[[sec:what_plugins_do]]
Plugins introduce new tasks (e.g., `JavaCompile`), domain objects (e.g., `SourceSet`), conventions (e.g., locating Java source at `src/main/java`), and extend core or other plugin objects.

/*
 * Written by Doug Lea with assistance from members of JCP JSR-166
 * Expert Group and released to the public domain, as explained at
 * http://creativecommons.org/publicdomain/zero/1.0/
 * Other contributors include Andrew Wright, Jeffrey Hayes,
 * Pat Fisher, Mike Judd.
 */

/*
 * Source:
 * http://gee.cs.oswego.edu/cgi-bin/viewcvs.cgi/jsr166/src/test/tck/JSR166TestCase.java?revision=1.90

				}
				for _, addr := range addrs {
					domainIPs.Add(addr)
				}
			}
			domainIPs.Add(endpoint)
		}
		updateDomainIPs(domainIPs)
	} else {
		// Add found interfaces IP address to global domain IPS,
		// loopback addresses will be naturally dropped.
		domainIPs := mustGetLocalIP4()
		for _, host := range globalEndpoints.Hostnames() {
			domainIPs.Add(host)
		}
		updateDomainIPs(domainIPs)
	}

		{"[::1]:80", "::1", "80"},
		{"[::1]", "::1", ""},
		{"[::1]:", "::1", ""},
		{"localhost", "localhost", ""},
		{"localhost:443", "localhost", "443"},
		{"some.super.long.domain.example.org:8080", "some.super.long.domain.example.org", "8080"},
		{"[2001:0db8:85a3:0000:0000:8a2e:0370:7334]:17000", "2001:0db8:85a3:0000:0000:8a2e:0370:7334", "17000"},

		// This can be overridden by ingress.defaultEndpoint.
		// * 127.0.0.1: send to localhost
		// * 0.0.0.0: send to INSTANCE_IP
		// * unix:///...: send to configured unix domain socket
		endpointAddress := ""
		port := 0
		if strings.HasPrefix(ingressListener.DefaultEndpoint, model.UnixAddressPrefix) {
			// this is a UDS endpoint. assign it as is

	// of pods into each bucket.
	// We define a domain as a particular instance of a topology.
	// Also, we define an eligible domain as a domain whose nodes meet the requirements of
	// nodeAffinityPolicy and nodeTaintsPolicy.
	// e.g. If TopologyKey is "kubernetes.io/hostname", each Node is a domain of that topology.
	// And, if TopologyKey is "topology.kubernetes.io/zone", each zone is a domain of that topology.
	// It's a required field.

	}, {
		testName: "RunAsUserName's NetBios Domain is too long",
		windowsOptions: &core.WindowsSecurityContextOptions{
			RunAsUserName: toPtr("NetBios " + strings.Repeat("a", 8) + "\\user"),
		},
		expectedErrorSubstring: "runAsUserName's Domain doesn't match the NetBios",
	}, {
		testName: "RunAsUserName's DNS Domain is too long",
		windowsOptions: &core.WindowsSecurityContextOptions{

   * which contained the following notice:
   *
   * Written by Doug Lea with assistance from members of JCP JSR-166 Expert Group and released to
   * the public domain, as explained at http://creativecommons.org/publicdomain/zero/1.0/
   *
   * Other contributors include Andrew Wright, Jeffrey Hayes, Pat Fisher, Mike Judd.
   */

  /**

		// So we bump X to 511, so that the resulting IP is 240.240.2.1
		if x%255 == 0 {
			x++
		}
		if v, ok := hnMap[n]; ok {
			log.Debugf("Reuse IP for domain %s", n)
			setAutoAllocatedIPs(svc, v)
		} else {
			var thirdOctect, fourthOctect int
			thirdOctect = x / 255
			fourthOctect = x % 255
			pair := octetPair{thirdOctect, fourthOctect}

  // value is the reserved string `kubernetes.io/job-controller`, but skips
  // reconciling Jobs with a custom value for this field.
  // The value must be a valid domain-prefixed path (e.g. acme.io/foo) -
  // all characters before the first "/" must be a valid subdomain as defined
  // by RFC 1123. All characters trailing the first "/" must be valid HTTP Path