refactor(samples): load clustered table (#622)

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

@@ -33,9 +33,10 @@
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 
+// Sample to load clustered table.
 public class LoadTableClustered {
 
-  public static void runLoadTableClustered() throws Exception {
+  public static void runLoadTableClustered() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
@@ -54,8 +55,7 @@ public static void loadTableClustered(
       String tableName,
       String sourceUri,
       Schema schema,
-      List<String> clusteringFields)
-      throws Exception {
+      List<String> clusteringFields) {
     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.
@@ -80,19 +80,16 @@ public static void loadTableClustered(
 
       // Load data from a GCS parquet file into the table
       // Blocks until this load table job completes its execution, either failing or succeeding.
-      Job completedJob = loadJob.waitFor();
+      Job job = loadJob.waitFor();
 
       // Check for errors
-      if (completedJob == null) {
-        throw new Exception("Job not executed since it no longer exists.");
-      } else if (completedJob.getStatus().getError() != null) {
-        // You can also look at queryJob.getStatus().getExecutionErrors() for all
-        // errors, not just the latest one.
-        throw new Exception(
-            "BigQuery was unable to load into the table due to an error: \n"
-                + loadJob.getStatus().getError());
+      if (job.isDone() && job.getStatus().getError() == null) {
+        System.out.println("Data successfully loaded into clustered table during load job");
+      } else {
+        System.out.println(
+            "BigQuery was unable to load into the table due to an error:"
+                + job.getStatus().getError());
       }
-      System.out.println("Data successfully loaded into clustered table during load job");
     } catch (BigQueryException | InterruptedException e) {
       System.out.println("Data not loaded into clustered table during load job \n" + e.toString());
     }

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

@@ -25,21 +25,26 @@
 import com.google.common.collect.ImmutableList;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.util.UUID;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
 public class LoadTableClusteredIT {
+
+  private String tableName;
   private ByteArrayOutputStream bout;
   private PrintStream out;
 
-  private static final String BIGQUERY_DATASET_NAME = System.getenv("BIGQUERY_DATASET_NAME");
+  private static final String BIGQUERY_DATASET_NAME = requireEnvVar("BIGQUERY_DATASET_NAME");
 
-  private static void requireEnvVar(String varName) {
+  private static String requireEnvVar(String varName) {
+    String value = System.getenv(varName);
     assertNotNull(
         "Environment variable " + varName + " is required to perform these tests.",
         System.getenv(varName));
+    return value;
   }
 
   @BeforeClass
@@ -49,22 +54,22 @@ public static void checkRequirements() {
 
   @Before
   public void setUp() {
+    tableName = "LOAD_CLUSTERED_TABLE_TEST_" + UUID.randomUUID().toString().substring(0, 8);
     bout = new ByteArrayOutputStream();
     out = new PrintStream(bout);
     System.setOut(out);
   }
 
   @After
   public void tearDown() {
+    // Clean up
+    DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, tableName);
     System.setOut(null);
   }
 
   @Test
-  public void loadTableClustered() throws Exception {
+  public void testLoadTableClustered() {
     String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states-by-date-no-header.csv";
-
-    String tableName = "LOAD_CLUSTERED_TABLE_TEST";
-
     Schema schema =
         Schema.of(
             Field.of("name", StandardSQLTypeName.STRING),
@@ -73,11 +78,7 @@ public void loadTableClustered() throws Exception {
 
     LoadTableClustered.loadTableClustered(
         BIGQUERY_DATASET_NAME, tableName, sourceUri, schema, ImmutableList.of("name", "post_abbr"));
-
     assertThat(bout.toString())
         .contains("Data successfully loaded into clustered table during load job");
-
-    // Clean up
-    DeleteTable.deleteTable(BIGQUERY_DATASET_NAME, tableName);
   }
 }