eugenp · jzheaux · May 7, 2025 · Apr 25, 2025 · Apr 25, 2025 · Apr 25, 2025
diff --git a/core-java-modules/core-java-io-conversions/pom.xml b/core-java-modules/core-java-io-conversions/pom.xml
@@ -38,7 +38,7 @@
     </build>
 
     <properties>
-        <opencsv.version>5.8</opencsv.version>
+        <opencsv.version>5.9</opencsv.version>
     </properties>
 
-</project>
+</project>
diff --git a/...ules/core-java-io-conversions/src/test/java/com/baeldung/csv/CustomCSVParserUnitTest.java b/...ules/core-java-io-conversions/src/test/java/com/baeldung/csv/CustomCSVParserUnitTest.java
@@ -0,0 +1,79 @@
+package com.baeldung.csv;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+
+
+public class CustomCSVParserUnitTest {
+    public static final String COMMA_DELIMITER = ",";
+
+    public static final String CSV_FILE  = "src/test/resources/book3.csv";
+
+    public static final List<List<String>> EXPECTED_ARRAY = Collections.unmodifiableList(new ArrayList<List<String>>() {
+        {
+            add(new ArrayList<String>() {
+                {
+                    add("Kom, Mary");
+                    add("Unbreakable");
+                }
+            });
+            add(new ArrayList<String>() {
+                {
+                    add("Isapuari, Kapil");
+                    add("Farishta");
+                }
+            });
+        }
+    });
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenCustomCSVParser_thenContentsAsExpected() throws IOException {
+        List<List<String>> records = new ArrayList<List<String>>();
+        try (BufferedReader br = new BufferedReader(new FileReader(CSV_FILE))) {
+            String line = "";
+            while ((line = br.readLine()) != null) {
+                records.add(parseLine(line));
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+            Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                .toArray(),
+                records.get(i)
+                    .toArray());
+        }
+    }
+
+    private static List<String> parseLine(String line) {
+        List<String> values = new ArrayList<>();
+        boolean inQuotes = false;
+        StringBuilder currentValue = new StringBuilder();
+
+        for (char c : line.toCharArray()) {
+            if (c == '"') {
+                inQuotes = !inQuotes;
+            } else if (c == ',' && !inQuotes) {
+                values.add(currentValue.toString());
+                currentValue = new StringBuilder();
+            } else {
+                currentValue.append(c);
+            }
+        }
+        values.add(currentValue.toString());
+        return values;
+    }
+}
diff --git a/...dules/core-java-io-conversions/src/test/java/com/baeldung/csv/ReadCSVInArrayUnitTest.java b/...dules/core-java-io-conversions/src/test/java/com/baeldung/csv/ReadCSVInArrayUnitTest.java
@@ -40,6 +40,7 @@ public class ReadCSVInArrayUnitTest {
         }
     });
 
+
     @Test
     public void givenCSVFile_whenBufferedReader_thenContentsAsExpected() throws IOException {
         List<List<String>> records = new ArrayList<List<String>>();

diff --git a/...conversions/src/test/java/com/baeldung/csv/ReadCSVWithCommaInValuesIntoArrayUnitTest.java b/...conversions/src/test/java/com/baeldung/csv/ReadCSVWithCommaInValuesIntoArrayUnitTest.java
@@ -0,0 +1,176 @@
+package com.baeldung.csv;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileNotFoundException;
+import java.io.FileReader;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+import java.util.Scanner;
+import java.util.stream.Collectors;
+import java.util.stream.Stream;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import com.opencsv.CSVReader;
+
+public class ReadCSVWithCommaInValuesIntoArrayUnitTest {
+    public static final String COMMA_DELIMITER = "\\|";
+    public static final String CSV_FILE = "src/test/resources/book2.csv";
+    public static final String CSV_FILE_OpenCSV = "src/test/resources/book3.csv";
+
+    public static final List<List<String>> EXPECTED_ARRAY = Collections.unmodifiableList(new ArrayList<List<String>>() {
+        {
+            add(new ArrayList<String>() {
+                {
+                    add("\"Kom, Mary\"");
+                    add("Unbreakable");
+                }
+            });
+            add(new ArrayList<String>() {
+                {
+                    add("\"Isapuari, Kapil\"");
+                    add("Farishta");
+                }
+            });
+        }
+    });
+
+    public static final List<List<String>> EXPECTED_ARRAY_OpenCSV = Collections.unmodifiableList(new ArrayList<List<String>>() {
+        {
+            add(new ArrayList<String>() {
+                {
+                    add("Kom, Mary");
+                    add("Unbreakable");
+                }
+            });
+            add(new ArrayList<String>() {
+                {
+                    add("Isapuari, Kapil");
+                    add("Farishta");
+                }
+            });
+        }
+    });
+
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenOpencsv_thenContentsAsExpected() throws IOException {
+        List<List<String>> records = new ArrayList<List<String>>();
+        try (CSVReader csvReader = new CSVReader(new FileReader(CSV_FILE_OpenCSV));) {
+            String[] values = null;
+            while ((values = csvReader.readNext()) != null) {
+                records.add(Arrays.asList(values));
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        for (int i = 0; i < EXPECTED_ARRAY_OpenCSV.size(); i++) {
+            Assert.assertArrayEquals(EXPECTED_ARRAY_OpenCSV.get(i)
+                .toArray(),
+                records.get(i)
+                    .toArray());
+        }
+    }
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenBufferedReader_thenContentsAsExpected() throws IOException {
+        List<List<String>> records = new ArrayList<List<String>>();
+        try (BufferedReader br = new BufferedReader(new FileReader(CSV_FILE))) {
+            String line = "";
+            while ((line = br.readLine()) != null) {
+                String[] values = line.split(COMMA_DELIMITER);
+                records.add(Arrays.asList(values));
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+            Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                .toArray(),
+                records.get(i)
+                    .toArray());
+        }
+    }
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenScanner_thenContentsAsExpected() throws IOException {
+        List<List<String>> records = new ArrayList<List<String>>();
+        try (Scanner scanner = new Scanner(new File(CSV_FILE));) {
+            while (scanner.hasNextLine()) {
+                records.add(getRecordFromLine(scanner.nextLine()));
+            }
+        } catch (FileNotFoundException e) {
+            e.printStackTrace();
+        }
+        for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+            Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                .toArray(),
+                records.get(i)
+                    .toArray());
+        }
+    }
+
+    private List<String> getRecordFromLine(String line) {
+        List<String> values = new ArrayList<String>();
+        try (Scanner rowScanner = new Scanner(line)) {
+            rowScanner.useDelimiter(COMMA_DELIMITER);
+            while (rowScanner.hasNext()) {
+                values.add(rowScanner.next());
+            }
+        }
+        return values;
+    }
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenUsingFilesReadAllLinesMethod_thenContentsAsExpected() throws IOException {
+        List<List<String>> records = Files.readAllLines(Paths.get(CSV_FILE))
+          .stream()
+          .map(line -> Arrays.asList(line.split(COMMA_DELIMITER)))
+          .collect(Collectors.toList());
+
+        for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+            Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                .toArray(),
+                records.get(i)
+                    .toArray());
+        }
+    }
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenUsingFilesNewBufferedReaderMethod_thenContentsAsExpected() throws IOException {
+        try (BufferedReader reader = Files.newBufferedReader(Paths.get(CSV_FILE))) {
+            List<List<String>> records = reader.lines()
+              .map(line -> Arrays.asList(line.split(COMMA_DELIMITER)))
+              .collect(Collectors.toList());
+
+            for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+                Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                    .toArray(),
+                    records.get(i)
+                        .toArray());
+            }
+        }
+    }
+
+    @Test
+    public void givenCSVFileWithCommaInValues_whenUsingFilesLinesMethod_thenContentsAsExpected() throws IOException {
+        try (Stream<String> lines = Files.lines(Paths.get(CSV_FILE))) {
+            List<List<String>> records = lines.map(line -> Arrays.asList(line.split(COMMA_DELIMITER)))
+              .collect(Collectors.toList());
+
+            for (int i = 0; i < EXPECTED_ARRAY.size(); i++) {
+                Assert.assertArrayEquals(EXPECTED_ARRAY.get(i)
+                    .toArray(),
+                    records.get(i)
+                        .toArray());
+            }
+        }
+    }
+}
diff --git a/core-java-modules/core-java-io-conversions/src/test/resources/book2.csv b/core-java-modules/core-java-io-conversions/src/test/resources/book2.csv
@@ -0,0 +1,2 @@
+"Kom, Mary"|Unbreakable
+"Isapuari, Kapil"|Farishta
diff --git a/core-java-modules/core-java-io-conversions/src/test/resources/book3.csv b/core-java-modules/core-java-io-conversions/src/test/resources/book3.csv
@@ -0,0 +1,2 @@
+"Kom, Mary",Unbreakable
+"Isapuari, Kapil",Farishta
-Original file line number
+Diff line change
@@ Expand Up / @@ -40,6 +40,7 @@ public class ReadCSVInArrayUnitTest { @@
             }
         });
         @Test
         public void givenCSVFile_whenBufferedReader_thenContentsAsExpected() throws IOException {
             List<List<String>> records = new ArrayList<List<String>>();
@@ Expand Down @@
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		"Kom, Mary"\|Unbreakable
		"Isapuari, Kapil"\|Farishta
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		"Kom, Mary",Unbreakable
		"Isapuari, Kapil",Farishta