Debugger cannot see local variable in a Lambda - intellij-idea

I noticed that when I hover my mouse over a local variable when my debugger is stopped inside a lambda it will report Cannot find local variable 'variable_name' even if it's visible inside the lambda and it's used.
Example code
public class Main {
public static void main(String[] args) {
String a = "hello_world";
m1(a);
}
private static void m1(String a) {
AccessController.doPrivileged((PrivilegedAction<String>) () -> {
System.out.println("blala " + a);
return "abc";
});
}
}
Try with a breakpoint in System.out.println("blala " + a); and after return "abc" and it always report the same error.
I used AccessController.doPrivileged because it's what I used in my original code and of course i'm using Java 8.
It says the same thing in Watchers and Evaluate Expression.
I tried using the "anonymous class" version and the debugger sees the value of a correctly
private static void m1(String a) {
AccessController.doPrivileged(new PrivilegedAction<String>() {
#Override
public String run() {
System.out.println("blala " + a);
return "abc";
}
});
}
I'm missing something about lambda expressions or it's an IntellIJ IDEA 14 bug?
I don't want to report the bug right now because I already reported a bug that was caused by my code instead of IntellIJ IDEA, so I want to be sure before do something (and because I don't use Java 8 so often, so I could be wrong).

This appears to be a know issue. According to JetBrains the root causes of this behavior is with the JDK. For more info see: IDEA-126257

I can confirm what is written in IDEA bug report linked by Mike Rylander: this is a JDK bug and update to version 8u60_25 of the JDK solves it.

Related

Executing an unused lambda expression in debug session throws ClassNotFoundException

This is a bit nitpicky- I wonder if it's a bug or a feature:
I have this main in Intellij:
public static void main(String[] args) throws InterruptedException {
Comparator<String> comp = (s1,s2) -> 1;
System.out.println("Break here");
}
When I debug and break at the "System.out.." I see that comp is initialized. However, when I try to execute it from "Expression Evaluation" window I get a ClassNotFoundException!
Of course evaluating the same thing in code works perfectly. Is it somehow related to the way lambdas are implemented under the hood or just a bug in the IDE?
I am using Intellij 13.1.4.
Evaluation of Lambda expressions is supported only starting from version 14.
Taken from What's New in IntelliJ IDEA 14 page:

Getting Tab parameters inside LaunchConfigurationDelegate

I have a custom launch configuration. It currently has a JavaArgumentsTab() where I can enter things for VM arguments and Program arguments. But how do I actually get any values entered there?
Ideally I would get them inside my LaunchConfigurationDelegate's launch() method. I expected to find any text entered as arguments inside the LaunchConfiguration or other parameters to that method, and I'm sure this is a newbie question, but I really haven't found anything promising.
TabGroup:
public class LaunchConfigurationTabGroup extends AbstractLaunchConfigurationTabGroup {
#Override
public void createTabs(ILaunchConfigurationDialog dialog, String mode) {
ILaunchConfigurationTab[] tabs = new ILaunchConfigurationTab[] {
new JavaArgumentsTab(),
new CommonTab()
};
setTabs(tabs);
} }
LaunchConfigurationDelegate:
public class LaunchConfigurationDelegate implements ILaunchConfigurationDelegate {
#Override
public void launch(ILaunchConfiguration configuration, String mode,
ILaunch launch, IProgressMonitor monitor) throws CoreException {
// How to get anything entered on my Java tab here...?
} }
Everything from the tabs should already have been set as attribute values in the ILaunchConfiguration when launch is called.
The settings from JavaArgumentsTab are stored in the attributes using constants from IJavaLaunchConfigurationConstants.

Rename "params" parameter in Java Bindings Library with Mono for Android?

I'm trying to create a Java Binding Library for BugSense, but one of the methods has a parameter named "params" which is a reserved word in C#. I've tried to use the Metadata.xml file to rename it, but I can't figure out how to access the class, let alone the method or it's parameter.
Here is the problem code it's generating:
namespace Com.Bugsense.Trace {
[global::Android.Runtime.Register ("com/bugsense/trace/ActivityAsyncTask", DoNotGenerateAcw=true)]
internal partial class ActivityAsyncTaskInvoker : ActivityAsyncTask {
static IntPtr id_doInBackground_arrayLjava_lang_Object_;
[Register ("doInBackground", "([Ljava/lang/Object;)Ljava/lang/Object;", "GetDoInBackground_arrayLjava_lang_Object_Handler")]
protected override global::Java.Lang.Object DoInBackground (global::Java.Lang.Object[] params)
{
if (id_doInBackground_arrayLjava_lang_Object_ == IntPtr.Zero)
id_doInBackground_arrayLjava_lang_Object_ = JNIEnv.GetMethodID (class_ref, "doInBackground", "([Ljava/lang/Object;)Ljava/lang/Object;");
IntPtr native_params = JNIEnv.NewArray (params);
global::Java.Lang.Object __ret = Java.Lang.Object.GetObject<global::Java.Lang.Object> (JNIEnv.CallObjectMethod (Handle, id_doInBackground_arrayLjava_lang_Object_, new JValue (native_params)), JniHandleOwnership.TransferLocalRef);
if (params != null) {
JNIEnv.CopyArray (native_params, params);
JNIEnv.DeleteLocalRef (native_params);
}
return __ret;
}
}
}
Here is my mapping, which I feel should work, but just refuses to.
<attr path="/api/package[#name='com.bugsense.trace']/class[#name='ActivityAsyncTaskInvoker']/method[#name='doInBackground']/parameter[#name='params']" name="managedName">#params</attr>
I've tried everything I can think of. Please, HELP!
So, turns out it's just a bug in the current version of Mono for Android. If you update to the 4.2.4 build, which is in beta, everything compiles fine.

Can't find system.out.println()

I created a project, it asked me to select JDK version and finish.
I couldn't find system namespace in autocomplete.
I typed it manually but IDEA told me that system doesn't exist.
It's System (with a cap)
Some very useful shortcuts:
soutm (+TAB) ==> System.out.println("Class.And.Method.Name")
soutv (+TAB) ==> System.out.println("Last variable used = " + value);
sout (+TAB) ==> System.out.println();
I really love IntelliJ. Glad I moved to it from Eclipse a couple of years ago ;)
Just type sout.
public class Main {
public static void main(String[] args) {
int data = 1;
System.out.println(); ===>sout
System.out.println("Main.main"); ===>soutm
System.out.println("args = [" + args + "]"); ===>soutp
System.out.println("data = " + data); ===>soutv
}
}
sout - just print System.out.println()
soutm - added Class name & method name
soutp - added parameter
soutv - added last variable name
We can change the auto complete settings to to ignore case. Go to:
File -> Settings... -> IDE Settings -> Editor -> Code Completion
and change 'Case sensitive completion' to 'None'.
I came from eclipse and was using the syso shortcut, so I have just added it to my live template. Here is a templete:
System.out.println($END$);
Here is a screenshot:
Don't forget to add Java as applicable context (at the bottom of the window).
Now it will appear as a hint while you typing syso here is a screenshot:
Hope it helps
This can also happen because user has not created any main function or trying to test this directly in class without any function

How do I sense if my unit test is a member of an ordered test and, if it is, which position in that ordered test it is at?

Environment:
I have a program - named CSIS - which I need to run a lot of automated tests on in Visual Studio 2010 using C#. I have a series of functions which need to be run in many different orders but which all start and end at the same 'home screen' of CSIS. The tests will either be run on their own as a single CodedUITest (.cs filetype) or as an ordered test (.orderedtest filetype).
Goal:
The goal is to open to the CSIS homepage once no matter which of the unit tests is run first and then, after all CodedUITests are finished, no matter which unit test is last, the automated test will close CSIS. I don't want to create a separate unit test to open CSIS to the homepage and another to close CSIS as this is very inconvenient for testers to use.
Current Solution Development:
UPDATE: The new big question is how do I get '[ClassInitialize]' to work?
Additional Thoughts:
UPDATE: I now just need ClassInitialize to execute code at the beginning and ClassCleanUp to execute code at the end of a test set.
If you would like the actual code let me know.
Research Update:
Because of Izcd's answer I was able to more accurately research the answer to my own question. I've found an answer online to my problem.
Unfortunately, I don't understand how to implement it in my code. I pasted the code as shown below in the 'Code' section of this question and the test runs fine except that it executes the OpenWindow() and CloseWindow() functions after each test instead of around the whole test set. So ultimately the code does nothing new. How do I fix this?
static private UIMap sharedTest = new UIMap();
[ClassInitialize]
static public void ClassInit(TestContext context)
{
Playback.Initialize();
try
{
sharedTest.OpenCustomerKeeper();
}
finally
{
Playback.Cleanup();
}
}
=====================================================================================
Code
namespace CSIS_TEST
{
//a ton of 'using' statements are here
public partial class UIMap
{
#region Class Initializization and Cleanup
static private UIMap sharedTest = new UIMap();
[ClassInitialize]
static public void ClassInit(TestContext context)
{
Playback.Initialize();
try
{
sharedTest.OpenWindow();
}
finally
{
Playback.Cleanup();
}
}
[ClassCleanup]
static public void ClassCleanup()
{
Playback.Initialize();
try
{
sharedTest.CloseWindow();
}
finally
{
Playback.Cleanup();
}
}
#endregion
Microsoft's unit testing framework includes ClassInitialise and ClassCleanUp attributes which can be used to indicate methods that execute functionality before and after a test run.
( http://msdn.microsoft.com/en-us/library/ms182517.aspx )
Rather than try and make the unit tests aware of their position, I would suggest it might be better to embed the opening and closing logic of the home screen within the aforementioned ClassInitialise and ClassCleanUp marked methods.
I figured out the answer after a very long process of asking questions on StackOverflow, Googling, and just screwing around with the code.
The answer is to use AssemblyInitialize and AssemblyCleanup and to write the code for them inside the DatabaseSetup.cs file which should be auto-generated in your project. You should find that there already is a AssemblyInitialize function in here but it is very basic and there is no AssemblyCleanup after it. All you need to do is create a static copy of your UIMap and use it inside the AssemblyInitialize to run your OpenWindow() code.
Copy the format of the AssemblyInitialize function to create an AssemblyCleanup function and add your CloseWindow() function.
Make sure your Open/CloseWindow functions only contains basic code (such as Process.Start/Kill) as any complex variables such as forms have been cleaned up already and won't work.
Here is the code in my DatabaseSetup.cs:
using System.Data;
using System.Data.Common;
using System.Configuration;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Microsoft.Data.Schema.UnitTesting;
using System.Windows.Input;
using Keyboard = Microsoft.VisualStudio.TestTools.UITesting.Keyboard;
using Mouse = Microsoft.VisualStudio.TestTools.UITesting.Mouse;
using MouseButtons = System.Windows.Forms.MouseButtons;
namespace CSIS_TEST
{
[TestClass()]
public class DatabaseSetup
{
static private UIMap uIMap = new UIMap();
static int count = 0;
[AssemblyInitialize()]
public static void InitializeAssembly(TestContext ctx)
{
DatabaseTestClass.TestService.DeployDatabaseProject();
DatabaseTestClass.TestService.GenerateData();
if(count < 1)
uIMap.OpenWindow();
count++;
}
[AssemblyCleanup()]
public static void InitializeAssembly()
{
uIMap.CloseWindow();
}
}
}