Remove and forbid use of IndexWriter#isLocked

This commit removes and now forbids use of
org.apache.lucene.index.IndexWriter#isLocked as this method was
deprecated in LUCENE-6508. The deprecation is due to the fact that
checking if a lock is held before acquiring that lock is subject to a
time-of-check-to-time-of-use race condition. There were three uses of
IndexWriter#isLocked in the code base:
 - a logging statement in o.e.i.e.InternalEngine where we are already in
   an exceptional condition that the lock was held; in this case,
   logging whether or not the directory is locked is superfluous
 - in o.e.c.l.u.VersionsTests where we were verifying that a write lock
   is released upon closing an IndexWriter; in this case, the check is
   not needed as successfully closing an IndexWriter releases its
   write lock
 - in o.e.t.s.MockFSDirectoryService where we were verifying that a
   directory is not write-locked before (implicitly) trying to obtain
   such a write lock in org.apache.lucene.index.CheckIndex#<init> (this
   is the exact type of a situation that is subject to a race
   condition); in this case we can proceed by just (implicitly) trying
   to obtain the write lock and failing if we encounter a
   LockObtainFailedException

buildSrc/src/main/resources/forbidden/all-signatures.txt

@@ -45,6 +45,7 @@ org.apache.lucene.search.NumericRangeFilter
 org.apache.lucene.search.PrefixFilter
 org.apache.lucene.search.QueryWrapperFilter
 org.apache.lucene.search.join.BitDocIdSetCachingWrapperFilter
+org.apache.lucene.index.IndexWriter#isLocked(org.apache.lucene.store.Directory)
 
 java.nio.file.Paths @ Use org.elasticsearch.common.io.PathUtils.get() instead.
 java.nio.file.FileSystems#getDefault() @ use org.elasticsearch.common.io.PathUtils.getDefaultFileSystem() instead.

core/src/main/java/org/elasticsearch/index/engine/InternalEngine.java

@@ -959,8 +959,7 @@ public class InternalEngine extends Engine {
             });
             return new IndexWriter(store.directory(), iwc);
         } catch (LockObtainFailedException ex) {
-            boolean isLocked = IndexWriter.isLocked(store.directory());
-            logger.warn("Could not lock IndexWriter isLocked [{}]", ex, isLocked);
+            logger.warn("could not lock IndexWriter", ex);
             throw ex;
         }
     }

core/src/test/java/org/elasticsearch/common/lucene/uid/VersionsTests.java

@@ -56,7 +56,6 @@ import java.util.List;
 import java.util.Map;
 
 import static org.hamcrest.Matchers.equalTo;
-import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.notNullValue;
 import static org.hamcrest.Matchers.nullValue;
 
@@ -292,7 +291,6 @@ public class VersionsTests extends ESTestCase {
         }
 
         iw.close();
-        assertThat(IndexWriter.isLocked(iw.getDirectory()), is(false));
         ir.close();
         dir.close();
     }

test/framework/src/main/java/org/elasticsearch/test/store/MockFSDirectoryService.java

@@ -26,6 +26,7 @@ import org.apache.lucene.index.IndexWriter;
 import org.apache.lucene.store.BaseDirectoryWrapper;
 import org.apache.lucene.store.Directory;
 import org.apache.lucene.store.LockFactory;
+import org.apache.lucene.store.LockObtainFailedException;
 import org.apache.lucene.store.MockDirectoryWrapper;
 import org.apache.lucene.store.StoreRateLimiting;
 import org.apache.lucene.util.LuceneTestCase;
@@ -113,10 +114,6 @@ public class MockFSDirectoryService extends FsDirectoryService {
                 if (!Lucene.indexExists(dir)) {
                     return;
                 }
-                if (IndexWriter.isLocked(dir)) {
-                    ESTestCase.checkIndexFailed = true;
-                    throw new IllegalStateException("IndexWriter is still open on shard " + shardId);
-                }
                 try (CheckIndex checkIndex = new CheckIndex(dir)) {
                     BytesStreamOutput os = new BytesStreamOutput();
                     PrintStream out = new PrintStream(os, false, StandardCharsets.UTF_8.name());
@@ -134,6 +131,9 @@ public class MockFSDirectoryService extends FsDirectoryService {
                             logger.debug("check index [success]\n{}", new String(os.bytes().toBytes(), StandardCharsets.UTF_8));
                         }
                     }
+                } catch (LockObtainFailedException e) {
+                    ESTestCase.checkIndexFailed = true;
+                    throw new IllegalStateException("IndexWriter is still open on shard " + shardId, e);
                 }
             } catch (Exception e) {
                 logger.warn("failed to check index", e);