 = String.join("", last);
jTextArea2.setText(str1);
System.out.println(str1);
}
}
}

As I understand your question you have multiple lines of input in the following form:
whitespace[command]whitespace[domain]whitespace[label]whitespace[target-domain]whitespace
You want to convert that to the following form such that multiple lines are aligned nicely:
[domain]. in ns [target-domain].
To do that I'd suggest the following:
Split your input into multiple lines
Use a regular expression to check the line format (e.g. for a valid command etc.) and extract the domains
store the maximum length of both domains separately
build a string format using the maximum lengths
iterate over the extraced domains and build a string for that line using the format defined in step 4
Example:
String input = " EDIT domain1.mv Starter example.domain1.net.mv \n" +
" DELETE long-domain1.mv Silver long-example.long-domain1.net.mv \n" +
" ADD short-domain1.mv ADSL Business ex.sdomain1.net.mv \n";
//step 1: split the input into lines
String[] lines = input.split( "\n" );
//step 2: build a regular expression to check the line format and extract the domains - which are the (\S+) parts
Pattern pattern = Pattern.compile( "^\\s*(?:ADD|EDIT|DELETE)\\s+(\\S+)\\s+(?:Domain|Starter|Silver|Gold|ADSL Business|Pro|Lite|Standard|ADSL Multi|Pro Plus)\\s+(\\S+)\\s*$" );
List<String[]> lineList = new LinkedList<>();
int maxLengthDomain = 0;
int maxLengthTargetDomain = 0;
for( String line : lines )
{
//step 2: check the line
Matcher matcher = pattern.matcher( line );
if( matcher.matches() ) {
//step 2: extract the domains
String domain = matcher.group( 1 );
String targetDomain = matcher.group( 2 );
//step 3: get the maximum length of the domains
maxLengthDomain = Math.max( maxLengthDomain, domain.length() );
maxLengthTargetDomain = Math.max( maxLengthTargetDomain, targetDomain.length() );
lineList.add( new String[] { domain, targetDomain } );
}
}
//step 4: build the format string with variable lengths
String formatString = String.format( "%%-%ds in ns %%-%ds", maxLengthDomain + 5, maxLengthTargetDomain + 2 );
//step 5: build the output
for( String[] line : lineList ) {
System.out.println( String.format( formatString, line[0] + ".", line[1] + "." ) );
}
Result:
domain1.mv. in ns example.domain1.net.mv.
long-domain1.mv. in ns long-example.long-domain1.net.mv.
short-domain1.mv. in ns ex.sdomain1.net.mv.

JDBCTemplate queryForMap compare and replace value in extracted lines

Can you help me to understand why my code doesn't work, please?
I am trying to get values from 2 columns from my database and store them in a hashmap where K_PARAM is my key and L_PARAM is my value. Then I would like to compare 2 characters from a line that I am extracting and see if these 2 characters are equals to my key or not. In case they are equals, I replace key with value.
Thanks in advance. This is the code :
if (action.equals("RP")) {
if (marqueCarte = null) {
jdbcTemplate.query(" select K_PARAM, L_PARAM from DLCOA.DLC_ADM_PARAMS where K_CHX_PARAM = '50'", new ResultSetExtractor<Map>(){
#Override
public Map extractData(ResultSet rs) throws SQLException,DataAccessException {
 HashMap<String,String> marqueCarte = new HashMap<String,String>();
while (rs.next()) {
marqueCarte.put(rs.getString("K_PARAM"),rs.getString("L_PARAM"));
if (line.contains("blocE")) {
if (line.substring(line.indexOf("blocE") + 15, line.indexOf("blocE") + 15 + (line.substring(line.indexOf("blocE")+15)).indexOf("#")).equals(rs.getString("K_PARAM"))){
line = line.replace(line.substring(line.indexOf("blocE") + 15, line.indexOf("blocE") + 15 + (line.substring(line.indexOf("blocE")+15)).indexOf("#")),rs.getString("L_PARAM") );
}
}
   }
return marqueCarte;
}
}
}
}

I got a more readable and modifiable solution for your second problem.
(I'm still not sure what's your first one)
Using regex and patterns you can achieve the replacement you want.
Let's assume that you are searching for the text "blocE" followed by 15 characters, followed at the same time by the text contained in rs.getString("K_PARAM") plus an "#"
We can model what you search as a pattern like this
"(blocE)(.{15})(" + key + "#)"
Parenthesis allow us to establish different groups in the regex.
Group 1 - blocE
Group 2 - 15 characters
Group 3 - key + #
Being group 0 the complete matching expression.
Knowing this you can do the replacement applying the following code
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class TestRegex {
public static void main(String[] args) {
String key = "KEY"; // rs.getString("K_PARAM")
String value = "VALUE"; // rs.getString("L_PARAM")
Pattern pattern = Pattern.compile("(blocE)(.{15})(" + key + "#)");
String input ="helloworldblocE111111111111111KEY#blocE111111111111111KEY";
Matcher m = pattern.matcher(input);
if (m.find()) {
String text2replace = m.group(0);
String replacement = m.group(1) + m.group(2) + value;
System.out.println(input.replaceFirst(text2replace, replacement));
}
}
}
If your pattern changes, you only have to change one line and you do not have to worry about such quantity of indexOf.

Having an issue with formatting a String input

I'm trying to get the input that the user enters to go to lower-case and then put the first character in the input to upper-case. For example, If I enter aRseNAL for my first input, I want to format the input so that it will put "Arsenal" into the data.txt file, I'm also wondering if there's a way to put each first character to upper-case if there's more than one word for a team ie. mAN uNiTeD formatted to Man United to be written to the file.
The code I have below is what i tried and I cannot get it to work. Any advice or help would be appreciated.
import java.io.*;
import javax.swing.*;
public class write
{
public static void main(String[] args) throws IOException
{
FileWriter aFileWriter = new FileWriter("data.txt");
PrintWriter out = new PrintWriter(aFileWriter);
String team = "";
for(int i = 1; i <= 5; i++)
{
boolean isTeam = true;
while(isTeam)
{
team = JOptionPane.showInputDialog(null, "Enter a team: ");
if(team == null || team.equals(""))
JOptionPane.showMessageDialog(null, "Please enter a team.");
else
isTeam = false;
}
team.toLowerCase(); //Put everything to lower-case.
team.substring(0,1).toUpperCase(); //Put the first character to upper-case.
out.println(i + "," + team);
}
out.close();
aFileWriter.close();
}
}

In Java, strings are immutable (cannot be changed) so methods like substring and toLowerCase generate new strings - they don't modify your existing string.
So rather than:
team.toLowerCase();
team.substring(0,1).toUpperCase();
out.println(team);
You'd need something like:
String first = team.substring(0,1).toUpperCase();
String rest = team.substring(1,team.length()).toLowerCase();
out.println(first + rest);

Similar as #DNA suggested but that will throw Exception if String length is 1. So added a check for same.
String output = team.substring(0,1).toUpperCase();
// if team length is >1 then only put 2nd part
if (team.length()>1) {
output = output+ team.substring(1,team.length()).toLowerCase();
}
out.println(i + "," + output);

Trim() in Java not working the way I expect? [duplicate]

This question already has answers here:
Closed 10 years ago.
Possible Duplicate:
Query about the trim() method in Java
I am parsing a site's usernames and other information, and each one has a bunch of spaces after it (but spaces in between the words).
For example: "Bob the Builder " or "Sam the welder ". The numbers of spaces vary from name to name. I figured I'd just use .trim(), since I've used this before.
However, it's giving me trouble. My code looks like this:
for (int i = 0; i < splitSource3.size(); i++) {
splitSource3.set(i, splitSource3.get(i).trim());
}
The result is just the same; no spaces are removed at the end.
Thank you in advance for your excellent answers!
UPDATE:
The full code is a bit more complicated, since there are HTML tags that are parsed out first. It goes exactly like this:
for (String s : splitSource2) {
if (s.length() > "<td class=\"dddefault\">".length() && s.substring(0, "<td class=\"dddefault\">".length()).equals("<td class=\"dddefault\">")) {
splitSource3.add(s.substring("<td class=\"dddefault\">".length()));
}
}
System.out.println("\n");
for (int i = 0; i < splitSource3.size(); i++) {
splitSource3.set(i, splitSource3.get(i).substring(0, splitSource3.get(i).length() - 5));
splitSource3.set(i, splitSource3.get(i).trim());
System.out.println(i + ": " + splitSource3.get(i));
}
}
UPDATE:
Calm down. I never said the fault lay with Java, and I never said it was a bug or broken or anything. I simply said I was having trouble with it and posted my code for you to collaborate on and help solve my issue. Note the phrase "my issue" and not "java's issue". I have actually had the code printing out
System.out.println(i + ": " + splitSource3.get(i) + "*");
in a for each loop afterward.
This is how I knew I had a problem.
By the way, the problem has still not been fixed.
UPDATE:
Sample output (minus single quotes):
'0: Olin D. Kirkland                                          '
'1: Sophomore                                          '
'2: Someplace, Virginia  12345<br />VA SomeCity<br />'
'3: Undergraduate                                          '
EDIT the OP rephrased his question at Query about the trim() method in Java, where the issue was found to be Unicode whitespace characters which are not matched by String.trim().

It just occurred to me that I used to have this sort of issue when I worked on a screen-scraping project. The key is that sometimes the downloaded HTML sources contain non-printable characters which are non-whitespace characters too. These are very difficult to copy-paste to a browser. I assume that this could happened to you.
If my assumption is correct then you've got two choices:
Use a binary reader and figure out what those characters are - and delete them with String.replace(); E.g.:
private static void cutCharacters(String fromHtml) {
String result = fromHtml;
char[] problematicCharacters = {'\000', '\001', '\003'}; //this could be a private static final constant too
for (char ch : problematicCharacters) {
result = result.replace(ch, ""); //I know, it's dirty to modify an input parameter. But it will do as an example
}
return result;
}
If you find some sort of reoccurring pattern in the HTML to be parsed then you can use regexes and substrings to cut the unwanted parts. E.g.:
private String getImportantParts(String fromHtml) {
Pattern p = Pattern.compile("(\\w*\\s*)"); //this could be a private static final constant as well.
Matcher m = p.matcher(fromHtml);
StringBuilder buff = new StringBuilder();
while (m.find()) {
buff.append(m.group(1));
}
return buff.toString().trim();
}

Works without a problem for me.
Here your code a bit refactored and (maybe) better readable:
final String openingTag = "<td class=\"dddefault\">";
final String closingTag = "</td>";
List<String> splitSource2 = new ArrayList<String>();
splitSource2.add(openingTag + "Bob the Builder " + closingTag);
splitSource2.add(openingTag + "Sam the welder " + closingTag);
for (String string : splitSource2) {
System.out.println("|" + string + "|");
}
List<String> splitSource3 = new ArrayList<String>();
for (String s : splitSource2) {
if (s.length() > openingTag.length() && s.startsWith(openingTag)) {
String nameWithoutOpeningTag = s.substring(openingTag.length());
splitSource3.add(nameWithoutOpeningTag);
}
}
System.out.println("\n");
for (int i = 0; i < splitSource3.size(); i++) {
String name = splitSource3.get(i);
int closingTagBegin = splitSource3.get(i).length() - closingTag.length();
String nameWithoutClosingTag = name.substring(0, closingTagBegin);
String nameTrimmed = nameWithoutClosingTag.trim();
splitSource3.set(i, nameTrimmed);
System.out.println("|" + splitSource3.get(i) + "|");
}
I know that's not a real answer, but i cannot post comments and this code as a comment wouldn't fit, so I made it an answer, so that Olin Kirkland can check his code.