@Test
    public void testInvalidVersionParse() {

        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("potato"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION___"));

        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION__2_3"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_1__3"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_1_2_"));

        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_A_2_3"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_1_B_3"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("VERSION_1_2_C"));

        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("_1_2_3"));
        Assert.assertNull(GuacamoleProtocolVersion.parseVersion("version_1_2_3"));

    }
Verifies that invalid version strings fail to parse.
guacamole-common/src/test/java/org/apache/guacamole/protocol/GuacamoleProtocolVersionTest.java