BAEL-4991 added in code for Java 9 private method introduction (#10884)

* BAEL-4991 added in code for Java 9 private method introduction * BAEL-4991 added unit tests for java 9 private methods in interface article Co-authored-by: Liam Garvie <liamgarvie@Liams-MacBook-Pro.local>
2021-06-09 17:31:16 +01:00
parent a8890ebdca
commit 541faa3a97
3 changed files with 70 additions and 0 deletions
@@ -0,0 +1,38 @@
+package com.baeldung.java9.interfaces;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class CustomFooUnitTest {
+    private ByteArrayOutputStream outContent = new ByteArrayOutputStream();
+    private PrintStream originalOut = System.out;
+
+    @BeforeEach
+    void setup() {
+        System.setOut(new PrintStream(outContent));
+    }
+
+    @AfterEach
+    void tearDown() {
+        System.setOut(originalOut);
+    }
+
+    @Test
+    void givenACustomFooObject_whenCallingDefaultMethodBar_thenExpectedStringIsWrittenToSystemOut() {
+        CustomFoo customFoo = new CustomFoo();
+        customFoo.bar();
+        assertThat(outContent.toString()).isEqualTo("Hello world!");
+    }
+
+    @Test
+    void givenAFooInterface_whenCallingStaticMethodBuzz_thenExpectedStringIsWrittenToSystemOut() {
+        Foo.buzz();
+        assertThat(outContent.toString()).isEqualTo("Hello static world!");
+    }
+}