Simplify a test case in Java ReadOnlyTest (#7608)

Summary:
The original test nests a lot of `try` blocks. This PR flattens these blocks into independent blocks, so that each `try` block closes the DB before opening the next DB instance.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7608

Test Plan: watch the existing java tests to pass

Reviewed By: zhichao-cao

Differential Revision: D24611621

Pulled By: cheng-chang

fbshipit-source-id: d486c5d37ac25d4b860d739ef2cdd58e6064d42d

java/src/test/java/org/rocksdb/ReadOnlyTest.java

@@ -31,115 +31,60 @@ public class ReadOnlyTest {
          final RocksDB db = RocksDB.open(options,
              dbFolder.getRoot().getAbsolutePath())) {
       db.put("key".getBytes(), "value".getBytes());
-      try (final RocksDB db2 = RocksDB.openReadOnly(
+    }
-          dbFolder.getRoot().getAbsolutePath())) {
+    try (final RocksDB db = RocksDB.openReadOnly(dbFolder.getRoot().getAbsolutePath())) {
-        assertThat("value").
+      assertThat("value").isEqualTo(new String(db.get("key".getBytes())));
-            isEqualTo(new String(db2.get("key".getBytes())));
-      }
     }
 
     try (final ColumnFamilyOptions cfOpts = new ColumnFamilyOptions()) {
       final List<ColumnFamilyDescriptor> cfDescriptors = new ArrayList<>();
-      cfDescriptors.add(new ColumnFamilyDescriptor(
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY, cfOpts));
-          RocksDB.DEFAULT_COLUMN_FAMILY, cfOpts));
-
       final List<ColumnFamilyHandle> columnFamilyHandleList = new ArrayList<>();
-      try (final RocksDB db = RocksDB.open(dbFolder.getRoot().getAbsolutePath(),
+      try (final RocksDB db = RocksDB.open(
-          cfDescriptors, columnFamilyHandleList)) {
+               dbFolder.getRoot().getAbsolutePath(), cfDescriptors, columnFamilyHandleList)) {
-        try (final ColumnFamilyOptions newCfOpts = new ColumnFamilyOptions();
+        columnFamilyHandleList.add(
-             final ColumnFamilyOptions newCf2Opts = new ColumnFamilyOptions()
+            db.createColumnFamily(new ColumnFamilyDescriptor("new_cf".getBytes(), cfOpts)));
-        ) {
+        columnFamilyHandleList.add(
-          columnFamilyHandleList.add(db.createColumnFamily(
+            db.createColumnFamily(new ColumnFamilyDescriptor("new_cf2".getBytes(), cfOpts)));
-              new ColumnFamilyDescriptor("new_cf".getBytes(), newCfOpts)));
+        db.put(columnFamilyHandleList.get(2), "key2".getBytes(), "value2".getBytes());
-          columnFamilyHandleList.add(db.createColumnFamily(
+      }
-              new ColumnFamilyDescriptor("new_cf2".getBytes(), newCf2Opts)));
-          db.put(columnFamilyHandleList.get(2), "key2".getBytes(),
-              "value2".getBytes());
 
-          final List<ColumnFamilyHandle> readOnlyColumnFamilyHandleList =
+      columnFamilyHandleList.clear();
-              new ArrayList<>();
+      try (final RocksDB db = RocksDB.openReadOnly(
-          try (final RocksDB db2 = RocksDB.openReadOnly(
+               dbFolder.getRoot().getAbsolutePath(), cfDescriptors, columnFamilyHandleList)) {
-              dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
+        assertThat(db.get("key2".getBytes())).isNull();
-              readOnlyColumnFamilyHandleList)) {
+        assertThat(db.get(columnFamilyHandleList.get(0), "key2".getBytes())).isNull();
-            try (final ColumnFamilyOptions newCfOpts2 =
+      }
-                     new ColumnFamilyOptions();
-                 final ColumnFamilyOptions newCf2Opts2 =
-                     new ColumnFamilyOptions()
-            ) {
-              assertThat(db2.get("key2".getBytes())).isNull();
-              assertThat(db2.get(readOnlyColumnFamilyHandleList.get(0),
-                  "key2".getBytes())).
-                  isNull();
-              cfDescriptors.clear();
-              cfDescriptors.add(
-                  new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY,
-                      newCfOpts2));
-              cfDescriptors.add(new ColumnFamilyDescriptor("new_cf2".getBytes(),
-                      newCf2Opts2));
 
-              final List<ColumnFamilyHandle> readOnlyColumnFamilyHandleList2
+      cfDescriptors.clear();
-                  = new ArrayList<>();
+      cfDescriptors.add(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY, cfOpts));
-              try (final RocksDB db3 = RocksDB.openReadOnly(
+      cfDescriptors.add(new ColumnFamilyDescriptor("new_cf2".getBytes(), cfOpts));
-                  dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
+      columnFamilyHandleList.clear();
-                  readOnlyColumnFamilyHandleList2)) {
+      try (final RocksDB db = RocksDB.openReadOnly(
-                try {
+               dbFolder.getRoot().getAbsolutePath(), cfDescriptors, columnFamilyHandleList)) {
-                  assertThat(new String(db3.get(
+        assertThat(new String(db.get(columnFamilyHandleList.get(1), "key2".getBytes())))
-                      readOnlyColumnFamilyHandleList2.get(1),
+            .isEqualTo("value2");
-                      "key2".getBytes()))).isEqualTo("value2");
-                } finally {
-                  for (final ColumnFamilyHandle columnFamilyHandle :
-                      readOnlyColumnFamilyHandleList2) {
-                    columnFamilyHandle.close();
-                  }
-                }
-              }
-            } finally {
-              for (final ColumnFamilyHandle columnFamilyHandle :
-                  readOnlyColumnFamilyHandleList) {
-                columnFamilyHandle.close();
-              }
-            }
-          }
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              columnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
 
   @Test(expected = RocksDBException.class)
   public void failToWriteInReadOnly() throws RocksDBException {
-    try (final Options options = new Options()
+    try (final Options options = new Options().setCreateIfMissing(true)) {
-        .setCreateIfMissing(true)) {
+      try (final RocksDB db = RocksDB.open(options, dbFolder.getRoot().getAbsolutePath())) {
-
+        // no-op
-      try (final RocksDB db = RocksDB.open(options,
-          dbFolder.getRoot().getAbsolutePath())) {
-        //no-op
       }
     }
 
     try (final ColumnFamilyOptions cfOpts = new ColumnFamilyOptions()) {
-      final List<ColumnFamilyDescriptor> cfDescriptors = Arrays.asList(
+      final List<ColumnFamilyDescriptor> cfDescriptors =
-          new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY, cfOpts)
+          Arrays.asList(new ColumnFamilyDescriptor(RocksDB.DEFAULT_COLUMN_FAMILY, cfOpts));
-      );
 
-      final List<ColumnFamilyHandle> readOnlyColumnFamilyHandleList =
+      final List<ColumnFamilyHandle> readOnlyColumnFamilyHandleList = new ArrayList<>();
-          new ArrayList<>();
+      try (final RocksDB rDb = RocksDB.openReadOnly(dbFolder.getRoot().getAbsolutePath(),
-      try (final RocksDB rDb = RocksDB.openReadOnly(
+               cfDescriptors, readOnlyColumnFamilyHandleList)) {
-          dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
+        // test that put fails in readonly mode
-          readOnlyColumnFamilyHandleList)) {
+        rDb.put("key".getBytes(), "value".getBytes());
-        try {
-          // test that put fails in readonly mode
-          rDb.put("key".getBytes(), "value".getBytes());
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -161,15 +106,7 @@ public class ReadOnlyTest {
       try (final RocksDB rDb = RocksDB.openReadOnly(
           dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
           readOnlyColumnFamilyHandleList)) {
-        try {
+        rDb.put(readOnlyColumnFamilyHandleList.get(0), "key".getBytes(), "value".getBytes());
-          rDb.put(readOnlyColumnFamilyHandleList.get(0),
-              "key".getBytes(), "value".getBytes());
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -193,14 +130,7 @@ public class ReadOnlyTest {
       try (final RocksDB rDb = RocksDB.openReadOnly(
           dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
           readOnlyColumnFamilyHandleList)) {
-        try {
+        rDb.delete("key".getBytes());
-          rDb.delete("key".getBytes());
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -223,15 +153,8 @@ public class ReadOnlyTest {
       try (final RocksDB rDb = RocksDB.openReadOnly(
           dbFolder.getRoot().getAbsolutePath(), cfDescriptors,
           readOnlyColumnFamilyHandleList)) {
-        try {
           rDb.delete(readOnlyColumnFamilyHandleList.get(0),
               "key".getBytes());
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -256,15 +179,8 @@ public class ReadOnlyTest {
           readOnlyColumnFamilyHandleList);
            final WriteBatch wb = new WriteBatch();
            final WriteOptions wOpts = new WriteOptions()) {
-        try {
           wb.put("key".getBytes(), "value".getBytes());
           rDb.write(wOpts, wb);
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -289,16 +205,9 @@ public class ReadOnlyTest {
           readOnlyColumnFamilyHandleList);
            final WriteBatch wb = new WriteBatch();
            final WriteOptions wOpts = new WriteOptions()) {
-        try {
           wb.put(readOnlyColumnFamilyHandleList.get(0), "key".getBytes(),
               "value".getBytes());
           rDb.write(wOpts, wb);
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle :
-              readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }
@@ -318,14 +227,7 @@ public class ReadOnlyTest {
       try (final DBOptions options = new DBOptions();
            final RocksDB rDb = RocksDB.openReadOnly(options, dbFolder.getRoot().getAbsolutePath(),
                cfDescriptors, readOnlyColumnFamilyHandleList, true);) {
-        try {
+        // no-op... should have raised an error as errorIfWalFileExists=true
-          // no-op... should have raised an error as errorIfWalFileExists=true
-
-        } finally {
-          for (final ColumnFamilyHandle columnFamilyHandle : readOnlyColumnFamilyHandleList) {
-            columnFamilyHandle.close();
-          }
-        }
       }
     }
   }