I am using Java 1.8.0_144, Eclipse (Oxygen) and RunJettyRun plugin on Windows to test my web application. When I modify the Java code in a non-static method (not change to the method signature or adding a new method), the change does not get reflected unless I shut down and resart RunJettyRun. I did some configuration as shown below, but it was not working.
How can I see code change effective without shutting down RunJettyRun?
Related
I am trying to provide an HttpClient from the outside to my ktor server so that I can mock external services and write tests, however I get this exception when I run my test:
Please make sure that you use unique name for the plugin and don't install it twice. Conflicting application plugin is already installed with the same key as `Compression`
io.ktor.server.application.DuplicatePluginException: Please make sure that you use unique name for the plugin and don't install it twice. Conflicting application plugin is already installed with the same key as `Compression`
at app//io.ktor.server.application.ApplicationPluginKt.install(ApplicationPlugin.kt:112)
at app//com.example.plugins.HTTPKt.configureHTTP(HTTP.kt:13)
at app//com.example.ApplicationKt.module(Application.kt:14)
at app//com.example.ApplicationTest$expected to work$1$1.invoke(ApplicationTest.kt:39)
at app//com.example.ApplicationTest$expected to work$1$1.invoke(ApplicationTest.kt:38)
and thats a bit unexpected to me because I am not applying the Compression plugin twice as far as I can tell. If I run the server normally and manually call my endpoint with curl then it works as expected. What am I doing wrong?
I added a runnable sample project here with a failing test.
sample project
official ktor-documentation-sample project.
The problem is that you have the application.conf file and by default, the testApplication function tries to load modules which are enumerated there. Since you also explicitly load them in the application {} block the DuplicatePluginException occurs. To solve your problem you can explicitly load an empty configuration instead of the default one:
// ...
application {
module(client)
}
environment {
config = MapApplicationConfig()
}
// ...
A related problem: Get the class path from the context class loader (of WebLogic for instance)
This is already solved in How to set up the context class loader's classpath for runtime compilation?.
Current problem: Get the same (proper) class path used to run a web app
Reflectively calling the "getClassPath()" method works but it returns a dirty classpath containing unanted modules from $ORACLE_HOME/oracle_common/modules directory.
Problematic scenario:
Deploy a web app "Parent" in WebLogic // <- works
Get the context class path (it's a String object) by reflexively calling "getClassPath()" // <- works
Fork a process out of the main "Parent" process and run it using the context class path // <- fails
04:36:45,238 [Thread-41] ERROR ChildProcess - Exception in thread "main" java.lang.NoSuchMethodError: com.fasterxml.jackson.databind.ObjectMapp
er.configOverride(Ljava/lang/Class;)Lcom/fasterxml/jackson/databind/cfg/MutableConfigOverride;
Explanation
While the context class path contains the necessary dependencies for the child process to run, they are overshadowed by WebLogic's own dependencies. The result is runtime failures such as the one shown above.
Workaround
a) Use a new version of WebLogic server that hopefully would use newer versions of the artifacts needed by the child process // risky endeavour
b) Manually process the context class path and remove any artifact that would shadow their more-recent counterparts
Solution b) looks more practical, but I don't like it for meany reasons:
The reflexive call to "getClassPath" returns a String, and looking for artifact's names in Strings feels frail and weak
I wouldn't know what shadows what. WebLogic prepends its weird artifacts at the start of the string before listing the web app's own dependencies.
Only weblogic.xml has info on the web app's package preferences. I wish I could mimic how WebLogic processes this file to run the web app (Parent) and use that to properly run the child process
It seems to me that forking a process out from a web app running in WebLogic does not enjoy the same package preferences expressed in "weblogic.xml" that the web app (Parent) enjoyed when it was deployed and started running.
Other than the above suggestions, I am welcoming of any stronger solutions
I'm trying to write tests for my addon, but encountering some weird behaviour.
I have created a service (via ember-cli generate), which is used inside a component.
When an actual application is running everything is working fine.
However, when testing the component I get an error saying that the service is undefined when trying to access any of its properties/methods.
In the test i've put the service in "needs" like so:
needs: ['service:my-service']
"Needing" other components (e.g. child ones used inside) works as expected, services strangely fail.
Are there any additional steps that need to be done?
Running ember-cli 0.1.12.
When you generate a service, it also generates an initializer whose job it is to inject the service into the various places that you need it.
So, when you run acceptance tests your app will have booted and initializers will have been run, therefore the services will be available.
However, when unit testing components you get a clean container (better for testing). You just need to inject what you need:
moduleForComponent('foo-bar', null, {
setup: function(container) {
container.register('service:foo', FooService);
container.injection('component', 'fooService', 'service:foo');
}
});
I managed to get this working by using the new Ember.inject API available in the latest (as of writing) 1.10 release.
Apparently the new inject API is intended to replace needs in the future, it also works great with unit tests.
We just managed to get one working using needs: ['service:myService'] instead of needs: ['service:my-service'].
I'm using play application (using Play version 2.1.0) with RabbitMQ and do not have any view component.
So i would like to invoke this play application without hitting the execution URL (http://localhost:9000/<routing_info>) on server startup.
Would also like to know if there is any way in Play 2.1.0 version to run the application on server startup, i mean bootstrapping. Is this option available in play 2.1.0.
As i've read through the documentation its mentioned only for 1.2 version.
Please help!!
Play allows you to define a 'global' object which will be instantiated automatically by Play when the application starts.
In application.conf you should find the following:
# Global object class
# ~~~~~
# Define the Global object class for this application.
# Default to Global in the root package.
application.global=global.Global
On a new play application, this line is commented out. I've uncommented it and made it point to an object called Global in the global package. You can make it what ever you want.
Your global object should extend GlobalSettings.
In my applications, I use a static initialiser block to run code when that class is loaded:
public class Global extends GlobalSettings
{
static
{
...
}
}
I have a small application that uses the Attach API to modify some third party classes during runtime. Alas, I have run into a large problem: the Attach API only comes with the JDK. The necessary files I can copy from the JDK and add into my project, but the library responsible for this(attach.(dll|so)) I can't. This is because I would have to copy attach.lib from a resource inside jar, and put it in the JRE/lib directory.
An action that would not work if the user isn't root on a Linux machine, therefore losing compatibility to alot of users (as this app is supposed to run on a server, and most servers are Linux, and I can't be sure all are root)
I looked into all the classes responsible for the attach API (VirtualMachine, AttachProvider etc) but found no place where it is loading the library.
Is it possible to do this? I mean, can I use the Attach API outside of a JDK installation? If so, how?
You can do so by modifying java.library.path:
static void addToLibPath(String path) throws NoSuchFieldException,
SecurityException,
IllegalArgumentException,
IllegalAccessException
{
if (System.getProperty("java.library.path") != null) {
// If java.library.path is not empty, we will prepend our path
// Note that path.separator is ; on Windows and : on Unix-like,
// so we can't hard code it.
System.setProperty("java.library.path",
path + System.getProperty("path.separator")
+ System.getProperty("java.library.path"));
} else {
System.setProperty("java.library.path", path);
}
// Important: java.library.path is cached
// We will be using reflection to clear the cache
Field fieldSysPath = ClassLoader.class.getDeclaredField("sys_paths");
fieldSysPath.setAccessible(true);
fieldSysPath.set(null, null);
}
Call addToLibPath("path") will add "path" to java.library.path.
Please note that java.library.path is cached, and reflection is required to clear the cache.
As far as I know, you need to run the application looking to do the "attach" from within a JDK (not a JRE). By doing this, you don't need to worry about providing the Attach API or its dependencies - as they are all provided for and managed by the JDK. That said, you shouldn't have any "root" concerns with doing this - as you can extract and run/use a JDK as any user (it doesn't have to be installed / executed as "root"). That said, you'll just need to ensure that your program doing the attaching and the program being attached to are running as the same OS user as to not run into security restrictions.
Our experience is that there is no reliable way to use the attach API without a full JDK. This was particularly acute on Windows. You might get it to work, but you might want to look into plain old JMX instead.