## What changes were proposed in this pull request?

Radix sort require that half of array as free (as temporary space), so we use 0.5 as the scale factor to make sure that BytesToBytesMap will not have more items than 1/2 of capacity. Turned out this is not true, the current implementation of append() could leave 1 more item than the threshold (1/2 of capacity) in the array, which break the requirement of radix sort (fail the assert in 2.2, or fail to insert into InMemorySorter in 2.1).

This PR fix the off-by-one bug in BytesToBytesMap.

This PR also fix a bug that the array will never grow if it fail to grow once (stay as initial capacity), introduced by #15722 .

## How was this patch tested?

Added regression test.

Author: Davies Liu <davies@databricks.com>

Closes #16844 from davies/off_by_one.

(cherry picked from commit 3d0c3af0)
Signed-off-by: Davies Liu <davies.liu@gmail.com>

## What changes were proposed in this pull request?

The search function of paged table is not available because of we don't skip the hash data of the reqeust path.

![](https://issues.apache.org/jira/secure/attachment/12852996/screenshot-1.png

)

## How was this patch tested?

Tested manually with my browser.

Author: Stan Zhai <zhaishidan@haizhi.com>

Closes #16953 from stanzhai/fix-webui-paged-table.

(cherry picked from commit 021062af)
Signed-off-by: Sean Owen <sowen@cloudera.com>

## What changes were proposed in this pull request?

fix test broken by git merge for #16739

## How was this patch tested?

manual

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #16950 from felixcheung/fixrtest.

## What changes were proposed in this pull request?

`StreamingQuery.explain` doesn't show the correct streaming physical plan right now because `ExplainCommand` receives a runtime batch plan and its `logicalPlan.isStreaming` is always false.

This PR adds `streaming` parameter to `ExplainCommand` to allow `StreamExecution` to specify that it's a streaming plan.

Examples of the explain outputs:

- streaming DataFrame.explain()
```
== Physical Plan ==
*HashAggregate(keys=[value#518], functions=[count(1)])
+- StateStoreSave [value#518], OperatorStateId(<unknown>,0,0), Append, 0
   +- *HashAggregate(keys=[value#518], functions=[merge_count(1)])
      +- StateStoreRestore [value#518], OperatorStateId(<unknown>,0,0)
         +- *HashAggregate(keys=[value#518], functions=[merge_count(1)])
            +- Exchange hashpartitioning(value#518, 5)
               +- *HashAggregate(keys=[value#518], functions=[partial_count(1)])
                  +- *SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
                     +- *MapElements <function1>, obj#517: java.lang.String
                        +- *DeserializeToObject value#513.toString, obj#516: java.lang.String
                           +- StreamingRelation MemoryStream[value#513], [value#513]
```

- StreamingQuery.explain(extended = false)
```
== Physical Plan ==
*HashAggregate(keys=[value#518], functions=[count(1)])
+- StateStoreSave [value#518], OperatorStateId(...,0,0), Complete, 0
   +- *HashAggregate(keys=[value#518], functions=[merge_count(1)])
      +- StateStoreRestore [value#518], OperatorStateId(...,0,0)
         +- *HashAggregate(keys=[value#518], functions=[merge_count(1)])
            +- Exchange hashpartitioning(value#518, 5)
               +- *HashAggregate(keys=[value#518], functions=[partial_count(1)])
                  +- *SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
                     +- *MapElements <function1>, obj#517: java.lang.String
                        +- *DeserializeToObject value#543.toString, obj#516: java.lang.String
                           +- LocalTableScan [value#543]
```

- StreamingQuery.explain(extended = true)
```
== Parsed Logical Plan ==
Aggregate [value#518], [value#518, count(1) AS count(1)#524L]
+- SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
   +- MapElements <function1>, class java.lang.String, [StructField(value,StringType,true)], obj#517: java.lang.String
      +- DeserializeToObject cast(value#543 as string).toString, obj#516: java.lang.String
         +- LocalRelation [value#543]

== Analyzed Logical Plan ==
value: string, count(1): bigint
Aggregate [value#518], [value#518, count(1) AS count(1)#524L]
+- SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
   +- MapElements <function1>, class java.lang.String, [StructField(value,StringType,true)], obj#517: java.lang.String
      +- DeserializeToObject cast(value#543 as string).toString, obj#516: java.lang.String
         +- LocalRelation [value#543]

== Optimized Logical Plan ==
Aggregate [value#518], [value#518, count(1) AS count(1)#524L]
+- SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
   +- MapElements <function1>, class java.lang.String, [StructField(value,StringType,true)], obj#517: java.lang.String
      +- DeserializeToObject value#543.toString, obj#516: java.lang.String
         +- LocalRelation [value#543]

== Physical Plan ==
*HashAggregate(keys=[value#518], functions=[count(1)], output=[value#518, count(1)#524L])
+- StateStoreSave [value#518], OperatorStateId(...,0,0), Complete, 0
   +- *HashAggregate(keys=[value#518], functions=[merge_count(1)], output=[value#518, count#530L])
      +- StateStoreRestore [value#518], OperatorStateId(...,0,0)
         +- *HashAggregate(keys=[value#518], functions=[merge_count(1)], output=[value#518, count#530L])
            +- Exchange hashpartitioning(value#518, 5)
               +- *HashAggregate(keys=[value#518], functions=[partial_count(1)], output=[value#518, count#530L])
                  +- *SerializeFromObject [staticinvoke(class org.apache.spark.unsafe.types.UTF8String, StringType, fromString, input[0, java.lang.String, true], true) AS value#518]
                     +- *MapElements <function1>, obj#517: java.lang.String
                        +- *DeserializeToObject value#543.toString, obj#516: java.lang.String
                           +- LocalTableScan [value#543]
```

## How was this patch tested?

The updated unit test.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16934 from zsxwing/SPARK-19603.

(cherry picked from commit fc02ef95)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?
Right now, we only have info level log after we finish the tests of a Python test file. We should also log the start of a test. So, if a test is hanging, we can tell which test file is running.

## How was this patch tested?
This is a change for python tests.

Author: Yin Huai <yhuai@databricks.com>

Closes #16935 from yhuai/SPARK-19604.

(cherry picked from commit f6c3bba2)
Signed-off-by: Yin Huai <yhuai@databricks.com>

## What changes were proposed in this pull request?

SPARK-19464 removed support for Hadoop 2.5 and earlier, so we can do some cleanup for HDFSMetadataLog.

This PR includes the following changes:
- ~~Remove the workaround codes for HADOOP-10622.~~ Unfortunately, there is another issue [HADOOP-14084](https://issues.apache.org/jira/browse/HADOOP-14084

) that prevents us from removing the workaround codes.
- Remove unnecessary `writer: (T, OutputStream) => Unit` and just call `serialize` directly.
- Remove catching FileNotFoundException.

## How was this patch tested?

Jenkins

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16932 from zsxwing/metadata-cleanup.

(cherry picked from commit 21b4ba2d)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

Add coalesce on DataFrame for down partitioning without shuffle and coalesce on Column

manual, unit tests

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #16739 from felixcheung/rcoalesce.

(cherry picked from commit 671bc08e)
Signed-off-by: Felix Cheung <felixcheung@apache.org>

## What changes were proposed in this pull request?

Revision to structured-streaming-kafka-integration.md to reflect new Batch query specification and options.

zsxwing tdas

Please review http://spark.apache.org/contributing.html

 before opening a pull request.

Author: Tyson Condie <tcondie@gmail.com>

Closes #16918 from tcondie/kafka-docs.

(cherry picked from commit 447b2b53)
Signed-off-by: Tathagata Das <tathagata.das1565@gmail.com>

## What changes were proposed in this pull request?

- this is cause by changes in SPARK-18444, SPARK-18643 that we no longer install Spark when `master = ""` (default), but also related to SPARK-18449 since the real `master` value is not known at the time the R code in `sparkR.session` is run. (`master` cannot default to "local" since it could be overridden by spark-submit commandline or spark config)
- as a result, while running SparkR as a package in IDE is working fine, CRAN check is not as it is launching it via non-interactive script
- fix is to add check to the beginning of each test and vignettes; the same would also work by changing `sparkR.session()` to `sparkR.session(master = "local")` in tests, but I think being more explicit is better.

## How was this patch tested?

Tested this by reverting version to 2.1, since it needs to download the release jar with matching version. But since there are changes in 2.2 (specifically around SparkR ML) that are incompatible with 2.1, some tests are failing in this config. Will need to port this to branch-2.1 and retest with 2.1 release jar.

manually as:
```
# modify DESCRIPTION to revert version to 2.1.0
SPARK_HOME=/usr/spark R CMD build pkg
# run cran check without SPARK_HOME
R CMD check --as-cran SparkR_2.1.0.tar.gz
```

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #16720 from felixcheung/rcranchecktest.

(cherry picked from commit a3626ca3)
Signed-off-by: Shivaram Venkataraman <shivaram@cs.berkeley.edu>

## What changes were proposed in this pull request?

As discussed in [JIRA](https://issues.apache.org/jira/browse/SPARK-19501), this patch addresses the problem where too many HDFS RPCs are made when there are many URIs specified in `spark.yarn.jars`, potentially adding hundreds of RTTs to YARN before the application launches. This becomes significant when submitting the application to a non-local YARN cluster (where the RTT may be in order of 100ms, for example). For each URI specified, the current implementation makes at least two HDFS RPCs, for:

- [Calling `getFileStatus()` before uploading each file to the distributed cache in `ClientDistributedCacheManager.addResource()`](https://github.com/apache/spark/blob/v2.1.0/yarn/src/main/scala/org/apache/spark/deploy/yarn/ClientDistributedCacheManager.scala#L71).
- [Resolving any symbolic links in each of the file URI](https://github.com/apache/spark/blob/v2.1.0/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala#L377-L379), which repeatedly makes HDFS RPCs until the all symlinks are resolved. (see [`FileContext.resolve(Path)`](https://github.com/apache/hadoop/blob/release-2.7.1/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FileContext.java#L2189-L2195), [`FSLinkResolver.resolve(FileContext, Path)`](https://github.com/apache/hadoop/blob/release-2.7.1/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSLinkResolver.java#L79-L112), and [`AbstractFileSystem.resolvePath()`](https://github.com/apache/hadoop/blob/release-2.7.1/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/AbstractFileSystem.java#L464-L468).)

The first `getFileStatus` RPC can be removed, using `statCache` populated with the file statuses retrieved with [the previous `globStatus` call](https://github.com/apache/spark/blob/v2.1.0/yarn/src/main/scala/org/apache/spark/deploy/yarn/Client.scala#L531).

The second one can be largely reduced by caching the symlink resolution results in a mutable.HashMap. This patch adds a local variable in `yarn.Client.prepareLocalResources()` and passes it as an additional parameter to `yarn.Client.copyFileToRemote`.  [The symlink resolution code was added in 2013](https://github.com/apache/spark/commit/a35472e1dd2ea1b5a0b1fb6b382f5a98f5aeba5a#diff-b050df3f55b82065803d6e83453b9706R187

) and has not changed since. I am assuming that this is still required, but otherwise we can remove using `symlinkCache` and symlink resolution altogether.

## How was this patch tested?

This patch is based off 8e8afb3a, currently the latest YARN patch on master. All tests except a few in spark-hive passed with `./dev/run-tests` on my machine, using JDK 1.8.0_112 on macOS 10.12.3; also tested myself with this modified version of SPARK 2.2.0-SNAPSHOT which performed a normal deployment and execution on a YARN cluster without errors.

Author: Jong Wook Kim <jongwook@nyu.edu>

Closes #16916 from jongwook/SPARK-19501.

(cherry picked from commit ab9872db)
Signed-off-by: Marcelo Vanzin <vanzin@cloudera.com>

## What changes were proposed in this pull request?

https://spark.apache.org/docs/latest/sql-programming-guide.html#caching-data-in-memory


In the doc, the call spark.cacheTable(“tableName”) and spark.uncacheTable(“tableName”) actually needs to be spark.catalog.cacheTable and spark.catalog.uncacheTable

## How was this patch tested?
Built the docs and verified the change shows up fine.

Author: Sunitha Kambhampati <skambha@us.ibm.com>

Closes #16919 from skambha/docChange.

(cherry picked from commit 9b5e460a)
Signed-off-by: Xiao Li <gatorsmile@gmail.com>

Spark's I/O encryption uses an ephemeral key for each driver instance.
So driver B cannot decrypt data written by driver A since it doesn't
have the correct key.

The write ahead log is used for recovery, thus needs to be readable by
a different driver. So it cannot be encrypted by Spark's I/O encryption
code.

The BlockManager APIs used by the WAL code to write the data automatically
encrypt data, so changes are needed so that callers can to opt out of
encryption.

Aside from that, the "putBytes" API in the BlockManager does not do
encryption, so a separate situation arised where the WAL would write
unencrypted data to the BM and, when those blocks were read, decryption
would fail. So the WAL code needs to ask the BM to encrypt that data
when encryption is enabled; this code is not optimal since it results
in a (temporary) second copy of the data block in memory, but should be
OK for now until a more performant solution is added. The non-encryption
case should not be affected.

Tested with new unit tests, and by running streaming apps that do
recovery using the WAL data with I/O encryption turned on.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #16862 from vanzin/SPARK-19520.

(cherry picked from commit 0169360e)
Signed-off-by: Marcelo Vanzin <vanzin@cloudera.com>

This patch replaces a single `awaitUninterruptibly()` call with a plain `await()` call in Spark's `network-common` library in order to fix a bug which may cause tasks to be uncancellable.

In Spark's Netty RPC layer, `TransportClientFactory.createClient()` calls `awaitUninterruptibly()` on a Netty future while waiting for a connection to be established. This creates problem when a Spark task is interrupted while blocking in this call (which can happen in the event of a slow connection which will eventually time out). This has bad impacts on task cancellation when `interruptOnCancel = true`.

As an example of the impact of this problem, I experienced significant numbers of uncancellable "zombie tasks" on a production cluster where several tasks were blocked trying to connect to a dead shuffle server and then continued running as zombies after I cancelled the associated Spark stage. The zombie tasks ran for several minutes with the following stack:

```
java.lang.Object.wait(Native Method)
java.lang.Object.wait(Object.java:460)
io.netty.util.concurrent.DefaultPromise.await0(DefaultPromise.java:607)
io.netty.util.concurrent.DefaultPromise.awaitUninterruptibly(DefaultPromise.java:301)
org.apache.spark.network.client.TransportClientFactory.createClient(TransportClientFactory.java:224)
org.apache.spark.network.client.TransportClientFactory.createClient(TransportClientFactory.java:179) => holding Monitor(java.lang.Object1849476028})
org.apache.spark.network.shuffle.ExternalShuffleClient$1.createAndStart(ExternalShuffleClient.java:105)
org.apache.spark.network.shuffle.RetryingBlockFetcher.fetchAllOutstanding(RetryingBlockFetcher.java:140)
org.apache.spark.network.shuffle.RetryingBlockFetcher.start(RetryingBlockFetcher.java:120)
org.apache.spark.network.shuffle.ExternalShuffleClient.fetchBlocks(ExternalShuffleClient.java:114)
org.apache.spark.storage.ShuffleBlockFetcherIterator.sendRequest(ShuffleBlockFetcherIterator.scala:169)
org.apache.spark.storage.ShuffleBlockFetcherIterator.fetchUpToMaxBytes(ShuffleBlockFetcherIterator.scala:
350)
org.apache.spark.storage.ShuffleBlockFetcherIterator.initialize(ShuffleBlockFetcherIterator.scala:286)
org.apache.spark.storage.ShuffleBlockFetcherIterator.<init>(ShuffleBlockFetcherIterator.scala:120)
org.apache.spark.shuffle.BlockStoreShuffleReader.read(BlockStoreShuffleReader.scala:45)
org.apache.spark.sql.execution.ShuffledRowRDD.compute(ShuffledRowRDD.scala:169)
org.apache.spark.rdd.RDD.computeOrReadCheckpoint(RDD.scala:323)
org.apache.spark.rdd.RDD.iterator(RDD.scala:287)
[...]
```

As far as I can tell, `awaitUninterruptibly()` might have been used in order to avoid having to declare that methods throw `InterruptedException` (this code is written in Java, hence the need to use checked exceptions). This patch simply replaces this with a regular, interruptible `await()` call,.

This required several interface changes to declare a new checked exception (these are internal interfaces, though, and this change doesn't significantly impact binary compatibility).

An alternative approach would be to wrap `InterruptedException` into `IOException` in order to avoid having to change interfaces. The problem with this approach is that the `network-shuffle` project's `RetryingBlockFetcher` code treats `IOExceptions` as transitive failures when deciding whether to retry fetches, so throwing a wrapped `IOException` might cause an interrupted shuffle fetch to be retried, further prolonging the lifetime of a cancelled zombie task.

Note that there are three other `awaitUninterruptibly()` in the codebase, but those calls have a hard 10 second timeout and are waiting on a `close()` operation which is expected to complete near instantaneously, so the impact of uninterruptibility there is much smaller.

Manually.

Author: Josh Rosen <joshrosen@databricks.com>

Closes #16866 from JoshRosen/SPARK-19529.

(cherry picked from commit 1c4d10b1)
Signed-off-by: Cheng Lian <lian@databricks.com>

[SPARK-17714][CORE][TEST-MAVEN][TEST-HADOOP2.6] Avoid using ExecutorClassLoader to load Netty generated classes

## What changes were proposed in this pull request?

Netty's `MessageToMessageEncoder` uses [Javassist](https://github.com/netty/netty/blob/91a0bdc17a8298437d6de08a8958d753799bd4a6/common/src/main/java/io/netty/util/internal/JavassistTypeParameterMatcherGenerator.java#L62

) to generate a matcher class and the implementation calls `Class.forName` to check if this class is already generated. If `MessageEncoder` or `MessageDecoder` is created in `ExecutorClassLoader.findClass`, it will cause `ClassCircularityError`. This is because loading this Netty generated class will call `ExecutorClassLoader.findClass` to search this class, and `ExecutorClassLoader` will try to use RPC to load it and cause to load the non-exist matcher class again. JVM will report `ClassCircularityError` to prevent such infinite recursion.

##### Why it only happens in Maven builds

It's because Maven and SBT have different class loader tree. The Maven build will set a URLClassLoader as the current context class loader to run the tests and expose this issue. The class loader tree is as following:

```
bootstrap class loader ------ ... ----- REPL class loader ---- ExecutorClassLoader
|
|
URLClasssLoader
```

The SBT build uses the bootstrap class loader directly and `ReplSuite.test("propagation of local properties")` is the first test in ReplSuite, which happens to load `io/netty/util/internal/__matchers__/org/apache/spark/network/protocol/MessageMatcher` into the bootstrap class loader (Note: in maven build, it's loaded into URLClasssLoader so it cannot be found in ExecutorClassLoader). This issue can be reproduced in SBT as well. Here are the produce steps:
- Enable `hadoop.caller.context.enabled`.
- Replace `Class.forName` with `Utils.classForName` in `object CallerContext`.
- Ignore `ReplSuite.test("propagation of local properties")`.
- Run `ReplSuite` using SBT.

This PR just creates a singleton MessageEncoder and MessageDecoder and makes sure they are created before switching to ExecutorClassLoader. TransportContext will be created when creating RpcEnv and that happens before creating ExecutorClassLoader.

## How was this patch tested?

Jenkins

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16859 from zsxwing/SPARK-17714.

(cherry picked from commit 905fdf0c)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?

When a query uses a temp checkpoint dir, it's better to delete it if it's stopped without errors.

## How was this patch tested?

New unit tests.

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16880 from zsxwing/delete-temp-checkpoint.

(cherry picked from commit 3dbff9be)
Signed-off-by: Burak Yavuz <brkyvz@gmail.com>

## What changes were proposed in this pull request?

Add missing `warnings` import.

## How was this patch tested?

Manual tests.

Author: zero323 <zero323@users.noreply.github.com>

Closes #16846 from zero323/SPARK-19506.

(cherry picked from commit 5e7cd332)
Signed-off-by: Holden Karau <holden@us.ibm.com>

[SPARK-19574][ML][DOCUMENTATION] Fix Liquid Exception: Start indices amount is not equal to end indices amount

### What changes were proposed in this pull request?
```
Liquid Exception: Start indices amount is not equal to end indices amount, see /Users/xiao/IdeaProjects/sparkDelivery/docs/../examples/src/main/java/org/apache/spark/examples/ml/JavaTokenizerExample.java. in ml-features.md
```

So far, the build is broken after merging https://github.com/apache/spark/pull/16789



This PR is to fix it.

## How was this patch tested?
Manual

Author: Xiao Li <gatorsmile@gmail.com>

Closes #16908 from gatorsmile/docMLFix.

(cherry picked from commit 855a1b75)
Signed-off-by: Sean Owen <sowen@cloudera.com>

## What changes were proposed in this pull request?

In `KafkaOffsetReader`, when error occurs, we abort the existing consumer and create a new consumer. In our current implementation, the first consumer and the second consumer would be in the same group (which leads to SPARK-19559), **_violating our intention of the two consumers not being in the same group._**

The cause is that, in our current implementation, the first consumer is created before `groupId` and `nextId` are initialized in the constructor. Then even if `groupId` and `nextId` are increased during the creation of that first consumer, `groupId` and `nextId` would still be initialized to default values in the constructor for the second consumer.

We should make sure that `groupId` and `nextId` are initialized before any consumer is created.

## How was this patch tested?

Ran 100 times of `KafkaSourceSuite`; all passed

Author: Liwei Lin <lwlin7@gmail.com>

Closes #16902 from lw-lin/SPARK-19564-.

(cherry picked from commit 2bdbc870)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

[SPARK-19319][BACKPORT-2.1][SPARKR] SparkR Kmeans summary returns error when the cluster size doesn't equal to k

## What changes were proposed in this pull request?

Backport fix of #16666

## How was this patch tested?

Backport unit tests

Author: wm624@hotmail.com <wm624@hotmail.com>

Closes #16761 from wangmiao1981/kmeansport.

## What changes were proposed in this pull request?

Fix a bug in collect method for collecting timestamp column, the bug can be reproduced as shown in the following codes and outputs:

```
library(SparkR)
sparkR.session(master = "local")
df <- data.frame(col1 = c(0, 1, 2),
                 col2 = c(as.POSIXct("2017-01-01 00:00:01"), NA, as.POSIXct("2017-01-01 12:00:01")))

sdf1 <- createDataFrame(df)
print(dtypes(sdf1))
df1 <- collect(sdf1)
print(lapply(df1, class))

sdf2 <- filter(sdf1, "col1 > 0")
print(dtypes(sdf2))
df2 <- collect(sdf2)
print(lapply(df2, class))
```

As we can see from the printed output, the column type of col2 in df2 is converted to numeric unexpectedly, when NA exists at the top of the column.

This is caused by method `do.call(c, list)`, if we convert a list, i.e. `do.call(c, list(NA, as.POSIXct("2017-01-01 12:00:01"))`, the class of the result is numeric instead of POSIXct.

Therefore, we need to cast the data type of the vector explicitly.

## How was this patch tested?

The patch can be tested manually with the same code above.

Author: titicaca <fangzhou.yang@hotmail.com>

Closes #16689 from titicaca/sparkr-dev.

(cherry picked from commit bc0a0e63)
Signed-off-by: Felix Cheung <felixcheung@apache.org>

## What changes were proposed in this pull request?

Fixes compile errors in generated code when user has case class with a `scala.collections.immutable.Map` instead of a `scala.collections.Map`. Since ArrayBasedMapData.toScalaMap returns the immutable version we can make it work with both.

## How was this patch tested?

Additional unit tests.

Author: Andrew Ray <ray.andrew@gmail.com>

Closes #16161 from aray/fix-map-codegen.

(cherry picked from commit 46d30ac4)
Signed-off-by: Cheng Lian <lian@databricks.com>

## What changes were proposed in this pull request?

Using from_json on a column with an empty string results in: java.util.NoSuchElementException: head of empty list.

This is because `parser.parse(input)` may return `Nil` when `input.trim.isEmpty`

## How was this patch tested?

Regression test in `JsonExpressionsSuite`

Author: Burak Yavuz <brkyvz@gmail.com>

Closes #16881 from brkyvz/json-fix.

(cherry picked from commit d5593f7f)
Signed-off-by: Herman van Hovell <hvanhovell@databricks.com>

## What changes were proposed in this pull request?

Set currentVars to null in GenerateOrdering.genComparisons before genCode is called. genCode ignores INPUT_ROW if currentVars is not null and in genComparisons we want it to use INPUT_ROW.

## How was this patch tested?

Added test with 2 queries in WholeStageCodegenSuite

Author: Bogdan Raducanu <bogdan.rdc@gmail.com>

Closes #16875 from bogdanrdc/SPARK-19512-2.1.

## What changes were proposed in this pull request?
The analyzer currently does not check if a column used in grouping sets is actually nullable itself. This can cause the nullability of the column to be incorrect, which can cause null pointer exceptions down the line. This PR fixes that by also consider the nullability of the column.

This is only a problem for Spark 2.1 and below. The latest master uses a different approach.

Closes https://github.com/apache/spark/pull/16874

## How was this patch tested?
Added a regression test to `SQLQueryTestSuite.grouping_set`.

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #16873 from hvanhovell/SPARK-19509.

## What changes were proposed in this pull request?

`Signaling.cancelOnInterrupt` leaks a SparkContext per call and it makes ReplSuite unstable.

This PR adds `SparkContext.getActive` to allow `Signaling.cancelOnInterrupt` to get the active `SparkContext` to avoid the leak.

## How was this patch tested?

Jenkins

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16825 from zsxwing/SPARK-19481.

(cherry picked from commit 303f00a4)
Signed-off-by: Davies Liu <davies.liu@gmail.com>

This is a follow up PR for merging #16758 to spark 2.1 branch

## What changes were proposed in this pull request?

`mapGroupsWithState` is a new API for arbitrary stateful operations in Structured Streaming, similar to `DStream.mapWithState`

*Requirements*
- Users should be able to specify a function that can do the following
- Access the input row corresponding to a key
- Access the previous state corresponding to a key
- Optionally, update or remove the state
- Output any number of new rows (or none at all)

*Proposed API*
```
// ------------ New methods on KeyValueGroupedDataset ------------
class KeyValueGroupedDataset[K, V] {
	// Scala friendly
	def mapGroupsWithState[S: Encoder, U: Encoder](func: (K, Iterator[V], KeyedState[S]) => U)
        def flatMapGroupsWithState[S: Encode, U: Encoder](func: (K, Iterator[V], KeyedState[S]) => Iterator[U])
	// Java friendly
       def mapGroupsWithState[S, U](func: MapGroupsWithStateFunction[K, V, S, R], stateEncoder: Encoder[S], resultEncoder: Encoder[U])
       def flatMapGroupsWithState[S, U](func: FlatMapGroupsWithStateFunction[K, V, S, R], stateEncoder: Encoder[S], resultEncoder: Encoder[U])
}

// ------------------- New Java-friendly function classes -------------------
public interface MapGroupsWithStateFunction<K, V, S, R> extends Serializable {
  R call(K key, Iterator<V> values, state: KeyedState<S>) throws Exception;
}
public interface FlatMapGroupsWithStateFunction<K, V, S, R> extends Serializable {
  Iterator<R> call(K key, Iterator<V> values, state: KeyedState<S>) throws Exception;
}

// ---------------------- Wrapper class for state data ----------------------
trait KeyedState[S] {
	def exists(): Boolean
  	def get(): S 			// throws Exception is state does not exist
	def getOption(): Option[S]
	def update(newState: S): Unit
	def remove(): Unit		// exists() will be false after this
}
```

Key Semantics of the State class
- The state can be null.
- If the state.remove() is called, then state.exists() will return false, and getOption will returm None.
- After that state.update(newState) is called, then state.exists() will return true, and getOption will return Some(...).
- None of the operations are thread-safe. This is to avoid memory barriers.

*Usage*
```
val stateFunc = (word: String, words: Iterator[String, runningCount: KeyedState[Long]) => {
    val newCount = words.size + runningCount.getOption.getOrElse(0L)
    runningCount.update(newCount)
   (word, newCount)
}

dataset					                        // type is Dataset[String]
  .groupByKey[String](w => w)        	                // generates KeyValueGroupedDataset[String, String]
  .mapGroupsWithState[Long, (String, Long)](stateFunc)	// returns Dataset[(String, Long)]
```

## How was this patch tested?
New unit tests.

Author: Tathagata Das <tathagata.das1565@gmail.com>

Closes #16850 from tdas/mapWithState-branch-2.1.

This is a backport of https://github.com/apache/spark/commit/73ee73945e369a862480ef4ac64e55c797bd7d90

## What changes were proposed in this pull request?
The optimizer tries to remove redundant alias only projections from the query plan using the `RemoveAliasOnlyProject` rule. The current rule identifies removes such a project and rewrites the project's attributes in the **entire** tree. This causes problems when parts of the tree are duplicated (for instance a self join on a temporary view/CTE)  and the duplicated part contains the alias only project, in this case the rewrite will break the tree.

This PR fixes these problems by using a blacklist for attributes that are not to be moved, and by making sure that attribute remapping is only done for the parent tree, and not for unrelated parts of the query plan.

The current tree transformation infrastructure works very well if the transformation at hand requires little or a global contextual information. In this case we need to know both the attributes that were not to be moved, and we also needed to know which child attributes were modified. This cannot be done easily using the current infrastructure, and solutions typically involves transversing the query plan multiple times (which is super slow). I have moved around some code in `TreeNode`, `QueryPlan` and `LogicalPlan`to make this much more straightforward; this basically allows you to manually traverse the tree.

## How was this patch tested?
I have added unit tests to `RemoveRedundantAliasAndProjectSuite` and I have added integration tests to the `SQLQueryTestSuite.union` and `SQLQueryTestSuite.cte` test cases.

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #16843 from hvanhovell/SPARK-18609-2.1.

There is a typo in http://spark.apache.org/docs/latest/structured-streaming-kafka-integration.html#creating-a-kafka-source-stream

 , python example n1 uses `readStream()` instead of `readStream`

Just removed the parenthesis.

Author: manugarri <manuel.garrido.pena@gmail.com>

Closes #16836 from manugarri/fix_kafka_python_doc.

(cherry picked from commit 5a0569ce)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?

addBatch method in Sink trait is supposed to be a synchronous method to coordinate with the fault-tolerance design in StreamingExecution (being different with the compute() method in DStream)

We need to add more notes in the comments of this method to remind the developers

## How was this patch tested?

existing tests

Author: CodingCat <zhunansjtu@gmail.com>

Closes #16840 from CodingCat/SPARK-19499.

(cherry picked from commit d4cd9757)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

Today, you can start a stream that reads from kafka. However, given kafka's configurable retention period, it seems like sometimes you might just want to read all of the data that is available now. As such we should add a version that works with spark.read as well.
The options should be the same as the streaming kafka source, with the following differences:
startingOffsets should default to earliest, and should not allow latest (which would always be empty).
endingOffsets should also be allowed and should default to latest. the same assign json format as startingOffsets should also be accepted.
It would be really good, if things like .limit(n) were enough to prevent all the data from being read (this might just work).

KafkaRelationSuite was added for testing batch queries via KafkaUtils.

Author: Tyson Condie <tcondie@gmail.com>

Closes #16686 from tcondie/SPARK-18682.

(cherry picked from commit 8df44440)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?

SPARK-19444 imports not being present in documentation

## How was this patch tested?

Manual

## Disclaimer

Contribution is original work and I license the work to the project under the project’s open source license

Author: Aseem Bansal <anshbansal@users.noreply.github.com>

Closes #16789 from anshbansal/patch-1.

(cherry picked from commit aee2bd2c)
Signed-off-by: Sean Owen <sowen@cloudera.com>

## What changes were proposed in this pull request?

```
Caused by: java.lang.IllegalArgumentException: Wrong FS: s3a://**************/checkpoint/7b2231a3-d845-4740-bfa3-681850e5987f/metadata, expected: file:///
	at org.apache.hadoop.fs.FileSystem.checkPath(FileSystem.java:649)
	at org.apache.hadoop.fs.RawLocalFileSystem.pathToFile(RawLocalFileSystem.java:82)
	at org.apache.hadoop.fs.RawLocalFileSystem.deprecatedGetFileStatus(RawLocalFileSystem.java:606)
	at org.apache.hadoop.fs.RawLocalFileSystem.getFileLinkStatusInternal(RawLocalFileSystem.java:824)
	at org.apache.hadoop.fs.RawLocalFileSystem.getFileStatus(RawLocalFileSystem.java:601)
	at org.apache.hadoop.fs.FilterFileSystem.getFileStatus(FilterFileSystem.java:421)
	at org.apache.hadoop.fs.FileSystem.exists(FileSystem.java:1426)
	at org.apache.spark.sql.execution.streaming.StreamMetadata$.read(StreamMetadata.scala:51)
	at org.apache.spark.sql.execution.streaming.StreamExecution.<init>(StreamExecution.scala:100)
	at org.apache.spark.sql.streaming.StreamingQueryManager.createQuery(StreamingQueryManager.scala:232)
	at org.apache.spark.sql.streaming.StreamingQueryManager.startQuery(StreamingQueryManager.scala:269)
	at org.apache.spark.sql.streaming.DataStreamWriter.start(DataStreamWriter.scala:262)
```

Can easily replicate on spark standalone cluster by providing checkpoint location uri scheme anything other than "file://" and not overriding in config.

WorkAround  --conf spark.hadoop.fs.defaultFS=s3a://somebucket

 or set it in sparkConf or spark-default.conf

## How was this patch tested?

existing ut

Author: uncleGen <hustyugm@gmail.com>

Closes #16815 from uncleGen/SPARK-19407.

(cherry picked from commit 7a0a630e)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?
The SQL parser can mistake a `WHEN (...)` used in `CASE` for a function call. This happens in cases like the following:
```sql
select case when (1) + case when 1 > 0 then 1 else 0 end = 2 then 1 else 0 end
from tb
```
This PR fixes this by re-organizing the case related parsing rules.

## How was this patch tested?
Added a regression test to the `ExpressionParserSuite`.

Author: Herman van Hovell <hvanhovell@databricks.com>

Closes #16821 from hvanhovell/SPARK-19472.

(cherry picked from commit cb2677b8)
Signed-off-by: gatorsmile <gatorsmile@gmail.com>

## What changes were proposed in this pull request?

When connecting timeout, `ask` may fail with a confusing message:

```
17/02/01 23:15:19 INFO Worker: Connecting to master ...
java.lang.IllegalArgumentException: requirement failed: TransportClient has not yet been set.
        at scala.Predef$.require(Predef.scala:224)
        at org.apache.spark.rpc.netty.RpcOutboxMessage.onTimeout(Outbox.scala:70)
        at org.apache.spark.rpc.netty.NettyRpcEnv$$anonfun$ask$1.applyOrElse(NettyRpcEnv.scala:232)
        at org.apache.spark.rpc.netty.NettyRpcEnv$$anonfun$ask$1.applyOrElse(NettyRpcEnv.scala:231)
        at scala.concurrent.Future$$anonfun$onFailure$1.apply(Future.scala:138)
        at scala.concurrent.Future$$anonfun$onFailure$1.apply(Future.scala:136)
        at scala.concurrent.impl.CallbackRunnable.run(Promise.scala:32)
```

It's better to provide a meaningful message.

## How was this patch tested?

Jenkins

Author: Shixiong Zhu <shixiong@databricks.com>

Closes #16773 from zsxwing/connect-timeout.

(cherry picked from commit 8303e20c)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?

Copying of the killed status was missing while getting the newTaskInfo object by dropping the unnecessary details to reduce the memory usage. This patch adds the copying of the killed status to newTaskInfo object, this will correct the display of the status from wrong status to KILLED status in Web UI.

## How was this patch tested?

Current behaviour of displaying tasks in stage UI page,

| Index | ID | Attempt | Status | Locality Level | Executor ID / Host | Launch Time | Duration | GC Time | Input Size / Records | Write Time | Shuffle Write Size / Records | Errors |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|143	|10	|0	|SUCCESS	|NODE_LOCAL	|6 / x.xx.x.x stdout stderr|2017/01/25 07:49:27	|0 ms |		|0.0 B / 0		| |0.0 B / 0	|TaskKilled (killed intentionally)|
|156	|11	|0	|SUCCESS	|NODE_LOCAL	|5 / x.xx.x.x stdout stderr|2017/01/25 07:49:27	|0 ms |		|0.0 B / 0		| |0.0 B / 0	|TaskKilled (killed intentionally)|

Web UI display after applying the patch,

| Index | ID | Attempt | Status | Locality Level | Executor ID / Host | Launch Time | Duration | GC Time | Input Size / Records | Write Time | Shuffle Write Size / Records | Errors |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|143	|10	|0	|KILLED	|NODE_LOCAL	|6 / x.xx.x.x stdout stderr|2017/01/25 07:49:27	|0 ms |		|0.0 B / 0		|  | 0.0 B / 0	| TaskKilled (killed intentionally)|
|156	|11	|0	|KILLED	|NODE_LOCAL	|5 / x.xx.x.x stdout stderr|2017/01/25 07:49:27	|0 ms |		|0.0 B / 0		|  |0.0 B / 0	| TaskKilled (killed intentionally)|

Author: Devaraj K <devaraj@apache.org>

Closes #16725 from devaraj-kavali/SPARK-19377.

(cherry picked from commit df4a27cc)
Signed-off-by: Shixiong Zhu <shixiong@databricks.com>

## What changes were proposed in this pull request?
Fix brokens links in ml-pipeline and ml-tuning
`<div data-lang="scala">`  ->   `<div data-lang="scala" markdown="1">`

## How was this patch tested?
manual tests

Author: Zheng RuiFeng <ruifengz@foxmail.com>

Closes #16754 from zhengruifeng/doc_api_fix.

(cherry picked from commit 04ee8cf6)
Signed-off-by: Sean Owen <sowen@cloudera.com>

[SPARK-19378][SS] Ensure continuity of stateOperator and eventTime metrics even if there is no new data in trigger

In StructuredStreaming, if a new trigger was skipped because no new data arrived, we suddenly report nothing for the metrics `stateOperator`. We could however easily report the metrics from `lastExecution` to ensure continuity of metrics.

Regression test in `StreamingQueryStatusAndProgressSuite`

Author: Burak Yavuz <brkyvz@gmail.com>

Closes #16716 from brkyvz/state-agg.

(cherry picked from commit 081b7add)
Signed-off-by: Tathagata Das <tathagata.das1565@gmail.com>

## What changes were proposed in this pull request?

backport #16721 to branch-2.1

## How was this patch tested?

manual

Author: Felix Cheung <felixcheung_m@hotmail.com>

Closes #16749 from felixcheung/rsubsetdocbackport.

### What changes were proposed in this pull request?
Currently, the function `to_json` allows users to provide options for generating JSON. However, it does not pass it to `JacksonGenerator`. Thus, it ignores the user-provided options. This PR is to fix it. Below is an example.

```Scala
val df = Seq(Tuple1(Tuple1(java.sql.Timestamp.valueOf("2015-08-26 18:00:00.0")))).toDF("a")
val options = Map("timestampFormat" -> "dd/MM/yyyy HH:mm")
df.select(to_json($"a", options)).show(false)
```
The current output is like
```
+--------------------------------------+
|structtojson(a)                       |
+--------------------------------------+
|{"_1":"2015-08-26T18:00:00.000-07:00"}|
+--------------------------------------+
```

After the fix, the output is like
```
+-------------------------+
|structtojson(a)          |
+-------------------------+
|{"_1":"26/08/2015 18:00"}|
+-------------------------+
```
### How was this patch tested?
Added test cases for both `from_json` and `to_json`

Author: gatorsmile <gatorsmile@gmail.com>

Closes #16745 from gatorsmile/toJson.

(cherry picked from commit f9156d29)
Signed-off-by: gatorsmile <gatorsmile@gmail.com>