Add int-to-boolean conversion methods to KiwiJdbc

* Add overloaded booleanFromInt methods. Both accept a ResultSet
  and a String columnName, but one accepts a BooleanConversionOption
  argument while the other doesn't. The one that does not accept
  a BooleanConversionOption uses the ZERO_OR_ONE option.

Closes #1046

src/main/java/org/kiwiproject/jdbc/KiwiJdbc.java

@@ -333,6 +333,36 @@ public static boolean booleanFromLong(ResultSet rs, String columnName, BooleanCo
         return KiwiPrimitives.booleanFromLong(rs.getLong(columnName), option);
     }
 
+    /**
+     * Converts an int value in the specified column to a boolean. The database value must be zero, one
+     * or NULL.
+     *
+     * @param rs         the ResultSet
+     * @param columnName the column name
+     * @return true if the database value is one, or false if it is zero or NULL
+     * @throws IllegalArgumentException if the value in the column is not zero, one, or NULL
+     * @throws SQLException             if there is any error getting the value from the database
+     * @see #booleanFromInt(ResultSet, String, BooleanConversionOption)
+     */
+    public static boolean booleanFromInt(ResultSet rs, String columnName) throws SQLException {
+        return booleanFromInt(rs, columnName, BooleanConversionOption.ZERO_OR_ONE);
+    }
+
+    /**
+     * Converts an int value in the specified column to a boolean using the given {@link BooleanConversionOption}.
+     *
+     * @param rs         the ResultSet
+     * @param columnName the column name
+     * @param option     how to convert the int value into a boolean
+     * @return the converted value, determined using the conversion option
+     * @throws SQLException if there is any error getting the value from the database
+     */
+    public static boolean booleanFromInt(ResultSet rs, String columnName, BooleanConversionOption option)
+            throws SQLException {
+
+        return KiwiPrimitives.booleanFromInt(rs.getInt(columnName), option);
+    }
+
     /**
      * Sets the {@link Timestamp} value in a null-safe manner by using the {@link PreparedStatement#setNull(int, int)}
      * method for {@code null} values. Uses {@link Types#TIMESTAMP} as the SQL type.

src/test/java/org/kiwiproject/jdbc/KiwiJdbcTest.java

@@ -588,6 +588,65 @@ void shouldConvert_WithBooleanConversionOption(long value,
         }
     }
 
+    @Nested
+    class BooleanFromInt {
+
+        @ParameterizedTest
+        @CsvSource(textBlock = """
+                1, true,
+                0, false
+                """)
+        void shouldConvert_WithZeroOrOneConversionOption(int value, boolean expectedResult) throws SQLException {
+            var resultSet = newMockResultSet();
+            when(resultSet.getInt(anyString())).thenReturn(value);
+
+            assertThat(KiwiJdbc.booleanFromInt(resultSet, "is_admin"))
+                    .isEqualTo(expectedResult);
+
+            verify(resultSet).getInt("is_admin");
+            verifyNoMoreInteractions(resultSet);
+        }
+
+        @ParameterizedTest
+        @ValueSource(ints = { -1, 2, 4, 42 })
+        void shouldThrowIllegalArgument_WhenValueFromResultSet_IsNotZeroOrOne_WithZeroOrOneConversionOption(int value)
+                throws SQLException {
+
+            var resultSet = newMockResultSet();
+            when(resultSet.getInt(anyString())).thenReturn(value);
+
+            assertThatIllegalArgumentException()
+                    .isThrownBy(() -> KiwiJdbc.booleanFromInt(resultSet, "is_active"))
+                    .withMessage("value must be 0 or 1, but found %d", value);
+
+            verify(resultSet).getInt("is_active");
+            verifyNoMoreInteractions(resultSet);
+        }
+
+        @ParameterizedTest
+        @CsvSource(textBlock = """
+                1, ZERO_OR_ONE, true,
+                1, NON_ZERO_AS_TRUE, true,
+                -1, NON_ZERO_AS_TRUE, true,
+                2, NON_ZERO_AS_TRUE, true,
+                1000, NON_ZERO_AS_TRUE, true,
+                0, ZERO_OR_ONE, false,
+                0, NON_ZERO_AS_TRUE, false
+                """)
+        void shouldConvert_WithBooleanConversionOption(int value,
+                                                       BooleanConversionOption option,
+                                                       boolean expectedResult) throws SQLException {
+            var resultSet = newMockResultSet();
+            when(resultSet.getInt(anyString())).thenReturn(value);
+
+            assertThat(KiwiJdbc.booleanFromInt(resultSet, "is_admin", option))
+                    .isEqualTo(expectedResult);
+
+            verify(resultSet).getInt("is_admin");
+            verifyNoMoreInteractions(resultSet);
+        }
+    }
+
     @Nested
     class NullSafeSetInt {