Bael 2019 static vs dynamic binding (#4807)

* adding the required classes for binding example

* completed test class for AnimalActivityUnitTest static functions

* changes to example so that they don't seem to be a replica of https://stackoverflow.com/questions/19017258/static-vs-dynamic-binding-in-java

* refactoring and removing unnecessary file

* revert changes to RegexUnitTest

core-java/src/main/java/com/baeldung/binding/Animal.java

@@ -0,0 +1,23 @@
+package com.baeldung.binding;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Created by madhumita.g on 25-07-2018.
+ */
+public class Animal {
+
+    final static Logger logger = LoggerFactory.getLogger(Animal.class);
+
+    public void makeNoise() {
+        logger.info("generic animal noise");
+    }
+
+    public void makeNoise(Integer repetitions) {
+        while(repetitions != 0) {
+            logger.info("generic animal noise countdown " + repetitions);
+            repetitions -= 1;
+        }
+    }
+}

core-java/src/main/java/com/baeldung/binding/AnimalActivity.java

@@ -0,0 +1,43 @@
+package com.baeldung.binding;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Created by madhumita.g on 25-07-2018.
+ */
+public class AnimalActivity {
+
+    final static Logger logger = LoggerFactory.getLogger(AnimalActivity.class);
+
+
+    public static void sleep(Animal animal) {
+        logger.info("Animal is sleeping");
+    }
+
+    public static void sleep(Cat cat) {
+        logger.info("Cat is sleeping");
+    }
+
+    public static void main(String[] args) {
+
+        Animal animal = new Animal();
+
+        //calling methods of animal object
+        animal.makeNoise();
+
+        animal.makeNoise(3);
+
+
+        //assigning a dog object to reference of type Animal
+        Animal catAnimal = new Cat();
+
+        catAnimal.makeNoise();
+
+        // calling static function
+        AnimalActivity.sleep(catAnimal);
+
+        return;
+
+    }
+}

core-java/src/main/java/com/baeldung/binding/Cat.java

@@ -0,0 +1,18 @@
+package com.baeldung.binding;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Created by madhumita.g on 25-07-2018.
+ */
+public class Cat extends Animal {
+
+    final static Logger logger = LoggerFactory.getLogger(Cat.class);
+
+    public void makeNoise() {
+
+        logger.info("meow");
+    }
+
+}

core-java/src/test/java/com/baeldung/binding/AnimalActivityUnitTest.java

@@ -0,0 +1,95 @@
+package com.baeldung.binding;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.LoggingEvent;
+import ch.qos.logback.core.Appender;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.slf4j.LoggerFactory;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.verify;
+
+/**
+ *https://gist.github.com/bloodredsun/a041de13e57bf3c6c040
+ */
+@RunWith(MockitoJUnitRunner.class)
+
+public class AnimalActivityUnitTest {
+
+    @Mock
+    private Appender mockAppender;
+    @Captor
+    private ArgumentCaptor<LoggingEvent> captorLoggingEvent;
+
+    @Before
+    public void setup() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.addAppender(mockAppender);
+    }
+
+    @After
+    public void teardown() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.detachAppender(mockAppender);
+    }
+
+    @Test
+    public void givenAnimalReference__whenRefersAnimalObject_shouldCallFunctionWithAnimalParam() {
+
+        Animal animal = new Animal();
+
+        AnimalActivity.sleep(animal);
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+        assertThat(loggingEvent.getFormattedMessage(),
+                is("Animal is sleeping"));
+    }
+
+    @Test
+    public void givenDogReference__whenRefersCatObject_shouldCallFunctionWithAnimalParam() {
+
+        Cat cat = new Cat();
+
+        AnimalActivity.sleep(cat);
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+        assertThat(loggingEvent.getFormattedMessage(),
+                is("Cat is sleeping"));
+    }
+
+    @Test
+    public void givenAnimaReference__whenRefersDogObject_shouldCallFunctionWithAnimalParam() {
+
+        Animal cat = new Cat();
+
+        AnimalActivity.sleep(cat);
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+        assertThat(loggingEvent.getFormattedMessage(),
+                is("Animal is sleeping"));
+    }
+}

core-java/src/test/java/com/baeldung/binding/AnimalUnitTest.java

@@ -0,0 +1,86 @@
+package com.baeldung.binding;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.LoggingEvent;
+import ch.qos.logback.core.Appender;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.slf4j.LoggerFactory;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Created by madhumita.g on 01-08-2018.
+ */
+
+@RunWith(MockitoJUnitRunner.class)
+public class AnimalUnitTest {
+    @Mock
+    private Appender mockAppender;
+    @Captor
+    private ArgumentCaptor<LoggingEvent> captorLoggingEvent;
+
+    @Before
+    public void setup() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.addAppender(mockAppender);
+    }
+
+    @After
+    public void teardown() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.detachAppender(mockAppender);
+    }
+
+    @Test
+    public void whenCalledWithoutParameters_shouldCallFunctionMakeNoiseWithoutParameters() {
+
+        Animal animal = new Animal();
+
+        animal.makeNoise();
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+        assertThat(loggingEvent.getFormattedMessage(),
+                is("generic animal noise"));
+    }
+
+    @Test
+    public void whenCalledWithParameters_shouldCallFunctionMakeNoiseWithParameters() {
+
+        Animal animal = new Animal();
+
+        int testValue = 3;
+        animal.makeNoise(testValue);
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        while (testValue != 0) {
+            assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+            assertThat(loggingEvent.getFormattedMessage(),
+                    is("generic animal noise countdown 3\n"
+                            + "generic animal noise countdown 2\n"
+                            + "generic animal noise countdown 1\n"));
+
+            testValue-=1;
+
+        }
+    }
+
+}

core-java/src/test/java/com/baeldung/binding/CatUnitTest.java

@@ -0,0 +1,62 @@
+package com.baeldung.binding;
+
+import ch.qos.logback.classic.Level;
+import ch.qos.logback.classic.Logger;
+import ch.qos.logback.classic.spi.LoggingEvent;
+import ch.qos.logback.core.Appender;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.ArgumentCaptor;
+import org.mockito.Captor;
+import org.mockito.Mock;
+import org.mockito.junit.MockitoJUnitRunner;
+import org.slf4j.LoggerFactory;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.verify;
+
+/**
+ * Created by madhumita.g on 01-08-2018.
+ */
+@RunWith(MockitoJUnitRunner.class)
+public class CatUnitTest {
+
+    @Mock
+    private Appender mockAppender;
+
+    @Captor
+    private ArgumentCaptor<LoggingEvent> captorLoggingEvent;
+
+    @Before
+    public void setup() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.addAppender(mockAppender);
+    }
+
+    @After
+    public void teardown() {
+        final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);
+        logger.detachAppender(mockAppender);
+    }
+
+    @Test
+    public void makeNoiseTest() {
+
+        Cat cat = new Cat();
+
+        cat.makeNoise();
+
+        verify(mockAppender).doAppend(captorLoggingEvent.capture());
+
+        final LoggingEvent loggingEvent = captorLoggingEvent.getValue();
+
+        assertThat(loggingEvent.getLevel(), is(Level.INFO));
+
+        assertThat(loggingEvent.getFormattedMessage(),
+                is("meow"));
+
+    }
+}