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Storing string into hashmap with occurrences

I have a method that returns some kind of string. I want to store the individual words in a HashMap with their number of occurrences?
public static void main(String[] args) {
String s = "{link:hagdjh, matrics:[{name:apple, value:1},{name:jeeva, value:2},{name:abc, value:0}]}";
String[] strs = s.split("matrics");
System.out.println("Substrings length:" + strs.length);
for (int i = 0; i < strs.length; i++) {
System.out.println(strs[i]);
}
}
For eg, I have a string- "{link:https://www.google.co.in/, matrics:[{name:apple, value:1},{name:graph, value:2},{name:abc, value:0}]}";
Now my hashmap should look like
apple = 1
graph = 2
abc = 0
How should I proceed?
I know how to use HashMaps. My problem, in this case, is that I don't know how to parse through the given string and store the words with their number of occurrences.

String regex = "\\{name:(.*), value:(\\d+)\\}";
HashMap<String, Integer> link = new HashMap<>();
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(s);
while (matcher.find()){
String found = matcher.group(1);
String number = matcher.group(2);
link.put(found, Integer.parseInt(number));
}

import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Main {
public static void main(String[] args) {
Map<String, Integer> map = new LinkedHashMap<String, Integer>();
Pattern pattern = Pattern.compile("matrics:\\[\\{(.*?)\\]\\}");
Matcher matcher = pattern
.matcher("{link:hagdjh, matrics:[{name:apple, value:1},{name:jeeva, value:2},{name:abc, value:0}]}");
String data = "";
if (matcher.find()) {
data = matcher.group();
}
List<String> records = new ArrayList<String>();
pattern = Pattern.compile("(?<=\\{).+?(?=\\})");
matcher = pattern.matcher(data);
while (matcher.find()) {
records.add(matcher.group());
}
for (String s : records) {
String[] parts = s.split(", ");
map.put(parts[0].substring(parts[0].indexOf(":") + 1),
Integer.parseInt(parts[1].substring(parts[1].indexOf(":") + 1)));
}
map.entrySet().forEach(entry -> {
System.out.println(entry.getKey() + " = " + entry.getValue());
});
}
}
Output:
apple = 1
jeeva = 2
abc = 0

It appeares that your data is in JSON format.
If it is guaranteed to be in JSON format, you can parse it using JSON parsing library and than analyze the matrics data in a convinient way (code follows).
If the data is not guaranteed to be in JSON format, you can use REGEX to help you parse it, as in Reza soumi's answer.
import org.json.JSONObject;
import org.json.JSONArray;
import java.util.HashMap;
String s = "{link:hagdjh, matrics:[{name:apple, value:1},{name:jeeva, value:2},{name:abc, value:0}]}";
JSONObject obj = new JSONObject(s);
JSONArray matrics = obj.getJSONArray("matrics");
System.out.println(matrics);
HashMap<String, Integer> matricsHashMap = new HashMap<String, Integer>();
for (int i=0;i < matrics.length();i++){
JSONObject matric = matrics.getJSONObject(i);
System.out.println("Adding matric: " + matric + " to hash map");
String matricName = matric.getString("name");
Integer matricValue = Integer.valueOf(matric.getInt("value"));
matricsHashMap.put(matricName, matricValue);
}
System.out.println(matricsHashMap);

Try this:
import static java.lang.System.err;
import static java.lang.System.out;
import static java.util.Arrays.stream;
import static java.util.stream.Collectors.groupingBy;
import static java.util.stream.Collectors.toMap;
/**
* Counting the words in a String.
*/
public class CountWordsInString
{
/*-----------*\
====** Constants **========================================================
\*-----------*/
/**
* An empty array of {#code ${type_name}} objects.
*/
public static final String INPUT = "{link:https://www.google.co.in/, matrics:[{name:apple, value:1},{name:graph, value:2},{name:abc, value:0}]}";
/*---------*\
====** Methods **==========================================================
\*---------*/
/**
* The program entry point.
*
* #param args The command line arguments.
*/
public static void main( final String... args )
{
try
{
final var result = stream( INPUT.split( "\\W+" ) )
.filter( s -> !s.isBlank() )
.filter( s -> !s.matches( "\\d*" ) )
.collect( groupingBy( s -> s ) )
.entrySet()
.stream()
.collect( toMap( k -> k.getKey(), v -> Long.valueOf( v.getValue().size() ) ) );
out.println( result.getClass() );
for( final var entry : result.entrySet() )
{
out.printf( "'%s' occurred %d times%n", entry.getKey(), entry.getValue() );
}
}
catch( final Throwable t )
{
//---* Handle any previously unhandled exceptions *----------------
t.printStackTrace( err );
}
} // main()
}
// class CountWordsInString
Confessed, not the most obvious solution, but I wanted to have some fun with it, too.
The INPUT.split( "\\W+" ) gives you the words in the string, but also numbers and an 'empty' word at the beginning.
The 'empty' word is eliminated with the first filter() statement, the numbers go with the second.
The first collect( groupingBy() ) gives you a HashMap<String,List<String>>, so I had to convert that to a HashMap<String,Long> in the following steps (basically with the second collect( groupingBy() )).
May be there is a more efficient solution, or one that is more elegant, or even one that is both, more efficient and more elegant … but it works as expected, and I had some fun with it.
The output is:
class java.util.HashMap
'apple' occurred 1 times
'matrics' occurred 1 times
'abc' occurred 1 times
'in' occurred 1 times
'www' occurred 1 times
'name' occurred 3 times
'link' occurred 1 times
'google' occurred 1 times
'https' occurred 1 times
'co' occurred 1 times
'value' occurred 3 times
'graph' occurred 1 times

Why does Player name get printed twice by my code?

Main Class
package main;
import static org.junit.Assert.*;
import java.util.ArrayList;
import org.junit.Test;
import lib.Die;
import lib.Name;
import lib.PairOfDice;
import lib.Player;
public class PlayerAppTest {
/* Please note - when we come to mark the solution to this unit test we will change the input
* data set for the players added to the list to ensure the solution works dynamically based
* upon any given data set and is not hardcoded in any way.
*/
#Test
public void testExecute() {
ArrayList<Player> players = new ArrayList<>();
players.add(new Player(new Name("Joe", "Bloggs"), new PairOfDice()));
players.add(new Player(new Name("Fred", "Jones"), new Die()));
players.add(new Player(new Name("Nila", "Singh"), new PairOfDice(new Die(5), new Die(5))));
String result = PlayerApp.execute(players, "Cassie Downturn");
String expectedResult = "cassie, DOWNTURN\nnila, SINGH\n";
assertEquals("The string returned should match the expected result (run 1)", expectedResult, result);
/* Test with a second set of input data */
ArrayList<Player> players2 = new ArrayList<>();
players2.add(new Player(new Name("David", "Blunt"), new PairOfDice()));
players2.add(new Player(new Name("Tim", "Jonas"), new Die(5)));
players2.add(new Player(new Name("Remi", "Patel"), new Die()));
String result2 = PlayerApp.execute(players2, "Cassie Downturn");
String expectedResult2 = "cassie, DOWNTURN\ntim, JONAS\nremi, PATEL\n";
assertEquals("The string returned should match the expected result (run 2)", expectedResult2, result2);
}
}
Hello, this is the JUnit test which I have to pass, below is the code that I have written in my main package;
JUnit Test Class
package main;
import java.util.ArrayList;
import lib.Player;
public class PlayerApp {
public static String execute(ArrayList<Player> players, String fullName) {
players.get(0).setFullPlayerName(fullName);
fullName = "";
for (int i = 0; i <players.size(); i ++) {
if (players.get(i).getName().getFirstName().toLowerCase().contains("a") || players.get(i).getName().getFamilyName().toUpperCase().contains("a")) {
fullName = players.get(i).getName().getFirstName().toLowerCase() + ", " + players.get(i).getName().getFamilyName().toUpperCase() + "\n";
}
System.out.println(fullName);
}
return fullName;
}
}
This is the code in my main package, I am trying to print out the names which contain a char "a" in the first name, the first name should be lowercase and the family name should be uppercase. It should print out
cassie, DOWNTURN
nila, SINGH which is the names with a new line between them, however, when i print it, it prints the following;
cassie, DOWNTURN
cassie, DOWNTURN
nila, SINGH
I am confused as to why cassie, DOWNTURN has been printed twice as i cannot find the error in my code, any help would be greatly appreciated, thank you.

You will print it even if the if doesn't match as it's outside the if-statement. Move it inside instead.
for (int i = 0; i <players.size(); i ++) {
if (players.get(i).getName().getFirstName().toLowerCase().contains("a") || players.get(i).getName().getFamilyName().toUpperCase().contains("a")) {
fullName = players.get(i).getName().getFirstName().toLowerCase() + ", " + players.get(i).getName().getFamilyName().toUpperCase() + "\n";
System.out.println(fullName);
}
}

Your print statement is not conditional and will always execute, move it inside the if. You're printing twice as your are not changing the value in fullName if the if condition does not evaluate as true. Further your family name comparison will always be false as you're comparing upper and lower case.
Your code can also be tided up and made easier to read:
for(Player player : players){
if(player.getName().getFirstName()).toLowerCase().contains("a")||player.getName().getFamilyName().toUpperCase.contains("A"))){
String fullName = players.get(i).getName().getFirstName().toLowerCase() + ", " + players.get(i).getName().getFamilyName().toUpperCase() + "\n";
System.out.println(fullname);
}
}

How do I parse a text file to write certain lines in another text file using java?

I am learning how to work with files in Java. I have a sample file which contains key pairs and it values. I am trying to find a key pairs and if it matches, then output file would be updated with both, key pair and it's value. I am able to get key pairs in output file but unable to get values too. Stringbuilder may work here to append strings but I don't know how.
Below are my input and output files.
Input File:
born time 9 AM London -- kingNumber 1234567890 -- address: abc/cd/ef -- birthmonth: unknown
born time 9 AM Europe -- kingNumber 1234567890 -- address: abc/cd/ef -- birthmonth: december
Expected Output File:
kingNumber 1234567890 birthmonth unknown
kingNumber 1234567890 birthmonth unkbown
Current Output File:
kingNumber birthmonth
kingNumber birthmonth
I am able to write key pair ("kingNumber" and "birthmonth" in this case) to output file but I am not sure what I can do to get it's value too.
String kn = "kingNumber:";
String bd = "birthmonth:";
try {
File f = new File("sample.txt");
Scanner sc = new Scanner(f);
FileWriter fw = new FileWriter("output.txt");
while(sc.hasNextLine()) {
String lineContains = sc.next();
if(lineContains.contains(kn)) {
fw.write(kn + "\n");
// This is where I am stuck. What
// can I do to get it's value (number in this case).
}
else if(lineContains.contains(bd)) {
fw.write(bd);
// This is where I am stuck. What
// can I do to get it's value (birthday in this case).
}
}
} catch (IOException e) {
e.printStackTrace();
}

you could use java.util.regex.Pattern & java.util.regex.Matcherwith a pattern alike:
^born\stime\s([a-zA-Z0-9\s]*)\s--\skingNumber\s(\d+)\s--\saddress:\s([a-zA-Z0-9\s/]*)\s--\sbirthmonth:\s([a-zA-Z0-9\s]*)$
write less, do more.

I have written a simple parser that it following data format from your example.
You will need to call it like this:
PairParser parser = new PairParser(lineContains);
then you can get value from the parser by pair keys
How to get value:
parser.getValue("kingNumber")
Note that keys do not have trailing column character.
The parser code is here:
package com.grenader.example;
import java.util.HashMap;
import java.util.Map;
public class PairParser {
private Map<String, String> data = new HashMap<>();
/**
* Constructor, prepare the data
* #param dataString line from the given data file
*/
public PairParser(String dataString) {
if (dataString == null || dataString.isEmpty())
throw new IllegalArgumentException("Data line cannot be empty");
// Spit the input line into array of string blocks based on '--' as a separator
String[] blocks = dataString.split("--");
for (String block : blocks)
{
if (block.startsWith("born time")) // skip this one because it doesn't looks like a key/value pair
continue;
String[] strings = block.split("\\s");
if (strings.length != 3) // has not exactly 3 items (first items is empty), skipping this one as well
continue;
String key = strings[1];
String value = strings[2];
if (key.endsWith(":"))
key = key.substring(0, key.length()-1).trim();
data.put(key.trim(), value.trim());
}
}
/**
* Return value based on key
* #param key
* #return
*/
public String getValue(String key)
{
return data.get(key);
}
/**
* Return number of key/value pairs
* #return
*/
public int size()
{
return data.size();
}
}
And here is the Unit Test to make sure that the code works
package com.grenader.example;
import com.grenader.example.PairParser;
import org.junit.Test;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.fail;
public class PairParserTest {
#Test
public void getValue_Ok() {
PairParser parser = new PairParser("born time 9 AM London -- kingNumber 1234567890 -- address: abc/cd/ef -- birthmonth: unknown");
assertEquals("1234567890", parser.getValue("kingNumber"));
assertEquals("unknown", parser.getValue("birthmonth"));
}
#Test(expected = IllegalArgumentException.class)
public void getValue_Null() {
new PairParser(null);
fail("This test should fail with Exception");
}
#Test(expected = IllegalArgumentException.class)
public void getValue_EmptyLine() {
new PairParser("");
fail("This test should fail with Exception");
}
#Test()
public void getValue_BadData() {
PairParser parser = new PairParser("bad data bad data");
assertEquals(0, parser.size());
}
}

Fetch all the hyperlinks from a webpage and recursively doing that in java

1 .Fetch all contents from a Webpage
2. fetch hyperlinks from the webpage.
3. Repeat the 1 & 2 from the fetched hyperlink
4. repeat the process untill 200 hyperlinks regietered or no more hyperlink to fetch.
I wrote a sample programs but due to poor understanding of recursion , my loop became an infinite loop.
Suggest me to solve the code matching the expectation.
import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Content
{
private static final String HTML_A_HREF_TAG_PATTERN =
"\\s*(?i)href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">\\s]+))";
Pattern pattern;
public Content ()
{
pattern = Pattern.compile(HTML_A_HREF_TAG_PATTERN);
}
private void fetchContentFromURL(String strLink) {
String content = null;
URLConnection connection = null;
try {
connection = new URL(strLink).openConnection();
Scanner scanner = new Scanner(connection.getInputStream());
scanner.useDelimiter("\\Z");
content = scanner.next();
}catch ( Exception ex ) {
ex.printStackTrace();
return;
}
fetchURL(content);
}
private void fetchURL ( String content )
{
Matcher matcher = pattern.matcher( content );
while(matcher.find()) {
String group = matcher.group();
if(group.toLowerCase().contains( "http" ) || group.toLowerCase().contains( "https" )) {
group = group.substring( group.indexOf( "=" )+1 );
group = group.replaceAll( "'", "" );
group = group.replaceAll( "\"", "" );
System.out.println("lINK "+group);
fetchContentFromURL(group);
}
}
System.out.println("DONE");
}
/**
* #param args
*/
public static void main ( String[] args )
{
new Content().fetchContentFromURL( "http://www.google.co.in" );
}
}
I am open for any other solution as well but want to stick with core java Api only no 3rd party.

One possible option here is to remember all visited links to avoid cyclic paths. Here's how to archive it with additional Set storage for already visited links:
public class Content {
private static final String HTML_A_HREF_TAG_PATTERN =
"\\s*(?i)href\\s*=\\s*(\"([^\"]*\")|'[^']*'|([^'\">\\s]+))";
private Pattern pattern;
private Set<String> visitedUrls = new HashSet<String>();
public Content() {
pattern = Pattern.compile(HTML_A_HREF_TAG_PATTERN);
}
private void fetchContentFromURL(String strLink) {
String content = null;
URLConnection connection = null;
try {
connection = new URL(strLink).openConnection();
Scanner scanner = new Scanner(connection.getInputStream());
scanner.useDelimiter("\\Z");
if (scanner.hasNext()) {
content = scanner.next();
visitedUrls.add(strLink);
fetchURL(content);
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
private void fetchURL(String content) {
Matcher matcher = pattern.matcher(content);
while (matcher.find()) {
String group = matcher.group();
if (group.toLowerCase().contains("http") || group.toLowerCase().contains("https")) {
group = group.substring(group.indexOf("=") + 1);
group = group.replaceAll("'", "");
group = group.replaceAll("\"", "");
System.out.println("lINK " + group);
if (!visitedUrls.contains(group) && visitedUrls.size() < 200) {
fetchContentFromURL(group);
}
}
}
System.out.println("DONE");
}
/**
* #param args
*/
public static void main(String[] args) {
new Content().fetchContentFromURL("http://www.google.co.in");
}
}
I also fixed some other issues in fetching logic, now it works as expected.

inside the fetchContentFromURL method you should record which url u r currently fetching, and if that url has already be fetched then skip it. otherwise two page A, B, which has a link point to each other will cause your code keep fetching.

In addition to JK1's answer, for achieving target 4 of your question, you might want to maintain the count of hyperlinks as instance variable. A rough pseudo code might be(you can adjust the exact count. Also as an alternate, you can use HashSet length to know the number of Hyperlinks your program has parsed till now):
if (!visitedUrls.contains(group) && noOfHyperlinksVisited++ < 200) {
fetchContentFromURL(group);
}
However, I was not sure whether you want a total of 200 hyperlinks OR want to traverse to a depth of 200 links from starting page. In case it is later, you might wish to explore Breadth First Search, which will let you know when you have reached your target depth.

How to get the phone number from a vcard

I am using cardme library to deal with vcards. Following is my code
package vcardtest;
import java.io.*;
import java.util.Iterator;
import java.util.logging.Level;
import java.util.logging.Logger;
import net.sourceforge.cardme.engine.VCardEngine;
import net.sourceforge.cardme.vcard.VCard;
import net.sourceforge.cardme.vcard.features.EmailFeature;
import net.sourceforge.cardme.vcard.features.NameFeature;
import net.sourceforge.cardme.vcard.features.NicknameFeature;
import net.sourceforge.cardme.vcard.features.TelephoneFeature;
import net.sourceforge.cardme.vcard.types.parameters.TelephoneParameterType;
public class VCardTest
{
public static void main(String[] args)
{
File vcardFile = new File("C:/Users/yohan/Contacts/Yohan Weerasinghe.vcf");
VCardEngine vcardEngine = new VCardEngine();
try
{
VCard vcard = vcardEngine.parse(vcardFile);
String name = vcard.getName().getGivenName();
EmailFeature email = vcard.getEmails().next();
String sEmail = email.getEmail();
NicknameFeature nickName = vcard.getNicknames();
Iterator<String> nicknames = nickName.getNicknames();
String sNickName = nicknames.next();
Iterator<TelephoneFeature> telephoneNumbers = vcard.getTelephoneNumbers();
TelephoneFeature next = telephoneNumbers.next();
String telephone = "";
while(vcard.getTelephoneNumbers().hasNext())
{
TelephoneFeature next1 = vcard.getTelephoneNumbers().next();
telephone = next1.getTelephone();
System.out.println(telephone);
}
Iterator<TelephoneParameterType> telephoneParameterTypes = next.getTelephoneParameterTypes();
TelephoneParameterType next1 = telephoneParameterTypes.next();
String type = next1.getType();
TelephoneParameterType next2 = telephoneParameterTypes.next();
String type2 = next2.getType();
System.out.println( name );
System.out.println(sEmail);
System.out.println(sNickName);
System.out.println(type);
System.out.println(type2);
} catch (IOException ex)
{
ex.printStackTrace();
}
}
}
However, there is no method called getNumber() or something. How can I get the mobile numbers and land numbers? Please help!
NOTE: I UPDATED THE CODE. In there, you can see I managed to get the phone number. But, this returns only the HOME phone and not anything else. Even the loop is not stopping. Please help!

I can see
TelephoneFeature.getTelephone()
I'd also suggest taking a look at
TelephoneFeature.getTelephoneParameterTypes()
to see the types
UPDATE
Be careful with the iterators
Each call to vcard.getTelephoneNumbers() is creating a new Iterator, which means you could end up in an infinite loop.
Iterator<TelephoneFeature> itNumbers = vcard.getTelephoneNumbers();
while (itNumbers.hasNext()) {
TelephoneFeature next1 = itNumbers.next();
String telephone = next1.getTelephone();
System.out.println(telephone);
System.out.println("types = " + next1.getExtendedTelephoneParameterSize());
Iterator<XTelephoneParameterType> itTypes = next1.getExtendedTelephoneParameterTypes();
while (itTypes.hasNext()) {
XTelephoneParameterType next = itTypes.next();
System.out.println(" - " + next.getType() + " / " + next.getDescription());
}
}
I stand corrected, the problem (isn't a bug) it's with the tester, not the API :P
If you add
Iterator<TelephoneParameterType> itNTypes = next1.getTelephoneParameterTypes();
while (itNTypes .hasNext()) {
TelephoneParameterType next = itNTypes .next();
System.out.println(" - " + next.getType() + " / " + next.getDescription());
}
to the previous loop, you should get what you're looking for