eugenp · davidmartinezbarua · Apr 10, 2025 · Mar 11, 2025 · Mar 14, 2025
diff --git a/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/ExampleService.java b/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/ExampleService.java
@@ -0,0 +1,16 @@
+package com.baeldung.gettersetter;
+
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+
+public class ExampleService {
+
+    public <T> T getField(Supplier<T> getter) {
+        return getter.get();
+    }
+
+    public <T> void setField(Consumer<T> setter, T value) {
+        setter.accept(value);
+    }
+
+}
diff --git a/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/NonSimpleClass.java b/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/NonSimpleClass.java
@@ -0,0 +1,41 @@
+package com.baeldung.gettersetter;
+
+public class NonSimpleClass {
+
+    private Long id;
+    private String name;
+    private String superComplicatedField;
+
+    public NonSimpleClass(Long id, String name, String superComplicatedField) {
+        this.id = id;
+        this.name = name;
+        this.superComplicatedField = superComplicatedField;
+    }
+
+    public NonSimpleClass() {
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getSuperComplicatedField() {
+        return superComplicatedField;
+    }
+
+    public void setSuperComplicatedField(String superComplicatedField) {
+        this.superComplicatedField = superComplicatedField;
+    }
+}
diff --git a/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/SimpleClass.java b/testing-modules/mockito-4/src/main/java/com/baeldung/gettersetter/SimpleClass.java
@@ -0,0 +1,32 @@
+package com.baeldung.gettersetter;
+
+public class SimpleClass {
+
+    private Long id;
+
+    private String name;
+
+    public SimpleClass(Long id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public SimpleClass() {
+    }
+
+    public Long getId() {
+        return id;
+    }
+
+    public void setId(Long id) {
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+}
diff --git a/testing-modules/mockito-4/src/test/java/com/baeldung/gettersetter/ExampleServiceTest.java b/testing-modules/mockito-4/src/test/java/com/baeldung/gettersetter/ExampleServiceTest.java
@@ -0,0 +1,100 @@
+package com.baeldung.gettersetter;
+
+import static org.junit.Assert.assertEquals;
+import static org.mockito.ArgumentMatchers.anyLong;
+import static org.mockito.ArgumentMatchers.anyString;
+import static org.mockito.ArgumentMatchers.eq;
+import static org.mockito.Mockito.doAnswer;
+import static org.mockito.Mockito.doNothing;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
+
+import org.junit.Test;
+import org.mockito.stubbing.Answer;
+
+public class ExampleServiceTest {
+
+    @Test
+    public void givenMockedSimpleClass_whenInvokingSettersGetters_thenInvokeMockedSettersGetters() {
+        Long mockId = 12L;
+        String mockName = "I'm 12";
+        SimpleClass simpleMock = mock(SimpleClass.class);
+        when(simpleMock.getId()).thenReturn(mockId);
+        when(simpleMock.getName()).thenReturn(mockName);
+        doNothing().when(simpleMock)
+            .setId(anyLong());
+        doNothing().when(simpleMock)
+            .setName(anyString());
+        ExampleService srv = new ExampleService();
+        srv.setField(simpleMock::setId, 11L);
+        srv.setField(simpleMock::setName, "I'm 11");
+        assertEquals(srv.getField(simpleMock::getId), mockId);
+        assertEquals(srv.getField(simpleMock::getName), mockName);
+        verify(simpleMock).getId();
+        verify(simpleMock).getName();
+        verify(simpleMock).setId(eq(11L));
+        verify(simpleMock).setName(eq("I'm 11"));
+    }
+
+    @Test
+    public void givenActualSimpleClass_whenInvokingSettersGetters_thenInvokeActualSettersGetters() {
+        Long id = 1L;
+        String name = "I'm 1";
+        SimpleClass simple = new SimpleClass(id, name);
+        ExampleService srv = new ExampleService();
+        srv.setField(simple::setId, 2L);
+        srv.setField(simple::setName, "I'm 2");
+        assertEquals(srv.getField(simple::getId), simple.getId());
+        assertEquals(srv.getField(simple::getName), simple.getName());
+    }
+
+    @Test
+    public void givenNonSimpleClass_whenInvokingGetName_thenReturnMockedName() {
+        NonSimpleClass nonSimple = mock(NonSimpleClass.class);
+        when(nonSimple.getName()).thenReturn("Meredith");
+        ExampleService srv = new ExampleService();
+        assertEquals(srv.getField(nonSimple::getName), "Meredith");
+        verify(nonSimple).getName();
+    }
+
+    static class Wrapper<T> {
+
+        private T value;
+
+        Wrapper(T value) {
+            this.value = value;
+        }
+
+        Wrapper(Class<T> value) {
+
+        }
+
+        T get() {
+            return value;
+        }
+
+        void set(T value) {
+            this.value = value;
+        }
+
+    }
+
+    @Test
+    public void givenNonSimpleClass_whenInvokingGetName_thenReturnTheLatestNameSet() {
+        Wrapper<String> nameWrapper = new Wrapper<>(String.class);
+        NonSimpleClass nonSimple = mock(NonSimpleClass.class);
+        when(nonSimple.getName()).thenAnswer((Answer<String>) invocationOnMock -> nameWrapper.get());
+        doAnswer(invocation -> {
+            nameWrapper.set(invocation.getArgument(0));
+            return null;
+        }).when(nonSimple)
+            .setName(anyString());
+        ExampleService srv = new ExampleService();
+        srv.setField(nonSimple::setName, "John");
+        assertEquals(srv.getField(nonSimple::getName), "John");
+        srv.setField(nonSimple::setName, "Nick");
+        assertEquals(srv.getField(nonSimple::getName), "Nick");
+    }
+
+}