Clean up "unused variable" warnings (#31876)

This change cleans up "unused variable" warnings. There are several cases were we 
most likely want to suppress the warnings (especially in the client documentation test
where the snippets contain many unused variables). In a lot of cases the unused
variables can just be deleted though.

Author: Christoph Büscher

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/CRUDDocumentationIT.java

@@ -114,6 +114,7 @@
  */
 public class CRUDDocumentationIT extends ESRestHighLevelClientTestCase {
 
+    @SuppressWarnings("unused")
     public void testIndex() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -278,6 +279,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testUpdate() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -546,6 +548,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testDelete() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -665,6 +668,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testBulk() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -767,6 +771,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testReindex() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -905,6 +910,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testReindexRethrottle() throws Exception {
         RestHighLevelClient client = highLevelClient();
         TaskId taskId = new TaskId("oTUltX4IQMOUUVeiohTt8A:124");
@@ -947,6 +953,7 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+    @SuppressWarnings("unused")
     public void testUpdateByQuery() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -1066,6 +1073,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testDeleteByQuery() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -1173,6 +1181,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testGet() throws Exception {
         RestHighLevelClient client = highLevelClient();
         {
@@ -1487,6 +1496,7 @@ public void afterBulk(long executionId, BulkRequest request, Throwable failure)
         }
     }
 
+    @SuppressWarnings("unused")
     public void testMultiGet() throws Exception {
         RestHighLevelClient client = highLevelClient();
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/ClusterClientDocumentationIT.java

@@ -192,6 +192,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testClusterGetSettings() throws IOException {
         RestHighLevelClient client = highLevelClient();
 
@@ -257,6 +258,7 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+    @SuppressWarnings("unused")
     public void testClusterHealth() throws IOException {
         RestHighLevelClient client = highLevelClient();
         client.indices().create(new CreateIndexRequest("index"), RequestOptions.DEFAULT);

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/IndicesClientDocumentationIT.java

@@ -706,6 +706,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testGetFieldMapping() throws IOException, InterruptedException {
         RestHighLevelClient client = highLevelClient();
 
@@ -891,6 +892,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testRefreshIndex() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -959,6 +961,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testFlushIndex() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1035,6 +1038,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testSyncedFlushIndex() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1308,6 +1312,7 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+    @SuppressWarnings("unused")
     public void testForceMergeIndex() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1381,6 +1386,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testClearCache() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1527,6 +1533,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testExistsAlias() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1590,6 +1597,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testUpdateAliases() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1915,6 +1923,7 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+    @SuppressWarnings("unused")
     public void testGetAlias() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -1985,6 +1994,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testIndexPutSettings() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -2315,6 +2325,7 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+    @SuppressWarnings("unused")
     public void testValidateQuery() throws IOException, InterruptedException {
         RestHighLevelClient client = highLevelClient();
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/IngestClientDocumentationIT.java

@@ -143,6 +143,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testGetPipeline() throws IOException {
         RestHighLevelClient client = highLevelClient();
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/SearchDocumentationIT.java

@@ -413,6 +413,7 @@ public void testSearchRequestSuggestions() throws IOException {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testSearchRequestHighlighting() throws IOException {
         RestHighLevelClient client = highLevelClient();
         {
@@ -831,6 +832,8 @@ public void onFailure(Exception e) {
         assertTrue(latch.await(30L, TimeUnit.SECONDS));
     }
 
+
+    @SuppressWarnings("unused")
     public void testMultiSearchTemplateWithInlineScript() throws Exception {
         indexSearchTestData();
         RestHighLevelClient client = highLevelClient();

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/SnapshotClientDocumentationIT.java

@@ -577,6 +577,7 @@ public void onFailure(Exception exception) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testSnapshotGetSnapshots() throws IOException {
         RestHighLevelClient client = highLevelClient();
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/StoredScriptsDocumentationIT.java

@@ -66,6 +66,7 @@
  */
 public class StoredScriptsDocumentationIT extends ESRestHighLevelClientTestCase {
 
+    @SuppressWarnings("unused")
     public void testGetStoredScript() throws Exception {
         RestHighLevelClient client = highLevelClient();
 
@@ -128,6 +129,7 @@ public void onFailure(Exception e) {
 
     }
 
+    @SuppressWarnings("unused")
     public void testDeleteStoredScript() throws Exception {
         RestHighLevelClient client = highLevelClient();
 

client/rest-high-level/src/test/java/org/elasticsearch/client/documentation/TasksClientDocumentationIT.java

@@ -66,6 +66,7 @@
  */
 public class TasksClientDocumentationIT extends ESRestHighLevelClientTestCase {
 
+    @SuppressWarnings("unused")
     public void testListTasks() throws IOException {
         RestHighLevelClient client = highLevelClient();
         {
@@ -149,6 +150,7 @@ public void onFailure(Exception e) {
         }
     }
 
+    @SuppressWarnings("unused")
     public void testCancelTasks() throws IOException {
         RestHighLevelClient client = highLevelClient();
         {

libs/grok/src/main/java/org/elasticsearch/grok/Grok.java

@@ -35,12 +35,12 @@
 import java.io.UncheckedIOException;
 import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
-import java.util.Collections;
 
 public final class Grok {
 
@@ -184,6 +184,7 @@ public String toRegex(String grokPattern) {
             String namedPatternRef = groupMatch(NAME_GROUP, region, grokPattern);
             String subName = groupMatch(SUBNAME_GROUP, region, grokPattern);
             // TODO(tal): Support definitions
+            @SuppressWarnings("unused")
             String definition = groupMatch(DEFINITION_GROUP, region, grokPattern);
             String patternName = groupMatch(PATTERN_GROUP, region, grokPattern);
 

libs/grok/src/test/java/org/elasticsearch/grok/GrokTests.java

@@ -262,8 +262,6 @@ public void testCircularReference() {
     }
 
     public void testBooleanCaptures() {
-        Map<String, String> bank = new HashMap<>();
-
         String pattern = "%{WORD:name}=%{WORD:status:boolean}";
         Grok g = new Grok(basePatterns, pattern);