Develop Reference

Android annotation processing - generate different code for different build flavor

I'm building a library that requires some annotation processing to generate code. I now run into an issue that the release build doesn't need to have as much code as the debug build does (since this is a library for modifying configuration variants - primarily used for testing purposes). The following code illustrates the situations. Let's say I want to create a class ConfigManager from some annotated classes and properties. In debug builds, I need this much:
public class ConfigManager {
public Class getConfigClass() {
return abc.class;
}
public void method1() {
doSomething1();
}
public void method2() {
doSomething2();
}
public void method3() {
doSomething3();
}
}
While in release builds, I only need this much:
public class ConfigManager {
public Class getConfigClass() {
return abc.class;
}
}
I have a feeling it may be possible by writing a Gradle plugin to check for build flavor at compile time and invoke a different processor/or somehow pass a parameter to a processor to generate different code. However this topic is pretty new to me so I'm not sure how to achieve this. A couple hours of googling also didnt help. So I'm wondering if anyone could give me a direction or example? Thanks

Pass an option (release=true/false) to your processor.
From javac https://docs.oracle.com/javase/8/docs/technotes/tools/windows/javac.html
-Akey[=value]
Specifies options to pass to annotation processors. These options are not interpreted by javac directly, but are made available for use by individual processors. The key value should be one or more identifiers separated by a dot (.).
In combination with Processor.html#getSupportedOptions https://docs.oracle.com/javase/8/docs/api/javax/annotation/processing/Processor.html#getSupportedOptions
Returns the options recognized by this processor. An implementation of the processing tool must provide a way to pass processor-specific options distinctly from options passed to the tool itself, see getOptions.
Implementation outline:
public Set<String> getSupportedOptions() {
Set<String> set = new HashSet<>();
set.add("release");
return set;
}
// -Arelease=true
boolean isRelease(ProcessingEnvironment env) {
return Boolean.parseBoolean(env.getOptions().get("release"));
}
See Pass options to JPAAnnotationProcessor from Gradle for how to pass options in a gradle build.

How to set up a configured embedder for use of meta filters (-skip) with Serenity, JBehave and Selenium

While creating new scenarios I only want to test the scenario I am currently working with. For this purpose I want to use the Meta: #skip tag before my scenarios. As I found out I have to use the embedder to configure the used meta tags, so I tried:
configuredEmbedder().useMetaFilters(Arrays.asList("-skip"));
but actually this still has no effect on my test scenarios. I used it in the constructor of my SerenityStories test suite definition. Here is the complete code of this class:
public class AcceptanceTestSuite extends SerenityStories {
#Managed
WebDriver driver;
public AcceptanceTestSuite() {
System.setProperty("webdriver.chrome.driver", "D:/files/chromedriver/chromedriver.exe");
System.setProperty("chrome.switches", "--lang=en");
System.setProperty("restart.browser.each.scenario", "true");
configuredEmbedder().useMetaFilters(Arrays.asList("-skip"));
runSerenity().withDriver("chrome");
}
#Override
public Configuration configuration() {
Configuration configuration = super.configuration();
Keywords keywords = new LocalizedKeywords(DEFAULTSTORYLANGUAGE);
Properties properties = configuration.storyReporterBuilder().viewResources();
properties.setProperty("encoding", "UTF-8");
configuration.useKeywords(keywords)
.useStoryParser(new RegexStoryParser(keywords, new ExamplesTableFactory(new LoadFromClasspath(this.getClass()))))
.useStoryLoader(new UTF8StoryLoader()).useStepCollector(new MarkUnmatchedStepsAsPending(keywords))
.useDefaultStoryReporter(new ConsoleOutput(keywords)).storyReporterBuilder().withKeywords(keywords).withViewResources(properties);
return configuration;
}
}
Is this the wrong place or have I missed something? Still all scenarios are executed.
EDIT:
I changed following classes and now I think that it "works"
public AcceptanceTestSuite() {
System.setProperty("webdriver.chrome.driver", "D:/files/chromedriver/chromedriver.exe");
System.setProperty("chrome.switches", "--lang=de");
System.setProperty("restart.browser.each.scenario", "true");
this.useEmbedder(configuredEmbedder());
runSerenity().withDriver("chrome");
}
#Override
public Embedder configuredEmbedder() {
final Embedder embedder = new Embedder();
embedder.embedderControls()
.useThreads(1)
.doGenerateViewAfterStories(true)
.doIgnoreFailureInStories(false)
.doIgnoreFailureInView(false)
.doVerboseFailures(true);
final Configuration configuration = configuration();
embedder.useConfiguration(configuration);
embedder.useStepsFactory(stepsFactory());
embedder.useMetaFilters(Arrays.asList("-skip"));
return embedder;
}
But now I get the message [pool-1-thread-1] INFO net.serenitybdd.core.Serenity - TEST IGNORED but the scenario is still executed. Only in the result page I get the info that this scenario is ignored (but still executed). Is there a way to SKIP the scenario so it won't run?

I could not make it run with using configuredEmbedder() but by adding -Dmetafilter="+working -finished" as goals in my mvn run configurations and using the tags #working for scenarios I'm working with and which I want to run and #finsihed for scenarios I don't want to execute. Still I have to change the run configuration if I want to change the meta tags so it is not very comfortable but still I get what I was looking for.

As long as you document it well (some doc in https://github.com/serenity-bdd/the-serenity-book would be brilliant), I think as a JBehave/Serenity user you are well enough placed to decide which option makes the most sense.

Investigation
I debugged the serenity-jbehave classes, trying to understand why setting
configuredEmbedder().useMetaFilters(Collections.singletonList("-skip"))
is not working in all the possible places I put it within my class extending the SerenityStories, I found the strategic code place where metaFilters in ExtendedEmbedder#embedder are overwritten with what we define in our class into settings from serenity-jbehave.
This method is SerenityReportingRunner#createPerformableTree:
private PerformableTree createPerformableTree(List<CandidateSteps> candidateSteps, List<String> storyPaths) {
ExtendedEmbedder configuredEmbedder = this.getConfiguredEmbedder();
configuredEmbedder.useMetaFilters(getMetaFilters());
BatchFailures failures = new BatchFailures(configuredEmbedder.embedderControls().verboseFailures());
PerformableTree performableTree = configuredEmbedder.performableTree();
RunContext context = performableTree.newRunContext(getConfiguration(), candidateSteps,
configuredEmbedder.embedderMonitor(), configuredEmbedder.metaFilter(), failures);
performableTree.addStories(context, configuredEmbedder.storyManager().storiesOfPaths(storyPaths));
return performableTree;
}
This line changes the set metaFilters:
configuredEmbedder.useMetaFilters(getMetaFilters());
It overrides the current metaFilters value.
Going further the call chain, we get to the logic that defines from where it gets metaFilters, i.e. where we can actually set it.
SerenityReportingRunner#createPerformableTree
↓
SerenityReportingRunner#getMetaFilters
↓
SerenityReportingRunner#getMetafilterSetting
This is the method we need!
private String getMetafilterSetting() {
Optional<String> environmentMetafilters = getEnvironmentMetafilters();
Optional<String> annotatedMetafilters = getAnnotatedMetafilters(testClass);
Optional<String> thucAnnotatedMetafilters = getThucAnnotatedMetafilters(testClass);
return environmentMetafilters.orElse(annotatedMetafilters.orElse(thucAnnotatedMetafilters.orElse("")));
}
As we see here, the metaFilters can be defined in three places, and they override each other. In the priority lowering order, they are:
Value of metafilter (exactly all lowercase!) VM property.
Value of on net.serenitybdd.jbehave.annotations.Metafilter annotation on our SerenityStories class.
Value of on net.thucydides.jbehave.annotations.Metafilter annotation on our SerenityStories class. This annotation is deprecated, but left in place for backwards-compatibility.
Solution that is working with the current serenity-jbehave version
I've tried/debugged all these three options, they work and override each other as described above.
1. Use environment metafilter property
Added this to my JVM run arguments:
-Dmetafilter=skip
2. Use the modern #Metafilter annotation
import net.serenitybdd.jbehave.SerenityStories;
import net.serenitybdd.jbehave.annotations.Metafilter;
#Metafilter("-skip")
public class Acceptance extends SerenityStories {
3. Use the deprecated #Metafilter annotation
import net.serenitybdd.jbehave.SerenityStories;
import net.thucydides.jbehave.annotations.Metafilter;
#Metafilter("-skip") // warned as deprecated
public class Acceptance extends SerenityStories {
Solution for my current project is to use the current #Metafilter("-skip") annotation on my test class, to not depend on/have to change VM properties of the particular Jenkins/local dev execution.
Possible pull request to make
https://github.com/serenity-bdd/serenity-core/issues/95 — here Serenity guys have suggested me to do a PR with this fix, since they are not concentrated on Serenity + JBehave now.
I understand where to make the changes (in the code chain described above), but I don't know what overriding logic should be:
— MetaFilters from configuredEmbedder override any of ENV/annotation MetaFilters.
OR
— Any ENV/annotation MetaFilters override Metafilters from configuredEmbedder
OR
— MetaFilters from configuredEmbedder are merged with ENV/annotation MetaFilters. This option required merging priority.
Any suggestions?
In any type of fix, I would prefer add the explicit logs about how the overriding is now working into SerenityReportingRunner#getMetafilterSetting, since the current behaviour is really non-obvious and took lots of time to investigate.

Efficient way of reading Config file

We're developing a Java application that reads a Config file at runtime. My question is that which of the following scenario is efficient for reading a Config file.
Scenario #1: Retrieves a value from config by opening the file, get the value, then close the file.
So this means that file will be open and close every time retrieving a value.
Scenario #2: Open the file during initialization, then expose the object statically across the runtime.
File will be open once, then retrieving a value using the Config object.
Honestly, we currently using the scenario #2. A reason why we choose it because Config file will be open once. Opening file needs syncrhonization, which may lead to untimely retrieval of value. Also, scenario #1 may cause runtime error if the Config file is moved from it's absolute path (anything is possible). But scenario #1 is efficient when it comes in modifying the Config values during runtime.
So which is efficient?

Is your application a mulit-threaded application? if yes, you need to make sure that you have scenario #1 with necessary synchronisation and semaphores. The reason is that your config file is a general item in your application which will be used by all the threads. You don't want the config file reading operation to be interleaved. Even with single threaded operation, it is good to do #1 because you will have less chances of having IO Error. The RTE that you mentioned in your question can happen with anything if you decide to move the file (? Why would you if you need it at a certain place?).

If I should have to access the file more than once, probably I would create a class with a field for each configuration, I would read the file once (only to initialize the class fields) and then I would close the file. In this way you read the file once, during the init, and then you could simply access the configuration by reading the field values stored in the class.
public class Configuration
{
private static String confOne;
private static int confTwo;
private static boolean confThree;
public static init(File configFile) {
/* read the file and init fields */
}
public static String getConfigOne() {
return configOne;
}
public static int getConfigTwo() {
return configOne;
}
public static boolean getConfigThree() {
return configOne;
}
}
A little advice: tries to never hold open a file (or resources) unless absolutely necessary.

I think neither of the scenarios is the best one:
As you you have already stated in sencario #1 you may have a lot of unnecessary IO-Workload and in #2 you cannot change config parameters dynamically at runtime.
I suggest to use a mixture of both. You can load your configuration statically once and then check periodically, if changes have happend. If so, reload your config.
You can see how it may be done by inspecting Java's ResourceBundle-Class. In fact, if the config can be placed as properties-file in your classpath, you can (ab?)use this implementation for your purpose:
private static Control MY_CONTROL = new Control()
{
#Override
public long getTimeToLive(String baseName, Locale locale)
{
return MY_TTL; //make shure, that changes are checked periodically
}
};
public static String getParamter(String name)
{
ResourceBundle config = ResourceBundle.getBundle("config", MY_CONTROL);
return config.getString(name);
}

Jenkins; Inject Environment Variable in Jelly field?

This has been bugging me for a little while, there is a list with environment variables and I want to use them in the configuration of one of my builds on my own custom plugin, as such:
So in this case I would like the ${WORKSPACE} to resolve to a path that has been configured by the environment.
Anyone know how to do this? I can't seem to find it as a Jelly tag.

The type of variable expansion you are asking for can only be performed by the build step itself. If this is your own plug-in then you can apply the change I suggest here, otherwise you can always ask the plug-in author to do so. Short of either you'll have to rely on the work-around Slav provided.
If you do have access to the source for the plug-in here's how to expand variables during execution of the build step. I assume the build step class is SanityTestResultsToJUnitXMLBuilder. Inside this class's perform method you need to expand the source and destination directory fields. I added place holders for other pieces of code you'd normally find in a build step for brevity.
public class SanityTestResultsToJUnitXMLBuilder extends Builder {
private final String sourceDirectory;
private final String destinationDirectory;
/* Constructor and getters typically appear here. */
#Override
public void perform(AbstractBuild<?, ?> build, Launcher launcher, BuildListener listener) throws InterruptedException, IOException {
EnvVars environment = build.getEnvironment(listener);
String expandedSourceDirectory = environment.expand(sourceDirectory);
String expandedDestinationDirectory = environment.expand(destinationDirectory);
/* The rest of the perform() logic goes here */
}
/* Other methods typically appear here. */
/* The Descriptor typically appears here. */
}

Not sure what exactly you are asking for, but you can get the $WORKSPACE environment variable by:
def workspace = manager.build.getEnvVars()["WORKSPACE"]

Sensible unit test possible?

Could a sensible unit test be written for this code which extracts a rar archive by delegating it to a capable tool on the host system if one exists?
I can write a test case based on the fact that my machine runs linux and the unrar tool is installed, but if another developer who runs windows would check out the code the test would fail, although there would be nothing wrong with the extractor code.
I need to find a way to write a meaningful test which is not binded to the system and unrar tool installed.
How would you tackle this?
public class Extractor {
private EventBus eventBus;
private ExtractCommand[] linuxExtractCommands = new ExtractCommand[]{new LinuxUnrarCommand()};
private ExtractCommand[] windowsExtractCommands = new ExtractCommand[]{};
private ExtractCommand[] macExtractCommands = new ExtractCommand[]{};
#Inject
public Extractor(EventBus eventBus) {
this.eventBus = eventBus;
}
public boolean extract(DownloadCandidate downloadCandidate) {
for (ExtractCommand command : getSystemSpecificExtractCommands()) {
if (command.extract(downloadCandidate)) {
eventBus.fireEvent(this, new ExtractCompletedEvent());
return true;
}
}
eventBus.fireEvent(this, new ExtractFailedEvent());
return false;
}
private ExtractCommand[] getSystemSpecificExtractCommands() {
String os = System.getProperty("os.name");
if (Pattern.compile("linux", Pattern.CASE_INSENSITIVE).matcher(os).find()) {
return linuxExtractCommands;
} else if (Pattern.compile("windows", Pattern.CASE_INSENSITIVE).matcher(os).find()) {
return windowsExtractCommands;
} else if (Pattern.compile("mac os x", Pattern.CASE_INSENSITIVE).matcher(os).find()) {
return macExtractCommands;
}
return null;
}
}

Could you not pass the class a Map<String,ExtractCommand[]> instances and then make an abstract method, say GetOsName, for getting the string to match. then you could look up the match string in the map to get the extract command in getSystemSpecificExtractCommands method. This would allow you to inject a list containing a mock ExtractCommand and override the GetOsName method to return the key of your mock command, so you could test that when the extract worked, the eventBus is fired etc.
private Map<String,EvenetCommand[]> eventMap;
#Inject
public Extractor(EventBus eventBus, Map<String,EventCommand[]> eventMap) {
this.eventBus = eventBus;
this.eventMap = eventMap;
}
private ExtractCommand[] getSystemSpecificExtractCommands() {
String os = GetOsName();
return eventMap.Get(os);
}
protected GetOsName();
{
return System.getProperty("os.name");
}

I would look for some pure java APIs for manipulating rar files. This way the code will not be system dependent.
A quick search on google returned this:
http://www.example-code.com/java/rar_unrar.asp

Start with a mock framework. You'll need to refactor a bit, as you will need to ensure that some of those private and local scope properties/variables can be overridden if need be.
Then when you are testing Extract, you make sure you've mocked out the commands, and ensure that the Extract method is called on your mocked objects. You'll also want to ensure that your event got fired too.
Now to make it more testable you can use constructor or property injection. Either way, you'll need to make the private ExtractCommand arrays overriddable.
Sorry, don't have time to recode it, and post, but that should just about get you started nicely.
Good luck.
EDIT. It does sound like you are more after a functional test anyway if you want to test that it is actually extracted correctly.

Testing can be tricky, especially getting the divides right between the different types of tests and when they should be run and what their responsibilities are. This is even more so with cross-platform code.
While it's possible to think of this as 1 code base you are testing, it's really multiple code bases, the generic java code and code for each target platform, so you will need multiple tests.
To begin with unit testing, you will not be exercising the external command. Rather, each platform specific class is tested to see that it generates the correct command line, without actually executing it.
Your java class that hides all the platform specifics (which command to use) has a unit test to verify that it instantiates the correct platform specific class for a given platform. The platform can be a parameter to the core test, so multiple platforms can be "emulated". To take the unit test further, you could mock out the command implementation (e.g. having a RAR file and it's uncompressed form as part of your test data, and the command is a simple copy of the uncompressed data.)
Once these unit tests are in place and green, you then can move on to functional tests, where the real platform specific commands are executed. Of course, these functional tests have to be run on the actual platform. Each functional test corresponds to a platform specific class that knows how to create the correct commandline to unrar.
Your build is configured to exclude tests for classes that don't apply to the current platform, for example, so LinuxUnrarer is not tested on Windows. The platform independent java class is always tested, and it will instantiate the appropriate platform specific test. This gives you a integration test to see that the system works end to end.
As to cross platform UNRAR, there is a java RAR scanner, but it doesn't decompress.