Add KiwiBooleans and KiwiInteger util classes (#1125)

* KiwiBooleans contains methods to convert Boolean into boolean
* KiwiIntegers contains methods to convert Integer to int

Closes #1123
Closes #1124

src/main/java/org/kiwiproject/base/KiwiBooleans.java

@@ -0,0 +1,47 @@
+package org.kiwiproject.base;
+
+import static java.util.Objects.isNull;
+
+import lombok.experimental.UtilityClass;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+/**
+ * Utilities for working with {@link Boolean} wrapper objects.
+ */
+@UtilityClass
+public class KiwiBooleans {
+
+    /**
+     * Return the {@code boolean} value of the {@link Boolean} when non-null,
+     * otherwise return {@code true}.
+     *
+     * @param booleanObject the possibly null Boolean object
+     * @return the boolean value of the Boolean object when non-null, otherwise {@code true}
+     */
+    public static boolean toBooleanOrTrue(@Nullable Boolean booleanObject) {
+        return toBooleanOrDefault(booleanObject, true);
+    }
+
+     /**
+     * Return the {@code boolean} value of the {@link Boolean} when non-null,
+     * otherwise return {@code false}.
+     *
+     * @param booleanObject the possibly null Boolean object
+     * @return the boolean value of the Boolean object when non-null, otherwise {@code false}
+     */
+    public static boolean toBooleanOrFalse(@Nullable Boolean booleanObject) {
+        return toBooleanOrDefault(booleanObject, false);
+    }
+
+    /**
+     * Return the {@code boolean} value of the {@link Boolean} when non-null,
+     * otherwise return the default value.
+     *
+     * @param booleanObject the possibly null Boolean object
+     * @param defaultValue the value to use when the Boolean argument is null
+     * @return the boolean value of the Boolean object when non-null, otherwise {@code defaultValue}
+     */
+    public static boolean toBooleanOrDefault(@Nullable Boolean booleanObject, boolean defaultValue) {
+        return isNull(booleanObject) ? defaultValue : booleanObject;
+    }
+}

src/main/java/org/kiwiproject/base/KiwiIntegers.java

@@ -0,0 +1,36 @@
+package org.kiwiproject.base;
+
+import static java.util.Objects.isNull;
+
+import lombok.experimental.UtilityClass;
+import org.checkerframework.checker.nullness.qual.Nullable;
+
+/**
+ * Utilities for working with {@link Integer} wrapper objects.
+ */
+@UtilityClass
+public class KiwiIntegers {
+
+    /**
+     * Return the {@code int} value of the {@link Integer} when non-null,
+     * otherwise return zero.
+     *
+     * @param integerObject the possibly null Integer object
+     * @return the {@code int} value of the Integer object when non-null, otherwise {@code 0} (zero)
+     */
+    public static int toIntOrZero(@Nullable Integer integerObject) {
+        return toIntOrDefault(integerObject, 0);
+    }
+
+    /**
+     * Return the {@code int} value of the {@link Integer} when non-null,
+     * otherwise return the default value.
+     *
+     * @param integerObject the possibly null Integer object
+     * @param defaultValue the value to use when the Integer argument is null
+     * @return the {@code int} value of the Integer object when non-null, otherwise {@code defaultValue}
+     */
+    public static int toIntOrDefault(@Nullable Integer integerObject, int defaultValue) {
+        return isNull(integerObject) ? defaultValue : integerObject;
+    }
+}

src/test/java/org/kiwiproject/base/KiwiBooleansTest.java

@@ -0,0 +1,47 @@
+package org.kiwiproject.base;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+@DisplayName("KiwiBooleans")
+class KiwiBooleansTest {
+
+    @ParameterizedTest(name = "Boolean: {0}, expect: {1}")
+    @CsvSource(textBlock = """
+        TRUE, true,
+        FALSE, false,
+        null, true
+        """, nullValues = "null")
+    void toBooleanOrTrue(Boolean booleanObject, boolean expectedResult) {
+        assertThat(KiwiBooleans.toBooleanOrTrue(booleanObject))
+                .isEqualTo(expectedResult);
+    }
+
+    @ParameterizedTest(name = "Boolean: {0}, expect: {1}")
+    @CsvSource(textBlock = """
+        TRUE, true,
+        FALSE, false,
+        null, false
+        """, nullValues = "null")
+    void toBooleanOrFalse(Boolean booleanObject, boolean expectedResult) {
+        assertThat(KiwiBooleans.toBooleanOrFalse(booleanObject))
+                .isEqualTo(expectedResult);
+    }
+
+    @ParameterizedTest(name = "Boolean: {0}, default: {1}, expect: {2}")
+    @CsvSource(textBlock = """
+        TRUE, true, true
+        TRUE, false, true
+        FALSE, true, false
+        FALSE, true, false
+        null, true, true
+        null, false, false
+        """, nullValues = "null")
+    void toBooleanOrDefault(Boolean booleanObject, boolean defaultValue, boolean expectedResult) {
+        assertThat(KiwiBooleans.toBooleanOrDefault(booleanObject, defaultValue))
+                .isEqualTo(expectedResult);
+    }
+}

src/test/java/org/kiwiproject/base/KiwiIntegersTest.java

@@ -0,0 +1,36 @@
+package org.kiwiproject.base;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.CsvSource;
+
+@DisplayName("KiwiIntegers")
+class KiwiIntegersTest {
+
+    @ParameterizedTest(name = "Integer: {0}, expect: {1}")
+    @CsvSource(textBlock = """
+        1, 1
+        42, 42
+        -10, -10
+        null, 0
+        """, nullValues = "null")
+    void toIntOrZero(Integer integerObject, int expectedResult) {
+        assertThat(KiwiIntegers.toIntOrZero(integerObject))
+                .isEqualTo(expectedResult);
+    }
+
+    @ParameterizedTest(name = "Integer: {0}, default: {1}, expect: {2}")
+    @CsvSource(textBlock = """
+        10, 0, 10
+        42, 11, 42
+        -10, 5, -10
+        null, 0, 0
+        null, 42, 42
+        """, nullValues = "null")
+    void toIntOrDefault(Integer integerObject, int defaultValue, int expectedResult) {
+        assertThat(KiwiIntegers.toIntOrDefault(integerObject, defaultValue))
+                .isEqualTo(expectedResult);
+    }
+}