docs(samples): Convert tightly coupled local variable inside of method into method arguments (#386)

As the previous PR #382  and #379.
I find several other samples that have the tendencies of including tightly coupled 
variable for each of specific method. Hence I think it will be better to pass it as an argument instead of simply using local variable inside of the method.

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- [x] Code coverage does not decrease (if any source code was changed)
- [x] Appropriate docs were updated (if necessary)

Fixes #387  ☕️

Author: irvifa

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

@@ -32,6 +32,8 @@
 import com.google.cloud.bigquery.Schema;
 import com.google.cloud.bigquery.TableId;
 import com.google.common.collect.ImmutableList;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.UUID;
 
 public class AddColumnLoadAppend {
@@ -41,31 +43,35 @@ public static void runAddColumnLoadAppend() throws Exception {
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
     String sourceUri = "/path/to/file.csv";
-    addColumnLoadAppend(datasetName, tableName, sourceUri);
+    // Add a new column to a BigQuery table while appending rows via a load job.
+    // 'REQUIRED' fields cannot  be added to an existing schema, so the additional column must be
+    // 'NULLABLE'.
+    Schema schema =
+      Schema.of(
+        Field.newBuilder("name", LegacySQLTypeName.STRING)
+                .setMode(Field.Mode.REQUIRED)
+                .build());
+
+    List<Field> fields = schema.getFields();
+    // Adding below additional column during the load job
+    Field newField = Field.newBuilder("post_abbr", LegacySQLTypeName.STRING)
+            .setMode(Field.Mode.NULLABLE)
+            .build();
+    List<Field> newFields = new ArrayList<>(fields);
+    newFields.add(newField);
+    Schema newSchema = Schema.of(newFields);
+    addColumnLoadAppend(datasetName, tableName, sourceUri, newSchema);
   }
 
-  public static void addColumnLoadAppend(String datasetName, String tableName, String sourceUri)
-      throws Exception {
+  public static void addColumnLoadAppend(String datasetName, String tableName,
+     String sourceUri, Schema newSchema) throws Exception {
     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();
 
       TableId tableId = TableId.of(datasetName, tableName);
 
-      // Add a new column to a BigQuery table while appending rows via a load job.
-      // 'REQUIRED' fields cannot  be added to an existing schema, so the additional column must be
-      // 'NULLABLE'.
-      Schema newSchema =
-          Schema.of(
-              Field.newBuilder("name", LegacySQLTypeName.STRING)
-                  .setMode(Field.Mode.REQUIRED)
-                  .build(),
-              // Adding below additional column during the load job
-              Field.newBuilder("post_abbr", LegacySQLTypeName.STRING)
-                  .setMode(Field.Mode.NULLABLE)
-                  .build());
-
       LoadJobConfiguration loadJobConfig =
           LoadJobConfiguration.builder(tableId, sourceUri)
               .setFormatOptions(FormatOptions.csv())

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

@@ -32,17 +32,18 @@ public class LoadParquet {
   public static void runLoadParquet() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
-    loadParquet(datasetName);
+    String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
+    String tableName = "us_states";
+    loadParquet(datasetName, tableName, sourceUri);
   }
 
-  public static void loadParquet(String datasetName) {
+  public static void loadParquet(String datasetName, String tableName, String sourceUri) {
     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();
 
-      String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
-      TableId tableId = TableId.of(datasetName, "us_states");
+      TableId tableId = TableId.of(datasetName, tableName);
 
       LoadJobConfiguration configuration =
           LoadJobConfiguration.builder(tableId, sourceUri)

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

@@ -34,10 +34,13 @@ public class LoadParquetReplaceTable {
   public static void runLoadParquetReplaceTable() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
-    loadParquetReplaceTable(datasetName);
+    String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
+    String tableName = "us_states";
+    loadParquetReplaceTable(datasetName, tableName, sourceUri);
   }
 
-  public static void loadParquetReplaceTable(String datasetName) {
+  public static void loadParquetReplaceTable(String datasetName, String tableName,
+     String sourceUri) {
     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.
@@ -46,8 +49,7 @@ public static void loadParquetReplaceTable(String datasetName) {
       // Imports a GCS file into a table and overwrites table data if table already exists.
       // This sample loads CSV file at:
       // https://storage.googleapis.com/cloud-samples-data/bigquery/us-states/us-states.csv
-      String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
-      TableId tableId = TableId.of(datasetName, "us_states");
+      TableId tableId = TableId.of(datasetName, tableName);
 
       // For more information on LoadJobConfiguration see:
       // https://googleapis.dev/java/google-cloud-clients/latest/com/google/cloud/bigquery/LoadJobConfiguration.Builder.html

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

@@ -34,10 +34,16 @@ public static void runTableInsertRows() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
-    tableInsertRows(datasetName, tableName);
+    // Create a row to insert
+    Map<String, Object> rowContent = new HashMap<>();
+    rowContent.put("booleanField", true);
+    rowContent.put("numericField", "3.14");
+
+    tableInsertRows(datasetName, tableName, rowContent);
   }
 
-  public static void tableInsertRows(String datasetName, String tableName) {
+  public static void tableInsertRows(String datasetName, String tableName,
+     Map<String, Object> rowContent) {
     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.
@@ -46,11 +52,6 @@ public static void tableInsertRows(String datasetName, String tableName) {
       // Get table
       TableId tableId = TableId.of(datasetName, tableName);
 
-      // Create a row to insert
-      Map<String, Object> rowContent = new HashMap<>();
-      rowContent.put("booleanField", true);
-      rowContent.put("numericField", "3.14");
-
       // Inserts rowContent into datasetName:tableId.
       InsertAllResponse response =
           bigquery.insertAll(InsertAllRequest.newBuilder(tableId).addRow(rowContent).build());

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

@@ -31,22 +31,22 @@ public class UpdateDatasetAccess {
   public static void runUpdateDatasetAccess() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
-    updateDatasetAccess(datasetName);
+    // Create a new ACL granting the READER role to "sample.bigquery.dev@gmail.com"
+    // For more information on the types of ACLs available see:
+    // https://cloud.google.com/storage/docs/access-control/lists
+    Acl newEntry = Acl.of(new User("sample.bigquery.dev@gmail.com"), Role.READER);
+
+    updateDatasetAccess(datasetName, newEntry);
   }
 
-  public static void updateDatasetAccess(String datasetName) {
+  public static void updateDatasetAccess(String datasetName, Acl newEntry) {
     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();
 
       Dataset dataset = bigquery.getDataset(datasetName);
 
-      // Create a new ACL granting the READER role to "sample.bigquery.dev@gmail.com"
-      // For more information on the types of ACLs available see:
-      // https://cloud.google.com/storage/docs/access-control/lists
-      Acl newEntry = Acl.of(new User("sample.bigquery.dev@gmail.com"), Role.READER);
-
       // Get a copy of the ACLs list from the dataset and append the new entry
       ArrayList<Acl> acls = new ArrayList<>(dataset.getAcl());
       acls.add(newEntry);

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

@@ -28,18 +28,17 @@ public class UpdateDatasetExpiration {
   public static void runUpdateDatasetExpiration() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
-    updateDatasetExpiration(datasetName);
+    // Update dataset expiration to one day
+    Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
+    updateDatasetExpiration(datasetName, newExpiration);
   }
 
-  public static void updateDatasetExpiration(String datasetName) {
+  public static void updateDatasetExpiration(String datasetName, Long newExpiration) {
     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();
 
-      // Update dataset expiration to one day
-      Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
-
       Dataset dataset = bigquery.getDataset(datasetName);
       bigquery.update(dataset.toBuilder().setDefaultTableLifetime(newExpiration).build());
       System.out.println("Dataset description updated successfully to " + newExpiration);

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

@@ -29,18 +29,18 @@ public static void runUpdateTableExpiration() {
     // TODO(developer): Replace these variables before running the sample.
     String datasetName = "MY_DATASET_NAME";
     String tableName = "MY_TABLE_NAME";
-    updateTableExpiration(datasetName, tableName);
+    // Update table expiration to one day.
+    Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
+    updateTableExpiration(datasetName, tableName, newExpiration);
   }
 
-  public static void updateTableExpiration(String datasetName, String tableName) {
+  public static void updateTableExpiration(String datasetName, String tableName,
+     Long newExpiration) {
     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();
 
-      // Update table expiration to one day
-      Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
-
       Table table = bigquery.getTable(datasetName, tableName);
       bigquery.update(table.toBuilder().setExpirationTime(newExpiration).build());
 

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

@@ -24,6 +24,8 @@
 import com.google.cloud.bigquery.Schema;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.util.ArrayList;
+import java.util.List;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -71,7 +73,16 @@ public void testAddColumnLoadAppend() throws Exception {
 
     CreateTable.createTable(BIGQUERY_DATASET_NAME, tableName, originalSchema);
 
-    AddColumnLoadAppend.addColumnLoadAppend(BIGQUERY_DATASET_NAME, tableName, sourceUri);
+    List<Field> fields = originalSchema.getFields();
+    // Adding below additional column during the load job
+    Field newField = Field.newBuilder("post_abbr", LegacySQLTypeName.STRING)
+            .setMode(Field.Mode.NULLABLE)
+            .build();
+    List<Field> newFields = new ArrayList<>(fields);
+    newFields.add(newField);
+    Schema newSchema = Schema.of(newFields);
+
+    AddColumnLoadAppend.addColumnLoadAppend(BIGQUERY_DATASET_NAME, tableName, sourceUri, newSchema);
 
     assertThat(bout.toString()).contains("Column successfully added during load append job");
 

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

@@ -57,7 +57,9 @@ public void tearDown() {
 
   @Test
   public void loadParquet() {
-    LoadParquet.loadParquet(BIGQUERY_DATASET_NAME);
+    String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
+    String tableName = "us_states";
+    LoadParquet.loadParquet(BIGQUERY_DATASET_NAME, tableName, sourceUri);
     assertThat(bout.toString()).contains("GCS parquet loaded successfully.");
   }
 }

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

@@ -57,7 +57,9 @@ public void tearDown() {
 
   @Test
   public void testLoadParquetReplaceTable() {
-    LoadParquetReplaceTable.loadParquetReplaceTable(BIGQUERY_DATASET_NAME);
+    String sourceUri = "gs://cloud-samples-data/bigquery/us-states/us-states.parquet";
+    String tableName = "us_states";
+    LoadParquetReplaceTable.loadParquetReplaceTable(BIGQUERY_DATASET_NAME, tableName, sourceUri);
     assertThat(bout.toString()).contains("GCS parquet overwrote existing table successfully.");
   }
 }

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

@@ -24,6 +24,8 @@
 import com.google.cloud.bigquery.Schema;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.util.HashMap;
+import java.util.Map;
 import java.util.UUID;
 import org.junit.After;
 import org.junit.Before;
@@ -70,8 +72,13 @@ public void testTableInsertRows() {
     // Create table in dataset for testing
     CreateTable.createTable(BIGQUERY_DATASET_NAME, tableName, schema);
 
+    // Create a row to insert
+    Map<String, Object> rowContent = new HashMap<>();
+    rowContent.put("booleanField", true);
+    rowContent.put("numericField", "3.14");
+
     // Testing
-    TableInsertRows.tableInsertRows(BIGQUERY_DATASET_NAME, tableName);
+    TableInsertRows.tableInsertRows(BIGQUERY_DATASET_NAME, tableName, rowContent);
     assertThat(bout.toString()).contains("Rows successfully inserted into table");
 
     // Clean up

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

@@ -19,6 +19,9 @@
 import static com.google.common.truth.Truth.assertThat;
 import static junit.framework.TestCase.assertNotNull;
 
+import com.google.cloud.bigquery.Acl;
+import com.google.cloud.bigquery.Acl.Role;
+import com.google.cloud.bigquery.Acl.User;
 import com.google.cloud.bigquery.testing.RemoteBigQueryHelper;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
@@ -62,8 +65,9 @@ public void updateDatasetAccess() {
     // Create a dataset in order to modify its ACL
     CreateDataset.createDataset(generatedDatasetName);
 
+    Acl newEntry = Acl.of(new User("sample.bigquery.dev@gmail.com"), Role.READER);
     // Modify dataset's ACL
-    UpdateDatasetAccess.updateDatasetAccess(generatedDatasetName);
+    UpdateDatasetAccess.updateDatasetAccess(generatedDatasetName, newEntry);
     assertThat(bout.toString()).contains("Dataset Access Control updated successfully");
 
     // Clean up

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

@@ -22,6 +22,7 @@
 import com.google.cloud.bigquery.testing.RemoteBigQueryHelper;
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.util.concurrent.TimeUnit;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -62,8 +63,9 @@ public void updateDatasetExpiration() {
     // Create a dataset in order to modify its expiration
     CreateDataset.createDataset(generatedDatasetName);
 
+    Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
     // Modify dataset's expiration
-    UpdateDatasetExpiration.updateDatasetExpiration(generatedDatasetName);
+    UpdateDatasetExpiration.updateDatasetExpiration(generatedDatasetName, newExpiration);
     assertThat(bout.toString()).contains("Dataset description updated successfully");
 
     // Clean up

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

@@ -21,6 +21,7 @@
 
 import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
+import java.util.concurrent.TimeUnit;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.BeforeClass;
@@ -59,7 +60,8 @@ public void tearDown() {
   public void updateTableExpiration() {
     String tableName = "update_expiration_table";
     CreateTable.createTable(BIGQUERY_DATASET_NAME, tableName, null);
-    UpdateTableExpiration.updateTableExpiration(BIGQUERY_DATASET_NAME, tableName);
+    Long newExpiration = TimeUnit.MILLISECONDS.convert(1, TimeUnit.DAYS);
+    UpdateTableExpiration.updateTableExpiration(BIGQUERY_DATASET_NAME, tableName, newExpiration);
     assertThat(bout.toString()).contains("Table expiration updated successfully");
 
     // Clean up