docs(samples): adds list training phrases sample (#336)

* docs(samples): adds list training phrases sample

* docs(samples): removed testing resources

* docs(samples): removed testing resources

* 🦉 Updates from OwlBot

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: 2 people

dialogflow-cx/snippets/src/main/java/dialogflow/cx/ListTrainingPhrases.java

@@ -0,0 +1,62 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dialogflow.cx;
+
+// [START dialogflow_list_training_phrases]
+import com.google.cloud.dialogflow.cx.v3.GetIntentRequest;
+import com.google.cloud.dialogflow.cx.v3.Intent;
+import com.google.cloud.dialogflow.cx.v3.IntentName;
+import com.google.cloud.dialogflow.cx.v3.IntentsClient;
+import java.io.IOException;
+import java.util.List;
+
+public class ListTrainingPhrases {
+  public static void main(String[] args) throws IOException {
+    // TODO(developer): Replace these variables before running the sample.
+    String projectId = "my-project-id";
+    String location = "location";
+    String agentId = "my-agent-id";
+    String intentId = "my-intent-id";
+
+    listTrainingPhrases(projectId, location, agentId, intentId);
+  }
+
+  // DialogFlow API List Training Phrases sample.
+  public static void listTrainingPhrases(
+      String projectId, String location, String agentId, String intentId) throws IOException {
+    try (IntentsClient client = IntentsClient.create()) {
+      // Set the intent name
+      IntentName name = IntentName.of(projectId, location, agentId, intentId);
+
+      // Compose the get-intent request
+      GetIntentRequest request = GetIntentRequest.newBuilder().setName(name.toString()).build();
+
+      // Make API request to get intent
+      Intent response = client.getIntent(request);
+
+      // Loop through the results
+      for (Intent.TrainingPhrase phrase : response.getTrainingPhrasesList()) {
+        System.out.println("***********************************************");
+        List<Intent.TrainingPhrase.Part> parts = phrase.getPartsList();
+        for (Intent.TrainingPhrase.Part part : parts) {
+          System.out.println(String.format("Training Phrase: %s", part.getText()));
+        }
+      }
+    }
+  }
+}
+// [END dialogflow_list_training_phrases]

dialogflow-cx/snippets/src/test/java/dialogflow/cx/ListTrainingPhrasesTest.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2021 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dialogflow.cx;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.PrintStream;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class ListTrainingPhrasesTest {
+  private static String PROJECT_ID = System.getenv().get("GOOGLE_CLOUD_PROJECT");
+  private static String LOCATION = "global";
+  private static String AGENT_ID = "b8d0e85d-0741-4e6d-a66a-3671184b7b93";
+  private static String INTENT_ID = "45974f75-9412-445a-9863-47bfdfa3d96d";
+
+  private ByteArrayOutputStream stdOut;
+
+  @Before
+  public void setUp() throws IOException {
+    stdOut = new ByteArrayOutputStream();
+    System.setOut(new PrintStream(stdOut));
+  }
+
+  @After
+  public void tearDown() throws IOException {
+    stdOut = null;
+    System.setOut(null);
+  }
+
+  @Test
+  public void testListTrainingPhrases() throws IOException {
+    ListTrainingPhrases.listTrainingPhrases(PROJECT_ID, LOCATION, AGENT_ID, INTENT_ID);
+    assertThat(stdOut.toString()).contains("green");
+  }
+}