I really don't like this HW

src/main/java/cz/muni/fi/pb162/hw03/csv/impl/CsvToolkit.java

 package cz.muni.fi.pb162.hw03.csv.impl;
 
 import cz.muni.fi.pb162.hw03.csv.CsvParser;
+import cz.muni.fi.pb162.hw03.csv.CsvReader;
 
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
 import java.nio.charset.Charset;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.Map;
+
+import static cz.muni.fi.pb162.hw03.csv.CsvParser.DEFAULT_CHARSET;
+import static cz.muni.fi.pb162.hw03.csv.CsvParser.DEFAULT_DELIMITER;
 
 /**
  * Factory class for CSV processing
  */
-public final class CsvToolkit {
+public final class CsvToolkit{
 
     private CsvToolkit() {
         // intentionally private to prevent instantiation
     }
-
     /**
      * Creates instance of {@link CsvParser} with default delimiter and charset
      *
      * @return parser
      */
     public static CsvParser parser() {
-        throw new UnsupportedOperationException("Implement this method!");
+
+        return parser(DEFAULT_DELIMITER, DEFAULT_CHARSET);
     }
 
     /**
@@ -30,6 +45,7 @@ public final class CsvToolkit {
      * @return parser
      */
     public static CsvParser parser(String delimiter, Charset charset) {
-        throw new UnsupportedOperationException("Implement this method!");
+        return new Parser(delimiter, charset);
     }
+
 }

src/main/java/cz/muni/fi/pb162/hw03/csv/impl/Parser.java

+package cz.muni.fi.pb162.hw03.csv.impl;
+
+import cz.muni.fi.pb162.hw03.csv.CsvParser;
+import cz.muni.fi.pb162.hw03.csv.CsvReader;
+
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.FileReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.Charset;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Map;
+import java.util.stream.Collectors;
+
+public class Parser implements CsvParser {
+    private final String delimiter;
+    private final Charset charset;
+
+    public Parser(String delimiter, Charset charset) {
+        this.delimiter = delimiter;
+        this.charset = charset;
+    }
+
+    @Override
+    public CsvReader<List<String>> open(Path path) throws IOException {
+        return open(new FileInputStream(path.toString()));
+    }
+
+    @Override
+    public CsvReader<List<String>> open(InputStream is) throws IOException {
+        return new Reader(is,charset,delimiter);
+    }
+
+    @Override
+    public CsvReader<Map<String, String>> openWithHeader(Path path) throws IOException {
+        return openWithHeader(new FileInputStream(path.toString()));
+    }
+
+    @Override
+    public CsvReader<Map<String, String>> openWithHeader(InputStream is) throws IOException {
+        return new ReaderWithHeader(is,charset, delimiter);
+    }
+
+    @Override
+    public List<List<String>> readAll(Path path) throws IOException {
+        List res = new ArrayList();
+        open(path).forEach(x -> res.add(x));
+        return res;
+    }
+
+    @Override
+    public List<Map<String, String>> readAllWithHeader(Path path) throws IOException {
+        List res = new ArrayList();
+        openWithHeader(path).forEach(x -> res.add(x));
+        return res;
+    }
+}

src/main/java/cz/muni/fi/pb162/hw03/csv/impl/Reader.java

+package cz.muni.fi.pb162.hw03.csv.impl;
+
+import cz.muni.fi.pb162.hw03.csv.CsvReader;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.nio.charset.Charset;
+import java.util.Arrays;
+import java.util.List;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
+
+import static cz.muni.fi.pb162.hw03.csv.Messages.INVALID_FORMAT;
+
+public class Reader implements CsvReader<List<String>> {
+    private final BufferedReader reader;
+    private final String delimiter;
+    public Reader(InputStream is, Charset charset, String delimiter){
+        reader = new BufferedReader(new InputStreamReader(is,charset));
+        this.delimiter = delimiter;
+    }
+
+
+    @Override
+    public void forEach(Consumer consumer) throws IOException {
+        while (reader.ready()){
+            consumer.accept(read());
+        }
+    }
+
+    @Override
+    public void close() throws IOException {
+        reader.close();
+    }
+
+    @Override
+    public List<String> read() throws IOException {
+        return reader.ready() ? Arrays.asList(reader.readLine().split(delimiter))
+                .stream()
+                .map(String::trim)
+                .collect(Collectors.toList()) :null;
+    }
+}

src/main/java/cz/muni/fi/pb162/hw03/csv/impl/ReaderWithHeader.java

+package cz.muni.fi.pb162.hw03.csv.impl;
+
+import cz.muni.fi.pb162.hw03.csv.CsvReader;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.charset.Charset;
+import java.util.List;
+import java.util.Map;
+import java.util.function.Consumer;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+
+import static cz.muni.fi.pb162.hw03.csv.Messages.INVALID_FORMAT;
+
+public class ReaderWithHeader implements CsvReader<Map<String, String>> {
+    private final Reader reader;
+    private final List<String> labels;
+
+    public ReaderWithHeader(InputStream is, Charset charset, String delimiter) throws IOException {
+        reader = new Reader(is,charset,delimiter);
+        labels = reader.read();
+    }
+
+    @Override
+    public Map<String, String> read() throws IOException {
+        List<String> s = reader.read();
+        if (s == null){
+            return null;
+        }
+        if (s.size() != labels.size()){
+            throw new IOException(INVALID_FORMAT);
+        }
+        return IntStream.range(0, labels.size()).boxed()
+                .collect(Collectors.toMap(labels::get, s::get));
+    }
+
+    @Override
+    public void forEach(Consumer<Map<String, String>> consumer) throws IOException {
+        Map<String, String> line;
+        while ((line = read()) != null){
+            consumer.accept(line);
+        }
+    }
+
+    @Override
+    public void close() throws IOException {
+        reader.close();
+    }
+}