Add instructions for Java

app/components/ClientSampleCode.tsx

@@ -39,7 +39,7 @@ export function ClientSampleCode({
   clientSecret?: string
   listTopics?: boolean
   topics?: string[]
-  language: 'py' | 'mjs' | 'cjs' | 'c' | 'cs'
+  language: 'py' | 'mjs' | 'cjs' | 'c' | 'cs' | 'java'
 }) {
   const domain = useDomain()
 
@@ -511,5 +511,67 @@ export function ClientSampleCode({
           project.
         </>
       )
+    case 'java':
+      return (
+        <>
+          <p>
+            The following instructions are for the official Kafka command line
+            tools which use Java and come with either{' '}
+            <a
+              rel="external"
+              href="https://kafka.apache.org/documentation/#quickstart"
+            >
+              Apache Kafka
+            </a>{' '}
+            or{' '}
+            <a
+              rel="external"
+              href="https://docs.confluent.io/kafka/operations-tools/kafka-tools.html"
+            >
+              Confluent
+            </a>
+            . However, they should work with most Java code that uses the
+            official Apache Kafka client libraries.
+          </p>
+          Save the configuration below to a file called{' '}
+          <code>example.properties</code>:
+          <Highlight
+            language="properties"
+            filename="example.properties"
+            code={dedent(String.raw`
+              security.protocol = SASL_SSL
+              sasl.mechanism = OAUTHBEARER
+              sasl.login.callback.handler.class = org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginCallbackHandler
+              sasl.oauthbearer.token.endpoint.url = https://auth.${
+                domain ?? 'gcn.nasa.gov'
+              }/oauth2/token
+              sasl.jaas.config = org.apache.kafka.common.security.oauthbearer.OAuthBearerLoginModule required \
+                clientId="${clientId}" \
+                clientSecret="${clientSecret}";
+              # Warning: don't share the client secret with others.
+            `)}
+          />
+          <p>Next, open a terminal.</p>
+          {listTopics && (
+            <>
+              Run the following command to list available Kafka topics.
+              <Highlight
+                language="sh"
+                code={`kafka-topics.sh --bootstrap-server kafka.${
+                  domain ?? 'gcn.nasa.gov'
+                }:9092 --command-config example.properties --list`}
+              />
+            </>
+          )}
+          Run the following command to consume Kafka records and print them to
+          the console.
+          <Highlight
+            language="sh"
+            code={`kafka-console-consumer.sh --bootstrap-server kafka.${
+              domain ?? 'gcn.nasa.gov'
+            }:9092 --consumer.config example.properties${topics.map((topic) => ` ${topic}`).join('')}`}
+          />
+        </>
+      )
   }
 }

app/components/Highlight.tsx

@@ -7,9 +7,12 @@
  */
 import { Icon, Tooltip } from '@trussworks/react-uswds'
 import hljs from 'highlight.js/lib/common'
+import properties from 'highlight.js/lib/languages/properties'
 import { useState } from 'react'
 import CopyToClipboard from 'react-copy-to-clipboard'
 
+hljs.registerLanguage('properties', properties)
+
 export function Highlight({
   code,
   language,

app/routes/_gcn.docs.client._index.mdx

@@ -39,6 +39,10 @@ For C#, use the [Confluent.Kafka](https://www.nuget.org/packages/Confluent.Kafka
 
 <ClientSampleCode language="cs" />
 
+## Java
+
+<ClientSampleCode language="java" />
+
 ## Known Issues
 
 ### confluent-kafka-python

app/routes/_gcn.docs.tsx

@@ -131,6 +131,9 @@ export default function () {
                     <Link key="c-1" to="client#c-1">
                       C#
                     </Link>,
+                    <Link key="java" to="client#java">
+                      Java
+                    </Link>,
                     <NavLink key="code-samples" to="client/samples">
                       Sample Code
                     </NavLink>,

app/routes/_gcn.quickstart.code.tsx

@@ -83,6 +83,12 @@ export default function () {
             language="cs"
           />
         </Tab>
+        <Tab label="Java">
+          <ClientSampleCode
+            {...{ clientName, clientId, clientSecret, topics, listTopics }}
+            language="java"
+          />
+        </Tab>
       </Tabs>
       <Form method="GET" action="../alerts">
         <input type="hidden" name="clientId" value={clientId} />

package.json

@@ -118,6 +118,7 @@
     "jest-environment-jsdom": "^29.7.0",
     "jest-transform-stub": "^2.0.0",
     "lint-staged": "^15.2.2",
+    "lowlight": "^3.0.0",
     "nasawds": "^4.0.2-beta.1",
     "npm-run-all": "^4.1.5",
     "oidc-provider": "^8.4.3",

remix.config.js

@@ -1,3 +1,5 @@
+import properties from 'highlight.js/lib/languages/properties'
+import { common } from 'lowlight'
 import rehypeAutolinkHeadings from 'rehype-autolink-headings'
 import rehypeClassNames from 'rehype-class-names'
 import rehypeExternalLinks from 'rehype-external-links'
@@ -38,7 +40,7 @@ const esmOnlyModules = [
 export default {
   mdx: {
     rehypePlugins: [
-      rehypeHighlight,
+      (options) => rehypeHighlight({ ...common, properties }),
       rehypeSlug,
       (options) =>
         rehypeExternalLinks({