Changes

This page details the changes made in the current version only.
Earlier changes are detailed in the History of Previous Changes.

Version 4.0

Summary

New and Noteworthy
Incompatible changes
Bug fixes
Improvements
Non-functional changes
Known problems and workarounds
Thanks

New and Noteworthy

Core improvements

JMeter now supports JAVA 9.

New Boundary Extractor element available which provides easy extraction with better performances

New JSON Assertion element available to assert on JSON responses.

New Precise Throughput Timer element available which produces Poisson arrivals with given constant throughput.

JMS Point-to-Point sampler has been enhanced with read, browse, clear options.

Best property values are now selected on many Test Elements to ensure best practices are the defaults:

Newly added If Controller now uses by default Expression which is the most performing option.
Newly added JSR223 Test Element now cache compiled script by default if language used provides this feature.

Loop controller and ForEach Controller now expose their current iteration as a variable named __jm__<Name of your element>__idx that you can use like this for example for a Loop Controller named MyLoopController:

${__jm__<MyLoopController>__idx}

. See Bug 61802

Cookies are now shown in View Results Tree during recording. They were previously always shown as empty.

Response Assertion now allows you to customize assertion message and assert on Request Data.

UX improvements

JMeter now uses Darcula LAF by default

Workbench has been dropped from UI, you can now use Non Test Elements as immediate children of Test Plan.

Menu UX have been improved to make most used elements available more rapidly.

HTTP(S) Test Script Recorder now allows you to name your transactions while recording in a more human readable way.

UX improvements made on, among the most notable :

Module Controller informs user at least one Controller is required
Function Helper Dialog (The wizard that helps using and testing functions) has been improved in many fields.
Switch Controller trims text to avoid issues when a space is introduced before/after name
Test Plan is now saved before running the test plan

Functions

New Function __digest provides easy computing of SHA-XXX, MDX hashes:

${__digest(MD5,Apache JMeter 4.0 rocks !,,,)}

will return 0e16c3ce9b6c9971c69ad685fd875d2b

New Function __dateTimeConvert provides easy conversion between date formats:

${__dateTimeConvert(01 Jan 2017,dd MMM yyyy,dd/MM/yyyy,)}

will return 01/01/2017

New Function __changeCase provides ability to switch to Upper / Lower / Capitalized cases

${__changeCase(Avaro omnia desunt\, inopi pauca\, sapienti nihil,UPPER,)}

will return AVARO OMNIA DESUNT, INOPI PAUCA, SAPIENTI NIHIL

New Functions __isVarDefined and __isPropDefined provide testing of properties and variables availability

${__isPropDefined(START.HMS)}

will return true

${__isVarDefined(JMeterThread.last_sample_ok)}

will return true

Scripting and Plugin Development

You can now call SampleResult#setIgnore() if you don't want your sampler to be visible in results

JavaSamplerContext used by AbstractJavaSamplerClient has been enhanced with new methods to easy plugin development.

JMeter now distributes additional Maven sources and javadoc artifacts into Maven repository

Plugins can now register listeners to be notified when a Test Plan is opened/closed

Live Reporting and Web Report

InfluxDB backend listener now allows you to add custom tags by adding them with prefix TAG_, see Bug 61794

In Web Report responseTime distribution graph is more precise

Some bugfixes have been made on report generation, see Bug 61900, Bug 6190061956, Bug 61899. Graphs Latency Vs Request and Response Time Vs Request did not exceed 1000 RPS due to Bug 61962

Configuration of JMeter environment

JVM settings for the JMeter start scripts can be placed in a separate file (bin/setenv.sh on Unix and bin\setenv.bat on Windows), that gets called on startup. The startup script itself does not have to be edited anymore.

Incompatible changes

Start time and End date of Thread Group have been removed, see Bug 61549
In distributed testing, mode Hold has been removed. Use alternative and more efficient modes
For 3^rd party plugins, the following method in org.apache.jmeter.gui.tree.JMeterTreeNode has been dropped for migration to Java 9 ( Bug 61529)
```
public Enumeration<JMeterTreeNode> children()
```
tearDown Thread Group will now run on stop and shutdown of a test by default. If you don't want this behaviour, uncheck Run tearDown Thread Groups after shutdown of main threads on Test Plan element, see Bug 61656
Properties sampleresult.getbytes.headers_size and sampleresult.getbytes.body_real_size have been dropped, see Bug 61587
JMeter will now save your test plan whenever you run it. This behaviour can be controlled by property save_automatically_before_run, see Bug 61731
Workbench element has been dropped, you now directly add Non Test Element as children of Test Plan. When loading a Test Plan that contains the element JMeter will move the Mirror Server, Property Display and HTTP(s) Test Script Recorder elements as direct children of Test Plan. For any other element, it will create a Test Fragment element called Workbench Test Fragment and move the elements in it.
Following classes have been dropped (org.apache.jmeter.functions.util.ArgumentEncoder, org.apache.jmeter.functions.util.ArgumentDecoder), see Pull request #335
In JMS Point-to-Point sampler, setting timeout to 0 will now mean infinite timeout while previously it would be switched to 2000 ms, see Bug 61829
When Assertions are at different scopes, they are executed starting with the most OUTER one to the most INNER one. See Bug 61846
JMeter now starts by default using English locale. This change is due to missing translations in many supported languages. You can change locale by modifying in jmeter and jmeter.bat (or preferably setenv.sh/setenv.bat) the JVM_ARGS system property values. We'd also be very grateful if you can contribute translations in supported languages.
SwitchController now trims by default the content of switch to avoid issue related to unwanted spaces. See Bug 61771
JMeter JVM heap settings have changed from -Xms512m -Xmx512m to -Xms1g -Xmx1g

Improvements

HTTP Samplers and Test Script Recorder

Pull request #316 - Warn about empty truststore loading. Contributed by Vincent Herilier (https://github.com/vherilier)
Bug 61639 - HTTP(S) Test Script Recorder: In request filtering tab, uncheck by default "Notify Child Listeners of filtered samplers"
Bug 61672 - HTTP(S) Test Script Recorder: Have the ability to choose the sampler name while keeping the ability to just add a prefix
Bug 53957 - HTTP Request: In Parameters tab, allow pasting of content coming from Firefox and Chrome (unparsed)
Bug 61587 - Drop properties sampleresult.getbytes.headers_size and sampleresult.getbytes.body_real_size
Bug 61843 - HTTP(S) Test Script Recorder: Add SAN to JMeter generated CA Certificate. Contributed by Matthew Buckett
Bug 61901 - Support for https.cipherSuites System property. Contributed by Jeremy Arnold (jeremy at arnoldzoo.org)

Other samplers

Bug 61544 - JMS Point-to-Point Sampler: Enhance communication styles with read, browse, clear. Based on a contribution by Benny van Wijngaarden (benny at smaragd-it.nl)
Bug 61829 - JMS Point-to-Point: If Receive Queue is empty and a timeout is set, it is not taken into account. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61739 - Java Request / JavaSamplerClient: Improve org.apache.jmeter.protocol.java.sampler.JavaSamplerContext
Bug 61762 - Start Next Thread Loop should be used everywhere

Controllers

Bug 61675 - If Controller: Use expression by default and add a warning when the other mode is used. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61770 - Module Controller: Inform user in UI that he needs to have at least one Controller in his plan. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61771 - SwitchController: Switch field should be trimmed by safety

Listeners

Bug 57760 - View Results Tree: Cookie Header is wrongly shown as empty (no cookies) when viewing a recorder Sample Result. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61769 - View Results Tree: Use syntax highlighter in XPath Tester, JSON Path Tester and CSS/JQuery Tester. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61776 - View Results Tree: Expansion of Add expand/collapse all menu in render XML view. Contributed by Maxime Chassagneux and Graham Russell
Bug 61852 - View Results Tree: Add a Boundary Extractor Tester
Bug 61794 - Influxdb backend: Add as many custom tags as wanted by just create new lines and prefix theirs name by "TAG_" on the GUI backend listener

Timers, Assertions, Config, Pre- & Post-Processors

Bug 60213 - New component: Boundary based extractor
Bug 61845 - New Component JSON Assertion based on AtlanBH JSON Path Assertion donated to JMeter-Plugins and migrated into JMeter core by Artem Fedorov (artem at blazemeter.com)
Bug 61931 - New Component: Precise Throughput Timer, timer that produces Poisson arrivals with given constant throughput. Contributed by Vladimir Sitnikov (sitnikov.vladimir at gmail.com)
Bug 61644 - HTTP Cache Manager: "Use Cache-Control/Expires header when processing GET requests" should be checked by default
Bug 61645 - Response Assertion: Add ability to assert on Request Data
Bug 51140 - Response Assertion: add ability to set a specific error/failure message that is later shown in the Assertion Result. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61534 - Convert AssertionError to a failed assertion, allowing users to use assert in their code. Fixing a regression introduced in 3.2
Bug 61756 - Extractors: Improve label name "Reference name" to make it clear what it makes
Bug 61758 - Apply to: field in Extractors, Assertions: When entering a value in JMeter Variable Name, the radio box JMeter Variable Name should be selected by default. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61846 - Scoped Assertion should follow same order of evaluation as Post Processors

Functions

Bug 61724 - Add __digest function to provide computing of Hashes (SHA-XXX, MDX). Based on a contribution by orimarko at gmail.com
Bug 61735 - Add __dateTimeConvert function to provide date formats conversions. Based on a contribution by orimarko at gmail.com
Bug 61760 - Add __isPropDefined and __isVarDefined functions to know if property or variable exist. Contributed by orimarko at gmail.com
Bug 61759 - Add __changeCase function to change different cases of a string. Based on a contribution by orimarko at gmail.com
Bug 61561 - Function helper dialog should display exception in result
Bug 61738 - Function Helper Dialog: Add Copy in Generate and clarify labels. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 62027 - Help: Introduce property help.local to allow choosing between local (offline) documentation and online documentation
Bug 61593 - Remove Detail, Add, Add from Clipboard, Delete buttons in Function Helper GUI

I18N

Bug 61606 - Translate button Browse… in some elements (which use FileEditor class)
Bug 61747 - HTTP(S) Test Script Recorder: add the missing doc to "Create transaction after request (ms)"

Report / Dashboard

Bug 61871 - Reduce jmeter.reportgenerator.graph.responseTimeDistribution.property.set_granularity default value from 500ms to 100ms
Bug 61879 - Remove useless files in HTML report template

General

Bug 61591 - Drop Workbench from test tree. Implemented by Artem Fedorov (artem at blazemeter.com) and contributed by BlazeMeter Ltd.
Bug 61549 - Thread Group: Remove start and end date
Bug 61529 - Migration to Java 9. Partly contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61709 - SampleResult: Add a method setIgnore() to make JMeter ignore the SampleResult and not send it to listeners
Bug 61806 - Allow to use SampleResult#setIgnore() in post-processors and assertions script (JSR223 elements)
Bug 61607 - Add browse button in all BeanShell elements to select BeanShell script
Bug 61627 - Don't clear LogView anymore when clicking on Warning/Errors Indicator
Bug 61629 - Add Think Times to Children menu should not consider disabled elements
Bug 61655 - SampleSender: Drop HoldSampleSender implementation
Bug 61656 - tearDown Thread Group should run by default at stop or shutdown of test
Bug 61659 - JMeterVariables#get() should apply toString() on non string objects
Bug 61555 - Metaspace should be restricted as default
Bug 61693 - JMeter aware of Docker (-XX:+UnlockExperimentalVMOptions -XX:+UseCGroupMemoryLimitForHeap)
Bug 61694 - Add -server option in jmeter.bat
Bug 61697 - Introduce Darcula Look And Feel to make JMeter UI more attractive
Bug 61704 - Toolbar: Improve a bit the right part
Bug 61731 - Enhance Test plan Backup with option to save before run. Based on a contribution by orimarko at gmail.com
Bug 61640 - JSR223 Test Elements: Enable by default caching. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61785 - Add Help → Useful links to create issues and download nightly build
Bug 61808 - Fix main frame position. Implemented by Artem Fedorov (artem at blazemeter.com) and contributed by BlazeMeter Ltd.
Bug 61802 - Loop / ForEach Controller should expose a variable for current iteration. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Pull request #349 - Add i18n resources(zh_CN). Contributed by Helly Guo (https://github.com/hellyguo)
Pull request #351 - Fixed about dialog position on first view. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #352 - Menu bar - added mnemonics to more menu items. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #353 - Re-wrote some existing tests in Spock. Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61919 - UX: Reorder Menus. Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61920 - Plugins: Add ability to listen to Test Plan loading/closing. Contributed by Peter Doornbosch (https://bitbucket.org/pjtr/)
Bug 61935 - Plugins: Let GUI component (dynamically) decide whether it can be added via the menu or not. Contributed by Peter Doornbosch (https://bitbucket.org/pjtr/)
Bug 61969 - When changing LAF through GUI, user should be informed that it is better to restart
Bug 61970 - JMeter now uses English as default locale to avoid missing translations in some locales make UI look weird
Bug 56368 - Create and Deploy source artifacts to Maven central
Bug 61973 - Create and Deploy javadoc artifacts to Maven central
Pull request #371 - Fix example in documentation for XPath Assertion. Contributed by Konstantin Kalinin (kkalinin at hotmail.com)
Bug 62039 - Distributed testing: Provide ability to use SSL

Non-functional changes

Updated to bsh-2.0b6 (from bsh-2.0b5)
Updated to groovy-all-2.4.13 (from groovy-all-2.4.12)
Updated to rhino-1.7.7.2 (from rhino-1.7.7.1)
Updated to tika-core and tika-parsers 1.17 (from 1.16)
Updated to commons-dbcp2-2.2.0 (from 2.1.1)
Updated to caffeine 2.6.1 (from 2.5.5)
Updated to commons-codec-1.11 (from 1.10)
Updated to commons-io-2.6 (from 2.5)
Updated to commons-lang3-3.7 (from 3.6)
Updated to commons-pool2-2.5.0 (from 2.4.2)
Updated to asm-6.0 (from 5.2)
Updated to jsoup-1.11.2 (from 1.10.3)
Updated to cglib-nodep-3.2.6 (from 3.2.5)
Updated to ph-css 6.0.0 (from 5.0.4)
Updated to ph-commons 9.0.0 (from 8.6.6)
Updated to log4j2 2.10.0 (from 2.8.2)
Updated to httpcore 4.4.9 (from 4.4.7)
Updated to httpclient 4.5.5 (from 4.5.3)
Updated to jodd 4.1.4 (from 3.8.6)
Bug 61642 - Improve FTP test coverage
Bug 61641 - Improve JMS test coverage
Bug 61651 - Improve TCP test coverage
Bug 61651 - Improve OS test coverage. Partly contributed by Aleksei Balan (abalanonline at gmail.com)
Pull request #319 - Removed commented out code. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #322 - General JavaDoc cleanup. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #323 - Extracted method and used streams to improve readability. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #324 - Save backup refactor. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #327 - Utilising more modern Java, simplifying code and formatting code and comments. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #332 - Add the spock framework for groovy unit tests. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #334 - Enable running of JUnit tests from within IntelliJ with default config. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #335 - Removed functions.util.* as they don't seem to be used (for many years). Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61867 - Pull request #345 - Updated to latest checkstyle (v8.5), Added many more rules to checkstyle, Included checking of test files and more file types. Contributed by Graham Russell (graham at ham1.co.uk)
Pull request #350 - Parallelised unit tests. Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61966 - Setup Test Results Analyzer in jenkins
Pull request #343 - Reduce the size of some images in the documentation. Contributed by Graham Russell (graham at ham1.co.uk)

Bug fixes

HTTP Samplers and Test Script Recorder

Bug 61569 - JMS Point-to-Point Test Plan: Synchronization issue when putting reply. Contributed by Igor Panainte (panainte.i at gmail.com)

Other Samplers

Bug 61698 - Test Action: It stop is selected, samplers following Test Action can run
Bug 61707 - Test Action: Target is ignored when pause is selected, so it should be disabled
Bug 61827 - JMSPublisher: Don't add new line at the end of the file. Contributed by Graham Russell (graham at ham1.co.uk)

Controllers

Bug 61556 - Clarify in documentation performance impacts of ${} var usage in IfController and groovy. Contributed by Justin McCartney (be_strew at yahoo.co.uk)
Bug 61713 - Test Fragment has option to Change Controller and Insert Parent. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61965 - Module and Include Controller should not allow to add meaningless elements in their context.
Bug 62062 - ThroughputController: StackOverFlowError triggered when throughput=0 (Total Executions or Percentage Executions) Partly implemented by Artem Fedorov (artem.fedorov at blazemeter.com) and contributed by BlazeMeter Ltd.

Listeners

Bug 61742 - BackendListener: fix default value for backend_graphite.send_interval
Bug 61878 - BackendListener: NPE if BackendListenerClient#getDefaultParameters returns null
Bug 61950 - View Results Tree: Content-Type audio/mpegurl is wrongly considered as binary

Timers, Assertions, Config, Pre- & Post-Processors

Bug 61716 - Header Manager: When pasting Headers from Firefox or Chrome spaces are introduced as first character of value

Functions

Bug 61588 - Better log message for __RandomDate() function
Bug 61619 - In Function Helper Dialog, the 1^st function doesn't display default parameters
Bug 61628 - If split string has empty separator default separator is not used
Bug 61752 - __RandomDate: Function does not allow missing last parameter used for variable name

I18N

Report / Dashboard

Bug 61807 - Web Report: fix error in getTop5ErrorMetrics. Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61900 - Report Generator: Report generation fails if separator is a regex reserved char like |
Bug 61925 - CsvSampleReader does not increment row in nextSample(). Contributed by Graham Russell (graham at ham1.co.uk)
Bug 61956 - Report Generation: -f of -forceDeleteResultFile option does not work. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61899 - Report Generation: When jmeter.save.saveservice.print_field_names is false and sample_variables are set report generation fails. Contributed by Ubik Load Pack (support at ubikloadpack.com)
Bug 61962 - Latency Vs Request and Response Time Vs Request graphs do not exceed 1000 RPS. Contributed by Ubik Load Pack (support at ubikloadpack.com)

General

Bug 61661 - Avoid startup/shutdown problems due to 3^rd party Thread Listener plugins throwing RuntimeException
Bug 61625 - File Editor used in BeanInfo behaves strangely under all LAFs with impact on CSVDataSet, JSR223, BSF, Beanshell Element
Bug 61844 - Maven pom.xml: Libraries used in testing should have scope test
Bug 61842 - Saving with no changes causes a save and duplicate, identical backup file

Thanks

We thank all contributors mentioned in bug and improvement sections above:

Igor Panainte (panainte.i at gmail.com)
Emilian Bold (emi at apache.org)
Ubik Load Pack
Justin McCartney (be_strew at yahoo.co.uk)
Vincent Herilier (https://github.com/vherilier)
Aleksei Balan (abalanonline at gmail.com)
Graham Russell (graham at ham1.co.uk)
orimarko at gmail.com
Artem Fedorov (artem at blazemeter.com)
BlazeMeter Ltd
Benny van Wijngaarden (benny at smaragd-it.nl)
Matthew Buckett (https://github.com/buckett)
Helly Guo (https://github.com/hellyguo)
Peter Doornbosch (https://bitbucket.org/pjtr/)
Jeremy Arnold (jeremy at arnoldzoo.org)
Vladimir Sitnikov (sitnikov.vladimir at gmail.com)
Konstantin Kalinin (kkalinin at hotmail.com)

We also thank bug reporters who helped us improve JMeter.
For this release we want to give special thanks to the following reporters for the clear reports and tests made after our fixes:

user7294900 on Stackoverflow (orimarko at gmail.com)

Apologies if we have omitted anyone else.

Known problems and workarounds

View Results Tree may freeze rendering large response particularly if this response has no spaces, see Bug 60816. This is due to an identified Java Bug UI stuck when calling JEditorPane.setText() or JTextArea.setText() with long text without space.

The Once Only controller behaves correctly under a Thread Group or Loop Controller, but otherwise its behaviour is not consistent (or clearly specified).
The numbers that appear to the left of the green box are the number of active threads / total number of threads, the total number of threads only applies to a locally run test, otherwise it will show 0 (see Bug 55510).
Note that under some windows systems you may have this WARNING:
```
java.util.prefs.WindowsPreferences
WARNING: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0
x80000002. Windows RegCreateKeyEx(…) returned error code 5.
```
The fix is to run JMeter as Administrator, it will create the registry key for you, then you can restart JMeter as a normal user and you won't have the warning anymore.
You may encounter the following error:
```
java.security.cert.CertificateException: Certificates does not conform to algorithm constraints
```
if you run a HTTPS request on a web site with a SSL certificate (itself or one of SSL certificates in its chain of trust) with a signature algorithm using MD2 (like md2WithRSAEncryption) or with a SSL certificate with a size lower than 1024 bits. This error is related to increased security in Java 8+.
To allow you to perform your HTTPS request, you can downgrade the security of your Java installation by editing the Java jdk.certpath.disabledAlgorithms property. Remove the MD2 value or the constraint on size, depending on your case.
This property is in this file:
```
JAVA_HOME/jre/lib/security/java.security
```
See Bug 56357 for details.
Under Mac OSX Aggregate Graph will show wrong values due to mirroring effect on numbers. This is due to a known Java bug, see Bug JDK-8065373 The fix is to use JDK8_u45 or later.
View Results Tree may fail to display some HTML code under HTML renderer, see Bug 54586. This is due to a known Java bug which fails to parse "px" units in row/col attributes. See Bug JDK-8031109 The fix is to use JDK9 b65 or later.
JTable selection with keyboard (SHIFT + up/down) is totally unusable with Java 7 on Mac OSX. This is due to a known Java bug JDK-8025126 The fix is to use JDK 8 b132 or later.