Implemented IntFromBoolean UDF

Author: rgibaiev

Diff for: ksqldb-engine/src/main/java/io/confluent/ksql/function/udf/conversions/IntFromBoolean.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2023 Confluent Inc.
+ *
+ * Licensed under the Confluent Community License; you may not use this file
+ * except in compliance with the License.  You may obtain a copy of the License at
+ *
+ * http://www.confluent.io/confluent-community-license
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OF ANY KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations under the License.
+ */
+
+package io.confluent.ksql.function.udf.conversions;
+
+import io.confluent.ksql.function.FunctionCategory;
+import io.confluent.ksql.function.udf.Udf;
+import io.confluent.ksql.function.udf.UdfDescription;
+import io.confluent.ksql.function.udf.UdfParameter;
+
+@UdfDescription(
+    name = "int_from_boolean",
+    category = FunctionCategory.CONVERSIONS,
+    description = "Converts a Boolean value to an Integer value"
+)
+public class IntFromBoolean {
+
+  @Udf(description = "Converts a Boolean value to an Integer value")
+  public Integer intFromBoolean(
+      @UdfParameter(description = "The Boolean value to convert.")
+      final Boolean bool
+  ) {
+    if (bool == null) {
+      return null;
+    }
+    return Boolean.TRUE.equals(bool) ? 1 : 0;
+  }
+}

Diff for: ksqldb-engine/src/test/java/io/confluent/ksql/function/udf/conversions/IntFromBooleanTest.java

@@ -0,0 +1,27 @@
+package io.confluent.ksql.function.udf.conversions;
+
+import org.junit.Test;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.hamcrest.Matchers.is;
+import static org.hamcrest.Matchers.nullValue;
+
+public class IntFromBooleanTest {
+  private final IntFromBoolean udf = new IntFromBoolean();
+
+  @Test
+  public void shouldReturnNullOnNullBoolean() {
+    assertThat(udf.intFromBoolean(null), is(nullValue()));
+  }
+
+  @Test
+  public void shouldConvertTrueToInteger() {
+    assertThat(udf.intFromBoolean(Boolean.TRUE), is(1));
+  }
+
+  @Test
+  public void shouldConvertFalseToInteger() {
+    assertThat(udf.intFromBoolean(Boolean.FALSE), is(0));
+  }
+
+}