docs(samples): add cancel job (#487)

samples/snippets/src/main/java/com/example/bigquery/CancelJob.java

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+/*
+ * Copyright 2020 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 com.example.bigquery;
+
+// [START bigquery_cancel_job]
+import com.google.cloud.bigquery.BigQuery;
+import com.google.cloud.bigquery.BigQueryException;
+import com.google.cloud.bigquery.BigQueryOptions;
+import com.google.cloud.bigquery.Job;
+import com.google.cloud.bigquery.JobId;
+import com.google.cloud.bigquery.JobInfo;
+import com.google.cloud.bigquery.QueryJobConfiguration;
+import java.util.UUID;
+
+// Sample to cancel a job
+public class CancelJob {
+
+  public static void runCancelJob() {
+    // TODO(developer): Replace these variables before running the sample.
+    String query = "SELECT country_name from `bigquery-public-data.utility_us.country_code_iso`";
+    cancelJob(query);
+  }
+
+  public static void cancelJob(String query) {
+    try {
+      // Initialize client that will be used to send requests. This client only needs to be created
+      // once, and can be reused for multiple requests.
+      BigQuery bigquery = BigQueryOptions.getDefaultInstance().getService();
+
+      // Specify a job configuration to set optional job resource properties.
+      QueryJobConfiguration queryConfig = QueryJobConfiguration.newBuilder(query).build();
+
+      // The location and job name are optional,
+      // if both are not specified then client will auto-create.
+      String jobName = "jobId_" + UUID.randomUUID().toString();
+      JobId jobId = JobId.newBuilder().setLocation("us").setJob(jobName).build();
+
+      // Create a job with job ID
+      bigquery.create(JobInfo.of(jobId, queryConfig));
+
+      // Get a job that was just created
+      Job job = bigquery.getJob(jobId);
+      if (job.cancel()) {
+        System.out.println("Job canceled successfully");
+      } else {
+        System.out.println("Job was not canceled");
+      }
+    } catch (BigQueryException e) {
+      System.out.println("Job was not canceled.\n" + e.toString());
+    }
+  }
+}
+// [END bigquery_cancel_job]

samples/snippets/src/test/java/com/example/bigquery/CancelJobIT.java

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+/*
+ * Copyright 2020 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 com.example.bigquery;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class CancelJobIT {
+
+  private ByteArrayOutputStream bout;
+  private PrintStream out;
+
+  @Before
+  public void setUp() {
+    bout = new ByteArrayOutputStream();
+    out = new PrintStream(bout);
+    System.setOut(out);
+  }
+
+  @After
+  public void tearDown() {
+    System.setOut(null);
+  }
+
+  @Test
+  public void testCreateJob() {
+    String query = "SELECT country_name from `bigquery-public-data.utility_us.country_code_iso`";
+
+    CancelJob.cancelJob(query);
+    assertThat(bout.toString()).contains("Job canceled successfully");
+  }
+}