BAEL-5521 Convert boolean to int in Java (#12017)

* added class for Article examples, created unit tests and modified pom in order to call Apache Commons outside test

* changed parameter to prevent NPE

Co-authored-by: Christian Jaimes <christian.jaimes@oracle>

java-numbers-4/src/test/java/com/baeldung/booleantoint/BooleanToIntUnitTest.java

@@ -0,0 +1,55 @@
+package com.baeldung.booleantoint;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class BooleanToIntUnitTest {
+    @Test
+    void givenBooleanPrimitiveValue_ThenReturnInt() {
+        assertEquals(1, BooleanToInt.booleanPrimitiveToInt(true));
+        assertEquals(0, BooleanToInt.booleanPrimitiveToInt(false));
+    }
+
+    @Test
+    void givenBooleanPrimitiveValue_ThenReturnIntTernary() {
+        assertEquals(1, BooleanToInt.booleanPrimitiveToIntTernary(true));
+        assertEquals(0, BooleanToInt.booleanPrimitiveToIntTernary(false));
+    }
+
+    @Test
+    void givenBooleanObject_ThenReturnInt() {
+        assertEquals(0, BooleanToInt.booleanObjectToInt(false));
+        assertEquals(1, BooleanToInt.booleanObjectToInt(true));
+    }
+
+    @Test
+    void givenBooleanObject_ThenReturnIntInverse() {
+        assertEquals(0, BooleanToInt.booleanObjectToIntInverse(false));
+        assertEquals(1, BooleanToInt.booleanObjectToIntInverse(true));
+    }
+
+    @Test
+    void givenBooleanObject_ThenReturnIntUsingClassMethod() {
+        assertEquals(0, BooleanToInt.booleanObjectMethodToInt(false));
+        assertEquals(1, BooleanToInt.booleanObjectMethodToInt(true));
+    }
+
+    @Test
+    void givenBooleanObject_ThenReturnIntUsingClassMethodInverse() {
+        assertEquals(0, BooleanToInt.booleanObjectMethodToIntInverse(false));
+        assertEquals(1, BooleanToInt.booleanObjectMethodToIntInverse(true));
+    }
+
+    @Test
+    void givenBoolean_ThenReturnIntUsingBooleanUtils() {
+        assertEquals(0, BooleanToInt.booleanUtilsToInt(false));
+        assertEquals(1, BooleanToInt.booleanUtilsToInt(true));
+    }
+
+    @Test
+    void givenBoolean_ThenReturnIntUsingBitwiseOperators() {
+        assertEquals(0, BooleanToInt.bitwiseBooleanToInt(false));
+        assertEquals(1, BooleanToInt.bitwiseBooleanToInt(true));
+    }
+}