This is the model specification for <code>${basedir}/profiles.xml</code>.
  ]]></description>
  <defaults>
    <default>
      <key>package</key>
      <value>org.apache.maven.profiles</value>
    </default>
  </defaults>
  <classes>
    <class rootElement="true" xml.tagName="profilesXml">
      <name>ProfilesRoot</name>
      <version>1.0.0</version>

              "filter_metadata": {
                "istio": {
                  "services": [
                    {
                      "namespace": "default",
                      "name": "ratings",
                      "host": "ratings.default.svc.cluster.local"
                    }
                  ]
                }
              }
            },
            "common_lb_config": {}
          },

		if _, err := config.LookupSite(s[config.SiteSubSys][config.Default], s[config.RegionSubSys][config.Default]); err != nil {
			return err
		}
	case config.APISubSys:
		if _, err := api.LookupConfig(s[config.APISubSys][config.Default]); err != nil {
			return err
		}
	case config.BatchSubSys:
		if _, err := batch.LookupConfig(s[config.BatchSubSys][config.Default]); err != nil {
			return err
		}

// Spec. The `ingressclass.kubernetes.io/is-default-class` annotation can be
// used to indicate that an IngressClass should be considered default. When a
// single IngressClass resource has this annotation set to true, new Ingress
// resources without a class specified will be assigned this default class.
message IngressClass {
  // Standard object's metadata.

    /**
     * name of the bean property used to get/set the field: by default, field name is used.
     * @return the name of the bean property
     */
    @Nonnull
    String name() default "";

    /**
     * alias supported to get parameter value.
     * @return the alias
     */
    @Nonnull
    String alias() default "";

    /**

NAMESPACE     NAME                   REVISION     PROGRAMMED
bookinfo      bookinfo-rev           rev1         True
bookinfo      bookinfo-valid         default      True
default       bookinfo               default      False
default       no-name-convention     default      True

  <p>This is a reference for the Core Extensions descriptor.</p>
  <p>The default location for the Core Extensions descriptor file is <code>${maven.projectBasedir}/.mvn/extensions.xml</code></p>
  ]]></description>

  <defaults>
    <default>
      <key>package</key>
      <value>org.apache.maven.cli.internal.extension.model</value>
    </default>
  </defaults>

  <classes>

```

////

## Required query parameters

When you declare a default value for non-path parameters (for now, we have only seen query parameters), then it is not required.

If you don't want to add a specific value but just make it optional, set the default as `None`.

But when you want to make a query parameter required, you can just not declare any default value:

```Python hl_lines="6-7"

    @Nonnull
    default DependencyResolverResult flatten(
            @Nonnull Session session, @Nonnull Project project, @Nonnull PathScope scope) {
        return flatten(DependencyResolverRequest.build(
                session, DependencyResolverRequest.RequestType.FLATTEN, project, scope));
    }

    @Nonnull

        }
    }

    default Object evaluateValue(final String scriptType, final String template, final Map<String, Object> paramMap) {
        if (StringUtil.isEmpty(template)) {
            return StringUtil.EMPTY;
        }

        return ComponentUtil.getScriptEngineFactory().getScriptEngine(scriptType).evaluate(template, paramMap);
    }

    default int getMaxSiteLength() {