We have changed the output format of `printSchema`. This PR will update our SQL programming guide to show the updated format. Also, it fixes a typo (the value type of `StructType` in Java API).

Author: Yin Huai <huai@cse.ohio-state.edu>

Closes #2630 from yhuai/sqlDoc and squashes the following commits:

267d63e [Yin Huai] Update the output of printSchema and fix a typo.

### Problem

The section "Using the shell" in Spark Programming Guide (https://spark.apache.org/docs/latest/programming-guide.html#using-the-shell) says that we can run pyspark REPL through IPython.
But a folloing command does not run IPython but a default Python executable.

```
$ IPYTHON=1 ./bin/pyspark
Python 2.7.8 (default, Jul  2 2014, 10:14:46)
...
```

the spark/bin/pyspark script on the commit b235e013 decides which executable and options it use folloing way.

1. if PYSPARK_PYTHON unset
   * → defaulting to "python"
2. if IPYTHON_OPTS set
   * → set IPYTHON "1"
3. some python scripts passed to ./bin/pyspak → run it with ./bin/spark-submit
   * out of this issues scope
4. if IPYTHON set as "1"
   * → execute $PYSPARK_PYTHON (default: ipython) with arguments $IPYTHON_OPTS
   * otherwise execute $PYSPARK_PYTHON

Therefore, when PYSPARK_PYTHON is unset, python is executed though IPYTHON is "1".
In other word, when PYSPARK_PYTHON is unset, IPYTHON_OPS and IPYTHON has no effect on decide which command to use.

PYSPARK_PYTHON | IPYTHON_OPTS | IPYTHON | resulting command | expected command
---- | ---- | ----- | ----- | -----
(unset → defaults to python) | (unset) | (unset) | python | (same)
(unset → defaults to python) | (unset) | 1 | python | ipython
(unset → defaults to python) | an_option | (unset → set to 1) | python an_option | ipython an_option
(unset → defaults to python) | an_option | 1 | python an_option | ipython an_option
ipython | (unset) | (unset) | ipython | (same)
ipython | (unset) | 1 | ipython | (same)
ipython | an_option | (unset → set to 1) | ipython an_option | (same)
ipython | an_option | 1 | ipython an_option | (same)

### Suggestion

The pyspark script should determine firstly whether a user wants to run IPython or other executables.

1. if IPYTHON_OPTS set
   * set IPYTHON "1"
2.  if IPYTHON has a value "1"
   * PYSPARK_PYTHON defaults to "ipython" if not set
3. PYSPARK_PYTHON defaults to "python" if not set

See the pull request for more detailed modification.

Author: cocoatomo <cocoatomo77@gmail.com>

Closes #2554 from cocoatomo/issues/cannot-run-ipython-without-options and squashes the following commits:

d2a9b06 [cocoatomo] [SPARK-3706][PySpark] Use PYTHONUNBUFFERED environment variable instead of -u option
264114c [cocoatomo] [SPARK-3706][PySpark] Remove the sentence about deprecated environment variables
42e02d5 [cocoatomo] [SPARK-3706][PySpark] Replace environment variables used to customize execution of PySpark REPL
10d56fb [cocoatomo] [SPARK-3706][PySpark] Cannot run IPython REPL with IPYTHON set to "1" and PYSPARK_PYTHON unset

This change reorders the replicas returned by
HadoopRDD#getPreferredLocations so that replicas cached by HDFS are at
the start of the list.  This requires Hadoop 2.5 or higher; previous
versions of Hadoop do not expose the information needed to determine
whether a replica is cached.

Author: Colin Patrick Mccabe <cmccabe@cloudera.com>

Closes #1486 from cmccabe/SPARK-1767 and squashes the following commits:

338d4f8 [Colin Patrick Mccabe] SPARK-1767: Prefer HDFS-cached replicas when scheduling data-local tasks

The following code gives error.
```
sqlContext.registerFunction("len", (s: String) => s.length)
sqlContext.sql("select len(foo) as a, count(1) from t1 group by len(foo)").collect()
```
Because SQl parser creates the aliases to the functions in grouping expressions with generated alias names. So if user gives the alias names to the functions inside projection then it does not match the generated alias name of grouping expression.
This kind of queries are working in Hive.
So the fix I have given that if user provides alias to the function in projection then don't generate alias in grouping expression,use the same alias.

Author: ravipesala <ravindra.pesala@huawei.com>

Closes #2511 from ravipesala/SPARK-3371 and squashes the following commits:

9fb973f [ravipesala] Removed aliases to grouping expressions.
f8ace79 [ravipesala] Fixed the testcase issue
bad2fd0 [ravipesala] SPARK-3371 : Fixed Renaming a function expression with group by gives error

This commit exists to close the following pull requests on Github:

Closes #1375 (close requested by 'pwendell')
Closes #476 (close requested by 'mengxr')
Closes #2502 (close requested by 'pwendell')
Closes #2391 (close requested by 'andrewor14')

FutureAction is the only type exposed through the async APIs, so
for job IDs to be useful they need to be exposed there. The complication
is that some async jobs run more than one job (e.g. takeAsync),
so the exposed ID has to actually be a list of IDs that can actually
change over time. So the interface doesn't look very nice, but...

Change is actually small, I just added a basic test to make sure
it works.

Author: Marcelo Vanzin <vanzin@cloudera.com>

Closes #2337 from vanzin/SPARK-3446 and squashes the following commits:

e166a68 [Marcelo Vanzin] Fix comment.
1fed2bc [Marcelo Vanzin] [SPARK-3446] Expose underlying job ids in FutureAction.

This patch forces use of commons http client 4.2 in Kinesis-asl profile so that the AWS SDK does not run into dependency conflicts

Author: aniketbhatnagar <aniket.bhatnagar@gmail.com>

Closes #2535 from aniketbhatnagar/Kinesis-HttpClient-Dep-Fix and squashes the following commits:

aa2079f [aniketbhatnagar] Merge branch 'Kinesis-HttpClient-Dep-Fix' of https://github.com/aniketbhatnagar/spark into Kinesis-HttpClient-Dep-Fix
73f55f6 [aniketbhatnagar] SPARK-3638 | Forced a compatible version of http client in kinesis-asl profile
70cc75b [aniketbhatnagar] deleted merge files
725dbc9 [aniketbhatnagar] Merge remote-tracking branch 'origin/Kinesis-HttpClient-Dep-Fix' into Kinesis-HttpClient-Dep-Fix
4ed61d8 [aniketbhatnagar] SPARK-3638 | Forced a compatible version of http client in kinesis-asl profile
9cd6103 [aniketbhatnagar] SPARK-3638 | Forced a compatible version of http client in kinesis-asl profile

case ```ShortType```, we should add short value to hive row. Int value may lead to some problems.

Author: scwf <wangfei1@huawei.com>

Closes #2551 from scwf/fix-addColumnValue and squashes the following commits:

08bcc59 [scwf] ColumnValue.shortValue for short type

This change avoids a NPE during context initialization when settings are present.

Author: Michael Armbrust <michael@databricks.com>

Closes #2583 from marmbrus/configNPE and squashes the following commits:

da2ec57 [Michael Armbrust] Do all hive session state initilialization in lazy val

This reverts commit 6390aae4.

Considering `Command.executeCollect()` simply delegates to `Command.sideEffectResult`, we no longer need to leave the latter `protected[sql]`.

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #2431 from liancheng/narrow-scope and squashes the following commits:

1bfc16a [Cheng Lian] Made Command.sideEffectResult protected

BinaryType is derived from NativeType and added Ordering support.

Author: Venkata Ramana G <ramana.gollamudihuawei.com>

Author: Venkata Ramana Gollamudi <ramana.gollamudi@huawei.com>

Closes #2617 from gvramana/binarytype_sort and squashes the following commits:

1cf26f3 [Venkata Ramana Gollamudi] Supported Sorting of BinaryType

add case for VoidObjectInspector in ```inspectorToDataType```

Author: scwf <wangfei1@huawei.com>

Closes #2552 from scwf/inspectorToDataType and squashes the following commits:

453d892 [scwf] add case for VoidObjectInspector

The below query gives error
sql("SELECT k FROM (SELECT \`key\` AS \`k\` FROM src) a")
It gives error because the aliases are not cleaned so it could not be resolved in further processing.

Author: ravipesala <ravindra.pesala@huawei.com>

Closes #2594 from ravipesala/SPARK-3708 and squashes the following commits:

d55db54 [ravipesala] Fixed SPARK-3708 (Backticks aren't handled correctly is aliases)

https://issues.apache.org/jira/browse/SPARK-3658

And keep the `CLASS_NOT_FOUND_EXIT_STATUS` and exit message in `SparkSubmit.scala`.

Author: WangTaoTheTonic <barneystinson@aliyun.com>
Author: WangTao <barneystinson@aliyun.com>

Closes #2509 from WangTaoTheTonic/thriftserver and squashes the following commits:

5dcaab2 [WangTaoTheTonic] issue about coupling
8ad9f95 [WangTaoTheTonic] generalization
598e21e [WangTao] take thrift server as a daemon

Author: Michael Armbrust <michael@databricks.com>

Closes #2598 from marmbrus/hiveClientLock and squashes the following commits:

ca89fe8 [Michael Armbrust] Lock hive client when creating tables

SQL example code for Python, as shown on [SQL Programming Guide](https://spark.apache.org/docs/1.0.2/sql-programming-guide.html)

Author: jyotiska <jyotiska123@gmail.com>

Closes #2521 from jyotiska/sql_example and squashes the following commits:

1471dcb [jyotiska] added imports for sql
b25e436 [jyotiska] pep 8 compliance
43fd10a [jyotiska] lines broken to maintain 80 char limit
b4fdf4e [jyotiska] removed blank lines
83d5ab7 [jyotiska] added inferschema and applyschema to the demo
306667e [jyotiska] replaced blank line with end line
c90502a [jyotiska] fixed new line
4939a70 [jyotiska] added new line at end for python style
0b46148 [jyotiska] fixed appname for python sql example
8f67b5b [jyotiska] added python sql example

topicpMap to topicMap

Author: Gaspar Munoz <munozs.88@gmail.com>

Closes #2614 from gasparms/patch-1 and squashes the following commits:

00aab2c [Gaspar Munoz] Typo error in KafkaWordCount example

MD5 of query strings in `createQueryTest` calls are used to generate golden files, leaving trailing spaces there can be really dangerous. Got bitten by this while working on #2616: my "smart" IDE automatically removed a trailing space and makes Jenkins fail.

(Really should add "no trailing space" to our coding style guidelines!)

Author: Cheng Lian <lian.cs.zju@gmail.com>

Closes #2619 from liancheng/kill-trailing-space and squashes the following commits:

034f119 [Cheng Lian] Kill dangerous trailing space in query string

Jetty server use MultiException to handle exceptions when start server
refer https://github.com/eclipse/jetty.project/blob/jetty-8.1.14.v20131031/jetty-server/src/main/java/org/eclipse/jetty/server/Server.java

So in ```isBindCollision``` add the logical to cover MultiException

Author: scwf <wangfei1@huawei.com>

Closes #2611 from scwf/fix-isBindCollision and squashes the following commits:

984cb12 [scwf] optimize the fix
3a6c849 [scwf] fix bug in isBindCollision

Non-root user use port 1- 1024 to start jetty server will get the exception " java.net.SocketException: Permission denied", so not use these ports

Author: scwf <wangfei1@huawei.com>

Closes #2610 from scwf/1-1024 and squashes the following commits:

cb8cc76 [scwf] do not use port 1 - 1024

Call SparkContext.stop() in all examples (and touch up minor nearby code style issues while at it)

Author: Sean Owen <sowen@cloudera.com>

Closes #2575 from srowen/SPARK-2626 and squashes the following commits:

5b2baae [Sean Owen] Call SparkContext.stop() in all examples (and touch up minor nearby code style issues while at it)

1. broadcast is triggle unexpected
2. fd is leaked in JVM (also leak in parallelize())
3. broadcast is not unpersisted in JVM after RDD is not be used any more.

cc JoshRosen , sorry for these stupid bugs.

Author: Davies Liu <davies.liu@gmail.com>

Closes #2603 from davies/fix_broadcast and squashes the following commits:

080a743 [Davies Liu] fix bugs in broadcast large closure of RDD

Added directory to be deleted into maven-clean-plugin in pom.xml.

Author: Masayoshi TSUZUKI <tsudukim@oss.nttdata.co.jp>

Closes #2613 from tsudukim/feature/SPARK-3757 and squashes the following commits:

8804bfc [Masayoshi TSUZUKI] Modified indent.
67c7171 [Masayoshi TSUZUKI] [SPARK-3757] mvn clean doesn't delete some files

Thread names are useful for correlating failures.

Author: Reynold Xin <rxin@apache.org>

Closes #2600 from rxin/log4j and squashes the following commits:

83ffe88 [Reynold Xin] [SPARK-3748] Log thread name in unit test logs

DecisionTreeRunner functionality additions:
* Allow user to pass in a test dataset
* Do not print full model if the model is too large.

As part of this, modify DecisionTreeModel and RandomForestModel to allow printing less info.  Proposed updates:
* toString: prints model summary
* toDebugString: prints full model (named after RDD.toDebugString)

Similar update to Python API:
* __repr__() now prints a model summary
* toDebugString() now prints the full model

CC: mengxr  chouqin manishamde codedeft  Small update (whomever can take a look).  Thanks!

Author: Joseph K. Bradley <joseph.kurata.bradley@gmail.com>

Closes #2604 from jkbradley/dtrunner-update and squashes the following commits:

b2b3c60 [Joseph K. Bradley] re-added python sql doc test, temporarily removed before
07b1fae [Joseph K. Bradley] repr() now prints a model summary toDebugString() now prints the full model
1d0d93d [Joseph K. Bradley] Updated DT and RF to print less when toString is called. Added toDebugString for verbose printing.
22eac8c [Joseph K. Bradley] Merge remote-tracking branch 'upstream/master' into dtrunner-update
e007a95 [Joseph K. Bradley] Updated DecisionTreeRunner to accept a test dataset.

[SPARK-3747] TaskResultGetter could incorrectly abort a stage if it cannot get result for a specific task

Author: Reynold Xin <rxin@apache.org>

Closes #2599 from rxin/SPARK-3747 and squashes the following commits:

a74c04d [Reynold Xin] Added a line of comment explaining NonFatal
0e8d44c [Reynold Xin] [SPARK-3747] TaskResultGetter could incorrectly abort a stage if it cannot get result for a specific task

This patch add profiling support for PySpark, it will show the profiling results
before the driver exits, here is one example:

```
============================================================
Profile of RDD<id=3>
============================================================
         5146507 function calls (5146487 primitive calls) in 71.094 seconds

   Ordered by: internal time, cumulative time

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
  5144576   68.331    0.000   68.331    0.000 statcounter.py:44(merge)
       20    2.735    0.137   71.071    3.554 statcounter.py:33(__init__)
       20    0.017    0.001    0.017    0.001 {cPickle.dumps}
     1024    0.003    0.000    0.003    0.000 t.py:16(<lambda>)
       20    0.001    0.000    0.001    0.000 {reduce}
       21    0.001    0.000    0.001    0.000 {cPickle.loads}
       20    0.001    0.000    0.001    0.000 copy_reg.py:95(_slotnames)
       41    0.001    0.000    0.001    0.000 serializers.py:461(read_int)
       40    0.001    0.000    0.002    0.000 serializers.py:179(_batched)
       62    0.000    0.000    0.000    0.000 {method 'read' of 'file' objects}
       20    0.000    0.000   71.072    3.554 rdd.py:863(<lambda>)
       20    0.000    0.000    0.001    0.000 serializers.py:198(load_stream)
    40/20    0.000    0.000   71.072    3.554 rdd.py:2093(pipeline_func)
       41    0.000    0.000    0.002    0.000 serializers.py:130(load_stream)
       40    0.000    0.000   71.072    1.777 rdd.py:304(func)
       20    0.000    0.000   71.094    3.555 worker.py:82(process)
```

Also, use can show profile result manually by `sc.show_profiles()` or dump it into disk
by `sc.dump_profiles(path)`, such as

```python
>>> sc._conf.set("spark.python.profile", "true")
>>> rdd = sc.parallelize(range(100)).map(str)
>>> rdd.count()
100
>>> sc.show_profiles()
============================================================
Profile of RDD<id=1>
============================================================
         284 function calls (276 primitive calls) in 0.001 seconds

   Ordered by: internal time, cumulative time

   ncalls  tottime  percall  cumtime  percall filename:lineno(function)
        4    0.000    0.000    0.000    0.000 serializers.py:198(load_stream)
        4    0.000    0.000    0.000    0.000 {reduce}
     12/4    0.000    0.000    0.001    0.000 rdd.py:2092(pipeline_func)
        4    0.000    0.000    0.000    0.000 {cPickle.loads}
        4    0.000    0.000    0.000    0.000 {cPickle.dumps}
      104    0.000    0.000    0.000    0.000 rdd.py:852(<genexpr>)
        8    0.000    0.000    0.000    0.000 serializers.py:461(read_int)
       12    0.000    0.000    0.000    0.000 rdd.py:303(func)
```
The profiling is disabled by default, can be enabled by "spark.python.profile=true".

Also, users can dump the results into disks automatically for future analysis, by "spark.python.profile.dump=path_to_dump"

This is bugfix of #2351 cc JoshRosen

Author: Davies Liu <davies.liu@gmail.com>

Closes #2556 from davies/profiler and squashes the following commits:

e68df5a [Davies Liu] Merge branch 'master' of github.com:apache/spark into profiler
858e74c [Davies Liu] compatitable with python 2.6
7ef2aa0 [Davies Liu] bugfix, add tests for show_profiles and dump_profiles()
2b0daf2 [Davies Liu] fix docs
7a56c24 [Davies Liu] bugfix
cba9463 [Davies Liu] move show_profiles and dump_profiles to SparkContext
fb9565b [Davies Liu] Merge branch 'master' of github.com:apache/spark into profiler
116d52a [Davies Liu] Merge branch 'master' of github.com:apache/spark into profiler
09d02c3 [Davies Liu] Merge branch 'master' into profiler
c23865c [Davies Liu] Merge branch 'master' into profiler
15d6f18 [Davies Liu] add docs for two configs
dadee1a [Davies Liu] add docs string and clear profiles after show or dump
4f8309d [Davies Liu] address comment, add tests
0a5b6eb [Davies Liu] fix Python UDF
4b20494 [Davies Liu] add profile for python

1. doc updates
2. simple checks on vector dimensions
3. use column major for matrices

davies jkbradley

Author: Xiangrui Meng <meng@databricks.com>

Closes #2548 from mengxr/mllib-py-clean and squashes the following commits:

6dce2df [Xiangrui Meng] address comments
116b5db [Xiangrui Meng] use np.dot instead of array.dot
75f2fcc [Xiangrui Meng] fix python style
fefce00 [Xiangrui Meng] better check of vector size with more tests
067ef71 [Xiangrui Meng] majored -> major
ef853f9 [Xiangrui Meng] update python linalg api and small fixes

Author: Reynold Xin <rxin@apache.org>

Closes #2602 from rxin/warning and squashes the following commits:

130186b [Reynold Xin] Remove compiler warning from TaskContext change.

Since it looked quite easy, I took the liberty of making a quick PR that just uses `Utils.startServiceOnPort` to fix this. It works locally for me.

Author: Sean Owen <sowen@cloudera.com>

Closes #2601 from srowen/SPARK-3744 and squashes the following commits:

ddc9319 [Sean Owen] Avoid port contention in tests by retrying several ports for Flume stream

[By request](https://github.com/apache/spark/pull/2588#issuecomment-57266871), and because it also makes sense.

Author: Nicholas Chammas <nicholas.chammas@gmail.com>

Closes #2597 from nchammas/timeout-commit-hash and squashes the following commits:

3d90714 [Nicholas Chammas] Revert "testing: making timeout 1 minute"
2353c95 [Nicholas Chammas] testing: making timeout 1 minute
e3a477e [Nicholas Chammas] post commit hash with timeout

for details, see: https://issues.apache.org/jira/browse/SPARK-3745

Author: shane knapp <incomplete@gmail.com>

Closes #2596 from shaneknapp/SPARK-3745 and squashes the following commits:

c95eea9 [shane knapp] SPARK-3745 - fix check-license to properly download and check jar

As suggested by mateiz , and because it came up on the mailing list again last week, this attempts to document that ordering of elements is not guaranteed across RDD evaluations in groupBy, zip, and partition-wise RDD methods. Suggestions welcome about the wording, or other methods that need a note.

Author: Sean Owen <sowen@cloudera.com>

Closes #2508 from srowen/SPARK-3356 and squashes the following commits:

b7c96fd [Sean Owen] Undo change to programming guide
ad4aeec [Sean Owen] Don't mention ordering in partition-wise methods, reword description of ordering for zip methods per review, and add similar note to programming guide, which mentions groupByKey (but not zip methods)
fce943b [Sean Owen] Note that ordering of elements is not guaranteed across RDD evaluations in groupBy, zip, and partition-wise RDD methods

This reverts commit 0bbe7fae.

When using spark-submit in `cluster` mode to submit a job to a Spark Standalone
cluster, if the JAVA_HOME environment variable was set on the submitting
machine then DriverRunner would attempt to use the submitter's JAVA_HOME to
launch the driver process (instead of the worker's JAVA_HOME), causing the
driver to fail unless the submitter and worker had the same Java location.

This commit fixes this by reading JAVA_HOME from sys.env instead of
command.environment.

Author: Josh Rosen <joshrosen@apache.org>

Closes #2586 from JoshRosen/SPARK-3734 and squashes the following commits:

e9513d9 [Josh Rosen] [SPARK-3734] DriverRunner should not read SPARK_HOME from submitter's environment.

The problem was that the 2nd argument in RemoveBroadcast is not tellMaster! It is "removeFromDriver". Basically when removeFromDriver is not true, we don't report broadcast block removal back to the driver, and then other executors mistakenly think that the executor would still have the block, and try to fetch from it.

cc @tdas

Author: Reynold Xin <rxin@apache.org>

Closes #2588 from rxin/debug and squashes the following commits:

6dab2e3 [Reynold Xin] Don't log random messages.
f430686 [Reynold Xin] Always report broadcast removal back to master.
2a13f70 [Reynold Xin] iii

This changes the way we send MapStatus from executors back to driver for large stages (>2000 tasks). For large stages, we no longer send one byte per block. Instead, we just send the average block size.

This makes large jobs (tens of thousands of tasks) much more reliable since the driver no longer sends huge amount of data.

Author: Reynold Xin <rxin@apache.org>

Closes #2470 from rxin/mapstatus and squashes the following commits:

822ff54 [Reynold Xin] Code review feedback.
3b86f56 [Reynold Xin] Added MimaExclude.
f89d182 [Reynold Xin] Fixed a bug in MapStatus
6a0401c [Reynold Xin] [SPARK-3613] Record only average block size in MapStatus for large stages.

Author: Reynold Xin <rxin@apache.org>

Closes #2581 from rxin/minor-cleanup and squashes the following commits:

736a91b [Reynold Xin] Minor cleanup of code.