BACKGROUND
\nThis post is in addition to the previous article about plugin development but with a focus on UI based plugin implementations. Sometimes it can be really useful to have an UI and make it possible to interact with it by doing some checkboxes selections or maybe to have some input areas for text. Let's investigate how to develop a simple plugin with input text area as input entry point and some new generated classes, based on input text as a result. As a source code example we will have a look at source code based on my pet project that also was used as a development tool in AUTO1 to generate non GraphQl based POJO classes.
\nUSER STORY
\nAs an Android developer I need to interact with backend data. It can be usually presented as JSON data or if we can speak about new and modern practices it also can be presented as a GraphQl scheme. GraphQl is a really powerful framework with its own classes generation framework. But let's go back one step and imagine that we have to do some data presentation classes updated for the project without GraphQl support. To do it, we need to find the target class, compare its fields with new JSON fields and update it. It can be easy if we have only one field changed, but for multiple inner fields and classes with its own inner fields it can be too complicated. We can find some online services to convert JSON to POJO and copy/paste output files, but let's try to integrate this technology to our IDE! And our job will be only to copy/paste new JSON to some window input field! Like this one:
\nTo make it possible, let's think about our problem and try to do small decomposition into logical steps. Lets formulate our goals by imaging simple user stories:
\nAs a user I want to input JSON text into the input field.
\nAs a user I want to transform JSON text into POJO files.
\nAs a user I want to see the result notification.
\nWe will skip JSON to POJO transformation for this article, but we will learn how to develop a plugin with required user interface. Let's think about option number two as about some library that we already have and can use as a part of our small project.
\nTECHNOLOGY STACK
\nBefore we will start let's have a look on basis plugin implementation. There are 2 base options to develop new plugin:
\n\nWe will speak about gradle implementation. Gradle is a really powerful framework and it can be really helpful if we want to simplify our building, releasing and testing. The project structure is a common structure for gradle based projects:
\nmy_gradle_plugin\n\n├── build.gradle\n\n├── gradle\n\n│ └── wrapper\n\n│ ├── gradle-wrapper.jar\n\n│ └── gradle-wrapper.properties\n\n├── gradlew\n\n├── gradlew.bat\n\n├── settings.gradle\n\n└── src\n\n├── main\n\n│ ├── java\n\n│ └── resources\n\n│ └── META-INF\n\n│ └── plugin.xml\n\n└── test\n\n├── java\n\n└── resources\n\n Most important topic for us will be the plugin.xml file. We already discussed some details in the previous article and we can be focused on some UI related topics.
\nDuring the plugin development we can use Java/Kotlin and all utility tools that we want like jUnit testing and dependency injection frameworks. In our current example Koin and JUnit can be found. So, now we have and know about project structure, some utility tools, language to write the code and now we are ready to think how it can be possible to create a user interface and connect it with our IDE. Let's remember about our major goals:
\nGOAL 1 - As a user I want to input JSON text into the input field.\n
\nGOAL 2 - As a user I want to see the result notification.\n
and see how we can implement it.
\nGOAL 1
\nFirst of all, let's learn how to connect our plugin with the IDE user interface. As we can see the IDE has a lot of action groups to do something (create new files for example). According to our idea to have some logic that can help us to convert JSON to POJO it would be great to have a new item in the new file list. It will be something like an action “Create new POJO file”.
\nTo connect our logic with the IDE by following this path we have to remember about the plugin.xml file that was discussed early. We can use this configuration file to describe our plugin and how it can be used.
\nLet's find the actions section and define new action to show our input field dialog view.
\n<actions>\n\n<action id=\"GeneratePOJOAction\" class=\"GeneratePOJOAction\"\n\nicon=\"/icons/pojo.png\"\n\ntext=\"Generate POJO from JSON\"\n\ndescription=\"GeneratePOJOAction\">\n\n<add-to-group group-id=\"NewGroup\" anchor=\"last\"/>\n\n</action>\n\n</actions>As we can see we can use some properties to describe how users will be available to interact with our plugin. We can define a custom icon for our action, define the position inside of the items list (“NewGroup” anchor “last”) and we can define the class to execute when action will be invoked by the user.
\nCustom action class should extend the abstract AnAction class with the implementation of actionPerformed() method.
\nimport com.intellij.openapi.actionSystem.AnAction\n\nimport com.intellij.openapi.actionSystem.AnActionEvent\n\nclass GeneratePOJOAction : AnAction() {\n\noverride fun actionPerformed(e: AnActionEvent) { \n\n//TODO: Add your UI implementation here \n\n} \n}Inside of actionPerformed() method implementation we can add the logic to show a dialog window with the input field for JSON text. To show dialog view we can easily use DialogBuilder from plugin development SDK and Java swing to create a user interface.
\nMore information about actions can be found on the official documentation page.
\nGOAL 2
\nLet's imagine now that we already implemented logic to show the input text dialog with some selectable options to transform this text. We also added some logic of transformation - that can be some library to work with it or maybe our own implementation. And as the result of that transformation some new POJO files were generated added into our project (We can interact directly with the project or we can use project representation, provided by the plugin development SDK).
\nBut what about the next steps? We also need to notify the user about the result: it can be a success result notification, or maybe some error case notification. To implement it we can use default tools, provided by plugin development SDK. We can show some information to the user by using popup, notifications or messages.
\nLet's imagine the following case: we have a text input field and we have some logic to convert/transform the text from this input field. If we can speak about JSON to POJO transformation, we have to understand that any random text cannot be converted to POJO correctly. Target text should satisfy some conditions and also should have the correct JSON structure and it means that we have to not only show some notification if text structure is not valid, but we have to block UI and break our transformation flow.
\nMessages can really help us with it! According to the official documentation:
\nThe Messages class provides a way to show simple message boxes, input dialogs (modal dialogs with a text field), and chooser dialogs (modal dialogs with a combo box). The function of different methods of the class should be clear from their names. When running on macOS, the message boxes shown by the Messages class use the native UI.
\nLets see the following code:
\ncompanion object {\n\nprivate const val BUTTON_TITLE = \"OK\"\n\nprivate const val DEFAULT_OPTION_INDEX = -1\n\nprivate val DEFAULT_ICON = null\n\n}\n\nfun onPluginExceptionHandled(exception: RoboPluginException) {\n\nMessages.showDialog(\n\nexception.message, exception.title,\n\narrayOf(BUTTON_TITLE),\n\nDEFAULT_OPTION_INDEX,\n\nDEFAULT_ICON\n\n)\n\n}As we can see we can use the show dialog method, provided by SDK. We can define some dialog parameters, like title, message, button and of course we can define our custom plugin icon. If the image is not defined, standart Java icon or IDE icon would be shown. More information about images support can be found here. Also as it was already discussed here we can add support for internationalization instead of hardcoding only english string values.
\nAnd as the result we can see this amazing small UI blocking window with our message text:
\nIt looks now that we found a solution to cover the error cases. Now we can prevent users from wrong input and show notification about it. Let's think about the success use case. Let's imagine that the input text was correct and we processed our JSON to POJO transformation as expected. Maybe some new files were generated, maybe it was only one new file. It will be a really good user experience if we can find a possibility to inform our users about it. Maybe one of the possible ways can be to show notification messages. It can be a small popup view with some text, like this one:
\nand maybe we also can print some information to the event log:
\n12:00 Response.java was updated.\n \n12:00 POJO generation: SuccessIt looks now that we are ready to totally satisfy our user story requirements! Let's do the final steps and implement the following code:
\ncompanion object{\n\nprivate const val MESSAGE_SUCCESS = \"POJO generation: Success\"\n\nprivate const val GROUP_ID = \"RoboPOJO Generator\"\n\n}\n\nfun showSuccessMessage() {\n\nshowMessage(\n\nproject = ProjectManager.getInstance().openProjects.first(),\n\nmessage = MESSAGE_SUCCESS,\n\ntype = NotificationType.INFORMATION,\n\n)\n\n}\n\nprivate fun showMessage(\n\nmessage: String, type: NotificationType, project: Project\n\n) = NotificationGroupManager.getInstance()\n\n.getNotificationGroup(GROUP_ID)\n\n.createNotification(message, type)\n\n.notify(project)\n\n As we can see we can use the create notification method, provided by SDK. Unlike dialog related logic, we also have to define the project that we want to use to show the notification. As an example let's get only the first project (most popular use case), but we have to understand that users can open not only one project in the IDE and we have to take care about it too. So, as we can see it is also possible to define message text. Also we can define the message type (it can be INFORMATION, WARNING or ERROR) and we have to take care about the notification group that was defined inside of our plugin.xml file:
\n<extensions defaultExtensionNs=\"com.intellij\">\n\n<notificationGroup id=\"RoboPOJO Generator\"\n\ndisplayType=\"BALLOON\"\n\nkey=\"com.robohorse.robopojogenerator\"/>\n\n</extensions>FEW WORDS AT THE END
\nAs we can see it was not really a big deal to develop some small and hopefully useful tools for daily use or to help your teammates. The major idea is just to understand that integration with IDE can be really simple and when we will finish with it, we can be focused on the functionality of our tool. Perhaps in the future when we will have a stable version with some really cool features we can share our tool not only with teammates that we are working with directly, but maybe it also can be helpful for some developers from some random parts of the world. And maybe together we can simplify our daily job!
","fields":{"slug":"/IntelliJ IDEA plugin development - focus on UI based plugins/","tags":["auto1","engineering","android","mobile","intellij","idea"]}}},{"node":{"id":"a3a21c38-873e-56db-a170-eec0e6136040","frontmatter":{"category":"Coding","title":"Writing IntelliJ plugins","date":"2019-12-10","summary":"How to write a simple IntelliJ plugin","thumbnail":{"relativePath":"pages/intellij-plugin/logo.png","childImageSharp":{"resolutions":{"base64":"data:image/png;base64,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","width":325,"height":325,"src":"/static/b2f976ed5fa752977d8f8f9b2516534c/b3029/logo.png","srcSet":"/static/b2f976ed5fa752977d8f8f9b2516534c/b3029/logo.png 1x,\n/static/b2f976ed5fa752977d8f8f9b2516534c/8d141/logo.png 1.5x,\n/static/b2f976ed5fa752977d8f8f9b2516534c/ee72c/logo.png 2x,\n/static/b2f976ed5fa752977d8f8f9b2516534c/5dfa8/logo.png 3x"}}},"authorName":"Piotr Czekaj","authorDescription":"Piotr is a Senior Software Engineer at AUTO1 Group.","authorAvatar":{"relativePath":"pages/intellij-plugin/avatar.png","childImageSharp":{"resolutions":{"base64":"data:image/png;base64,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","width":50,"height":50,"src":"/static/26a7a327ccc4b335712e5a7086f2b26d/45876/avatar.png","srcSet":"/static/26a7a327ccc4b335712e5a7086f2b26d/45876/avatar.png 1x,\n/static/26a7a327ccc4b335712e5a7086f2b26d/eb85b/avatar.png 1.5x,\n/static/26a7a327ccc4b335712e5a7086f2b26d/4f71c/avatar.png 2x,\n/static/26a7a327ccc4b335712e5a7086f2b26d/9ec3e/avatar.png 3x"}}},"headerImage":{"relativePath":"pages/intellij-plugin/header.png","childImageSharp":{"resolutions":{"base64":"data:image/png;base64,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","width":1280,"height":720,"src":"/static/6fae10ea7503a11a8f308ac2e2a5217a/26421/header.png","srcSet":"/static/6fae10ea7503a11a8f308ac2e2a5217a/26421/header.png 1x"}}}},"html":"During analysis of why some services take a long time to build, several problems have been found, mostly related to number of Spring contexts that were created during integration tests. More about those problems can be found in previous blog post. In order to decrease the likelihood that slow tests will appear at AUTO1, we implemented an IntelliJ plugin which warns a developer about possible problems when he writes code and provides quick fixes if they are applicable.
\n@DirtiesContext annotation which slows tests down because it forces creation of new Spring context@ActiveProfiles (slows tests down because different Spring context would have to be created for each combination)@ActiveProfiles is greater than 3@FeignClient (or DTO used by client) not documented with Swagger annotations@TransactionalDuring the plugin development, we realized that resources on writing IntelliJ plugins are scarce, and therefore decided to create a step by step tutorial on how to implement @DirtiesContext inspection.
In our tutorial we will be using the community edition of IntelliJ 2018.3.5. Final source code is available on github.\nThere are several ways on how to create IntelliJ plugin. The recommended one is to use Intellij plugin for Gradle and that’s what we will use in this tutorial. Let’s start with creating new project using File > New > Project..., select Gradle and make sure that in Additional Libraries and Frameworks both Java and Intellij Platform Plugin are selected.\nIf you cannot see “Gradle” or “Intellij Platform Plugin” then please make sure that both “Gradle” and “Plugin DevKit” IntelliJ plugins are installed.\nContinue next steps of the wizard using default values, use any groupId and artifactId. After some time IntelliJ will download dependencies and create an empty plugin.
\nOur inspection should warn a developer each time there is a class annotated with org.springframework.test.annotation.DirtiesContext and provide quick fix which deletes @DirtiesContext. If Spring is not your thing then any other annotation can be used instead.
There are two kinds of inspections:
\nLocal inspections are executed in the background when file is opened, in general they have access to currently open file. Local inspection cannot report problem for not currently processed file. Inspection class has to extend com.intellij.codeInspection.LocalInspectionTool or one of subclasses.\nGlobal inspections work only in batch mode when analysis is manually triggered via Analyze > Inspect Code and see complete graph of references between classes and can report problem for any file. Inspection class has to extend com.intellij.codeInspection.GlobalInspectionTool or one of subclasses.
We don’t need to access complete graph of references and we would like to give a hint that something is wrong as soon as possible so local inspection is a better choice for our use case. First problem that we encounter is to pick proper base class. One approach is to ask IntelliJ to show class Hierarchy of LocalInspectionTool and take a look what other inspections are extending. In this case AbstractBaseJavaLocalInspectionTool seems to be a good choice since most of Java inspections are based on it.
Create new class named DirtiesContextInspection with following content:
public class DirtiesContextFirstVersionInspection extends AbstractBaseJavaLocalInspectionTool {\n private static final String DIRTIES_CONTEXT = \"org.springframework.test.annotation.DirtiesContext\";\n\n private static final String DESCRIPTION_TEMPLATE = \"Usage of @DirtiesContext makes integration tests slower\";\n\n public String getDisplayName() {\n return \"Usage of @DirtiesContext is not recommended\";\n }\n\n public String getGroupDisplayName() {\n return GroupNames.PERFORMANCE_GROUP_NAME;\n }\n\n public String getShortName() {\n return \"DirtiesContext\";\n }\n\n public boolean isEnabledByDefault() {\n return true;\n }\n\n public PsiElementVisitor buildVisitor(@NotNull final ProblemsHolder holder, \n boolean isOnTheFly) {\n return new JavaElementVisitor() {\n\n public void visitAnnotation(PsiAnnotation annotation) {\n super.visitAnnotation(annotation);\n\n String qualifiedName = annotation.getQualifiedName();\n\n if (DIRTIES_CONTEXT.equals(qualifiedName)) {\n holder.registerProblem(annotation, DESCRIPTION_TEMPLATE);\n }\n }\n };\n }\n}The most interesting thing happens in a visitor which is notified each time a Java annotation is encountered in source code. By overriding different methods, plugin can process methods, classes, imports etc. In our case we check if fully qualified name of annotation matches our expectations and register a problem when that’s the case. Later on we will change this class to include also a quick fix. Creation of inspection class is not enough to make it available in IntelliJ - it’s also needed to register inspection in plugin.xml which among other things describes what plugin does, what other plugins are required and in which version of IntelliJ it can be used.
It’s possible to register each inspection one by one in plugin.xml under extensions tag and configure inspection using xml but we find it easier to register inspectionToolProvider and configure using it in Java code.
Create the following class to implement our inspection provider:
\npublic class CodeInspectionProvider implements InspectionToolProvider {\n public Class[] getInspectionClasses() {\n return new Class[]{\n DirtiesContextInspection.class\n };\n }\n}And register it in plugin.xml:
<extensions defaultExtensionNs=\"com.intellij\">\n <inspectionToolProvider implementation=\"com.auto1.intellij.tutorial.CodeInspectionProvider\"/>\n </extensions>Now it’s time to check our inspection in action by running runIde gradle task. This could be done from terminal by executing ./gradlew runIde but it’s better to use Gradle view in IntelliJ since it allows to start IDE in debug mode (if needed just right click on task and select Debug, you can create run configuration to speed-up in the future). New IntelliJ instance should show up, if you already have sources of some project that uses Spring Boot then open it, otherwise you could create a new project. Annotate some class with @DirtiesContext annotation and observe inspection marker showing up. In case of problems logs can be found at build/idea-sandbox/system/log/.
Many inspections report not only problems but also provide automatic ways of fixing issues. In case of DirtiesContext, it’s not possible to provide safe way of removing it because DirtiesContext is often used when bean holds some state which makes tests dependent on each other. Usually we want to remove the annotation and then figure out the \"dirty parts\" and clean them up in an elegant way. Since the second part is hard to automate we will provide quick fix which only removes annotation.
\nGo back to DirtiesContextInspection class and add quick fix:
private static class DeleteQuickFix implements LocalQuickFix {\n public String getName() {\n return \"Removes usage of @DirtiesContext\";\n }\n\n public void applyFix(@NotNull Project project, @NotNull ProblemDescriptor descriptor) {\n descriptor.getPsiElement().delete();\n }\n\n public String getFamilyName() {\n return getName();\n }\n }Next step is to pass quick fix when problem is registered:
\nholder.registerProblem(annotation, DESCRIPTION_TEMPLATE, new DeleteQuickFix());Executing runIde Gradle task should prove that quick fix works as expected.
Up to this point we have used hardcoded strings inside inspection name and description. To allow the plugin to be accessible in different languages we can externalize the messages. For this purpose we can use properties file. First create PluginBundle class:
public class PluginBundle {\n private static Reference<ResourceBundle> ourBundle;\n\n private static final String BUNDLE = \"com.auto1.intellij.tutorial.PluginBundle\";\n\n private PluginBundle() { }\n\n public static String message(@NotNull @PropertyKey(resourceBundle = BUNDLE) String key, \n @NotNull Object... params) {\n return CommonBundle.message(getBundle(), key, params);\n }\n\n private static ResourceBundle getBundle() {\n ResourceBundle bundle = com.intellij.reference.SoftReference.dereference(ourBundle);\n if (bundle == null) {\n bundle = ResourceBundle.getBundle(BUNDLE);\n ourBundle = new SoftReference<>(bundle);\n }\n return bundle;\n }\n}Then create a new file matching BUNDLE constant, in my case it will be src/main/resources/com/auto1/intellij/tutorial/PluginBundle.properties with content:
inspection.dirties.context.display.name=Usage of @DirtiesContext is not recommended\ninspection.dirties.context.problem.descriptor=Usage of @DirtiesContext makes integration tests slower\ninspection.dirties.context.use.quickfix=Removes usage of @DirtiesContextRegister bundle in plugin.xml:
<resource-bundle>com.auto1.intellij.tutorial.PluginBundle</resource-bundle>And finally use bundle in inspection, for example:
\n public String getDisplayName() {\n return PluginBundle.message(\"inspection.dirties.context.display.name\");\n }We picked LightPlatformCodeInsightFixtureTestCase as base for our tests because it is recommended in the documentation. Unfortunately, testing appeared harder to set up properly than expected.
First problem was that our tests couldn’t see classes from JDK, which was fixed by specifying project descriptor to use internal JDK:
\n protected LightProjectDescriptor getProjectDescriptor() {\n return new LightProjectDescriptor() {\n public Sdk getSdk() {\n return JavaAwareProjectJdkTableImpl.getInstanceEx().getInternalJdk();\n }\n };\n }Second problem was that visitor received incorrect fully qualified class name of the annotation. Instead of org.springframework.test.annotation.DirtiesContext, it got DirtiesContext while it worked fine for real project in IDE. It turns out that such behaviour occurs when test project doesn’t see definition of some class. This is fixable by either hardcoding problematic class into test or by adding dependency as library to the project. Second approach avoids copying source code from other projects and seems to be more interesting so it will be presented here. In order to download dependency jar we use ShrinkWrap library:
private File[] getMavenArtifacts(String... mavenArtifacts) {\n File[] files = Maven.resolver()\n .resolve(mavenArtifacts)\n .withoutTransitivity()\n .asFile();\n if (files.length == 0) {\n throw new IllegalArgumentException(\"Failed to resolve artifacts \" + Arrays.toString(mavenArtifacts));\n }\n return files;\n }When dependency is resolved and downloaded into local Maven cache it can be added as library with code listed below:
\n protected void attachMavenLibrary(String mavenArtifact) {\n File[] jars = getMavenArtifacts(mavenArtifact);\n Arrays.stream(jars).forEach(jar -> {\n String name = jar.getName();\n PsiTestUtil.addLibrary(myFixture.getProjectDisposable(), myModule, name, jar.getParent(), name);\n });\n }It’s important to use myFixture.getProjectDisposable() instead of myFixture.getProject() otherwise there is an exception during test shutdown:
com.intellij.openapi.util.TraceableDisposable$DisposalException: Virtual pointer 'jar:///somePath/.m2/repository/org/springframework/spring-test/5.1.5.RELEASE/spring-test-5.1.5.RELEASE.jar!/' hasn't been disposedNext surprise is that by default test searches for test data in strange location inside IntelliJ home folder which can be fixed with overriding getTestDataPath. Since input files most likely won’t compile because of missing imports and possible usage of special markers like src/test/java folder to store them:
@Override\n protected String getTestDataPath() {\n return \"src/test/testData\";\n }Inspection tests can be done by providing file to analyse and resulting file that should be created after given quick fix has been applied. Inspection tests use configureByFile to load input file, doHighlighting to trigger source code analysis, launchAction to execute quick fix and finally checkResultByFile to compare results against after file.
myFixture.configureByFile(testName + \".java\");\n myFixture.enableInspections(new DirtiesContextInspection());\n myFixture.doHighlighting();\n IntentionAction quickFixAction = myFixture.findSingleIntention(intentionHint);\n myFixture.launchAction(quickFixAction);\n myFixture.checkResultByFile(testName + \".after.java\");Complete source code can be found at github github
\nIf you would like to share your plugin with other developers, you can publish to JetBrains plugin repository as described in the documentation. Other simple option is to execute buildPlugin Gradle task which will create plugin zip file inside build/distributions and then install it via Install Plugin from disk... available inside Preferences > Plugins (in IntelliJ 2018.3 is available through \"gears icon\").
\nWhen working on your own ideas you might run into a situation when you don't know how to implement some functionality. In this situation you could try to find the answer using links provided in section below. What also worked for us was reading source code of inspections available as part of community edition of IntelliJ, often there is an existing inspection which does a similar thing to what you might want to do.
\n