Array index out of bounds exception on FindDeadLocalStores

[miguel-vila]

I'm getting this error when running spotbugs:

The following errors occurred during analysis:
  Exception analyzing BaseUrl using detector edu.umd.cs.findbugs.detect.FindDeadLocalStores
    java.lang.ArrayIndexOutOfBoundsException: Index 5 out of bounds for length 5
      At edu.umd.cs.findbugs.BugCounts.addError(PackageStats.java:50)
      At edu.umd.cs.findbugs.PackageStats.addError(PackageStats.java:240)
      At edu.umd.cs.findbugs.ProjectStats.addBug(ProjectStats.java:273)
      At edu.umd.cs.findbugs.SortedBugCollection.add(SortedBugCollection.java:960)
      At edu.umd.cs.findbugs.SortedBugCollection.add(SortedBugCollection.java:227)
      At edu.umd.cs.findbugs.BugCollectionBugReporter.doReportBug(BugCollectionBugReporter.java:110)
      At edu.umd.cs.findbugs.AbstractBugReporter.reportBug(AbstractBugReporter.java:179)
      At edu.umd.cs.findbugs.DelegatingBugReporter.reportBug(DelegatingBugReporter.java:69)
      At edu.umd.cs.findbugs.FilterBugReporter.reportBug(FilterBugReporter.java:49)
      At edu.umd.cs.findbugs.FilterBugReporter.reportBug(FilterBugReporter.java:49)
      At edu.umd.cs.findbugs.BugAccumulator.reportBug(BugAccumulator.java:199)
      At edu.umd.cs.findbugs.BugAccumulator.reportAccumulatedBugs(BugAccumulator.java:180)
      At edu.umd.cs.findbugs.detect.FindDeadLocalStores.analyzeMethod(FindDeadLocalStores.java:647)
      At edu.umd.cs.findbugs.detect.FindDeadLocalStores.visitClassContext(FindDeadLocalStores.java:198)
      At edu.umd.cs.findbugs.DetectorToDetector2Adapter.visitClass(DetectorToDetector2Adapter.java:76)
      At edu.umd.cs.findbugs.FindBugs2.lambda$analyzeApplication$1(FindBugs2.java:1108)
      At java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
      At edu.umd.cs.findbugs.CurrentThreadExecutorService.execute(CurrentThreadExecutorService.java:86)
      At java.base/java.util.concurrent.AbstractExecutorService.invokeAll(AbstractExecutorService.java:247)
      At edu.umd.cs.findbugs.FindBugs2.analyzeApplication(FindBugs2.java:1118)
      At edu.umd.cs.findbugs.FindBugs2.execute(FindBugs2.java:309)
      At com.siriusxm.sbt.library.SxmJavaSpotBugsPlugin$.$anonfun$projectSettings$5(SxmJavaSpotBugsPlugin.scala:71)
      At com.siriusxm.sbt.library.SxmJavaSpotBugsPlugin$.$anonfun$projectSettings$5$adapted(SxmJavaSpotBugsPlugin.scala:39)
      At scala.Function1.$anonfun$compose$1(Function1.scala:49)
      At sbt.internal.util.$tilde$greater.$anonfun$$u2219$1(TypeFunctions.scala:63)
      At sbt.std.Transform$$anon$4.work(Transform.scala:69)
      At sbt.Execute.$anonfun$submit$2(Execute.scala:283)
      At sbt.internal.util.ErrorHandling$.wideConvert(ErrorHandling.scala:24)
      At sbt.Execute.work(Execute.scala:292)
      At sbt.Execute.$anonfun$submit$1(Execute.scala:283)
      At sbt.ConcurrentRestrictions$$anon$4.$anonfun$submitValid$1(ConcurrentRestrictions.scala:265)
      At sbt.CompletionService$$anon$2.call(CompletionService.scala:65)
      At java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
      At java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:539)
      At java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
      At java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1136)
      At java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
      At java.base/java.lang.Thread.run(Thread.java:833)

the contents of the class are:

import io.vavr.control.Validation;
import java.net.MalformedURLException;
import java.net.URISyntaxException;
import java.net.URL;
import java.util.Optional;

public class BaseUrl {
  public final String value;

  private BaseUrl(String value) {
    this.value = value;
  }

  public static Validation<String, Optional<BaseUrl>> fromString(String value) {
    if (value.isEmpty()) {
      return Validation.valid(Optional.empty());
    } else {
      if (isValidUrl(value)) {
        return Validation.valid(Optional.of(new BaseUrl(value)));
      } else {
        return Validation.invalid(
            "baseUrl '"
                + value
                + "' doesn't match expected format (must be a valid URL with env/region variables)");
      }
    }
  }

  private static String replace(String value) {
    return value.replace("${region}", "region").replace("${env}", "env");
  }

  private static Boolean isValidUrl(String value) {
    try {
      new URL(replace(value)).toURI();
      return true;
    } catch (MalformedURLException e) {
      return false;
    } catch (URISyntaxException e) {
      return false;
    }
  }

  @Override
  public boolean equals(Object other) {
    if (this == other) {
      return true;
    }
    if (other == null || getClass() != other.getClass()) {
      return false;
    }
    BaseUrl baseUrl = (BaseUrl) other;
    return value.equals(baseUrl.value);
  }

  @Override
  public int hashCode() {
    return value.hashCode();
  }
}

I've tried reproducing it in a test (had to remove the io.vavr import) but it succeeds. I have other files in which the same error raises but they are a bit more complex, I could try minimizing them.

version 4.8.5

[welcome]

Thanks for opening your first issue here! 😃
Please check our contributing guideline. Especially when you report a problem, make sure you share a Minimal, Complete, and Verifiable example to reproduce it in this issue.

[hazendaz]

Which version of spotbugs are you using?

[miguel-vila]

4.8.5

[miguel-vila]

I enabled fdls.debug and got this:

    Analyzing method BaseUrl.isValidUrl
    Store at 39@20 is dead
Previous is:   19: areturn[176](1)
BaseUrl.java : isValidUrl
priority: 5
Reporting DLS: Dead store to local variable
{   A_LITTLE_BIT_LOWER_PRIORITY edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.NO_LOADS      true
  FALSE_POSITIVE        edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.EXCEPTION_HANDLER     true
  NO_ADJUSTMENT edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.LOCAL_NAME    ?
}

    Store at 41@26 is dead
Previous is:   25: areturn[176](1)
BaseUrl.java : isValidUrl
priority: 5
Reporting DLS: Dead store to local variable
{   A_LITTLE_BIT_LOWER_PRIORITY edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.NO_LOADS      true
  FALSE_POSITIVE        edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.EXCEPTION_HANDLER     true
  NO_ADJUSTMENT edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.LOCAL_NAME    ?
}

this is pointing to this line: new URL(replace(value)).toURI();. I tried reproducing this through a test but it seems no DLS_DEAD_LOCAL_STORE bug is being reported so maybe I'm not setting up the test correctly.

I got another class that are also throwing the same error, but the method that's failing looks something like:

public Deserializer(Format format) {
  super(Instant.class);
  this.format = format;
}

(this is a class constructor)

[gtoison]

What's SxmJavaSpotBugsPlugin?
It looks to me that it is running SpotBugs and possibly tweaking the edu.umd.cs.findbugs.detect.DeadLocalStoreProperty.NO_LOADS property to A_LITTLE_BIT_LOWER_PRIORITY in some unexpected way

[miguel-vila]

That's an internal SBT plugin that we developed in order to use spotbugs to check sbt modules. I don't think it's intentionally overriding anything. This is the source code: https://gist.github.com/miguel-vila/e96efe3af7eaa1f687104e8c8eaabd62

This is the setup code: https://gist.github.com/miguel-vila/e96efe3af7eaa1f687104e8c8eaabd62#file-sxmjavaspotbugsplugin-scala-L53-L75 which for the most part is just initializing things with defaults.

I'm running it with these parameters:

    spotbugsPriorityThreshold := PriorityThreshold.Normal,
    spotbugsRelaxed := true,

[gtoison]

Thanks for clarifying, would you know why you're setting spotbugsRelaxed ?
I vaguely remember seeing similar issues with that and to be honest I'm not sure what it does

[gtoison]

See #2269 and #943
These two issues seem to be the same problem