@Test
public void testToString() {

    Assert.assertEquals(null, StringUtils.toString(null));
    Assert.assertEquals("Bean:11", StringUtils.toString(new Bean("11")));
    Assert.assertEquals(null, StringUtils.toString((Object) null, null));
    Assert.assertEquals("1", StringUtils.toString((Object) null, "1"));
    Assert.assertEquals("Bean:11", StringUtils.toString(new Bean("11"), null));
    Assert.assertEquals(null, StringUtils.objectsToString(null));
    Assert.assertEquals("[]", StringUtils.objectsToString(new Object[0]));
    Assert.assertEquals("[1,22]", StringUtils.objectsToString(new Object[] { 1, "22" }));
    Assert.assertEquals("[1,Bean:11]", StringUtils.objectsToString(new Object[] { 1, new Bean("11") }));
}