Merge pull request eugenp#8049 from vatsalgosar/BAEL-3143

BAEL 3143

Author: eric-martin

core-java-modules/core-java-io-2/src/test/java/com/baeldung/scanner/JavaScannerUnitTest.java

@@ -0,0 +1,44 @@
+package com.baeldung.scanner;
+
+import static org.junit.Assert.assertEquals;
+
+import java.util.NoSuchElementException;
+import java.util.Scanner;
+
+import org.junit.Test;
+
+public class JavaScannerUnitTest {
+
+    @Test
+    public void whenReadingLines_thenCorrect() {
+        String input = "Scanner\nTest\n";
+        try (Scanner scanner = new Scanner(input)) {
+            assertEquals("Scanner", scanner.nextLine());
+            assertEquals("Test", scanner.nextLine());
+        }
+    }
+
+    @Test
+    public void whenReadingPartialLines_thenCorrect() {
+        String input = "Scanner\n";
+        try (Scanner scanner = new Scanner(input)) {
+            scanner.useDelimiter("");
+            scanner.next();
+            assertEquals("canner", scanner.nextLine());
+        }
+    }
+
+    @Test(expected = NoSuchElementException.class)
+    public void givenNoNewLine_whenReadingNextLine_thenThrowNoSuchElementException() {
+        try (Scanner scanner = new Scanner("")) {
+            String result = scanner.nextLine();
+        }
+    }
+
+    @Test(expected = IllegalStateException.class)
+    public void givenScannerIsClosed_whenReadingNextLine_thenThrowIllegalStateException() {
+        Scanner scanner = new Scanner("");
+        scanner.close();
+        String result = scanner.nextLine();
+    }
+}