# Body - Multiple Parameters { #body-multiple-parameters }

Now that we have seen how to use `Path` and `Query`, let's see more advanced uses of request body declarations.

## Mix `Path`, `Query` and body parameters { #mix-path-query-and-body-parameters }

First, of course, you can mix `Path`, `Query` and request body parameter declarations freely and **FastAPI** will know what to do.

        // Third: sb.length() > 0, add delimiter + "" (sb becomes "middle,")
        assertEquals("middle,", result);
    }

    @Test
    @DisplayName("Should handle mix of empty and null elements")
    void testJoinWithMixedEmptyAndNull() {
        String result = StringUtil.join("-", "", null, "value", "", null);
        // First: "" (sb becomes "")

     */
    @Nonnull
    List<Node> getNodes();

    /**
     * Returns the file paths of all dependencies, regardless of which tool option those paths should be placed on.
     * The returned list may contain a mix of Java class path, Java module path, and other types of path elements.
     * This collection has the same content as {@code getDependencies.values()} except that it does not contain
     * null elements.
     *

        assertEquals(1, param.getValues().length);
        assertEquals("onlyValue", param.getValues()[0]);
    }

    public void test_constructor_withNullAndNonNullValues() {
        // Test with mix of null and non-null values
        String name = "mixedParam";
        String[] values = { "value1", null, "value3", null };
        RequestParameter param = new RequestParameter(name, values);