Java: Store Java modules in RefJavaManager for the inspection "Unused 'requires' statement in module-info" (IDEA-163139)

java/java-analysis-api/src/com/intellij/codeInspection/reference/RefJavaManager.java

@@ -54,6 +54,8 @@ public abstract class RefJavaManager implements RefManagerExtension<RefJavaManag
    */
   public abstract RefPackage getPackage(String packageName);
 
+  public abstract RefEntity getRefJavaModule(String name);
+
   /**
    * Creates (if necessary) and returns the reference graph node for the specified PSI parameter.
    *

java/java-analysis-impl/src/com/intellij/codeInspection/java19modules/Java9UnusedRequiresStatementInspection.java

@@ -121,9 +121,12 @@ public class Java9UnusedRequiresStatementInspection extends GlobalJavaBatchInspe
   @Nullable
   private static JavaModuleInfo getJavaModuleInfo(@NotNull RefModule refModule, boolean addIfMissing) {
     Optional<JavaModuleInfo> optionalInfo = refModule.getUserData(JAVA_MODULE_INFO);
+    if (!addIfMissing) {
+      return optionalInfo != null ? optionalInfo.orElse(null) : null;
+    }
     if (optionalInfo == null) {
       optionalInfo = Optional
-        .ofNullable(addIfMissing ? refModule : null)
+        .of(refModule)
         .map(RefModule::getModule)
         .map(JavaModuleGraphUtil::findDescriptorByModule)
         .map(JavaModuleInfo::new);
@@ -242,7 +245,7 @@ public class Java9UnusedRequiresStatementInspection extends GlobalJavaBatchInspe
     }
   }
 
-  private static class JavaModuleInfo {
+  private static class JavaModuleInfo { // TODO: remove this
     private final PsiJavaModule javaModule;
     private final Set<String> importedPackageNames;
 

java/java-analysis-impl/src/com/intellij/codeInspection/reference/RefJavaManagerImpl.java

@@ -28,6 +28,7 @@ import com.intellij.openapi.util.Comparing;
 import com.intellij.openapi.util.Disposer;
 import com.intellij.openapi.vfs.VirtualFile;
 import com.intellij.psi.*;
+import com.intellij.psi.impl.file.impl.JavaFileManager;
 import com.intellij.psi.javadoc.PsiDocComment;
 import com.intellij.psi.javadoc.PsiDocTag;
 import com.intellij.psi.search.GlobalSearchScope;
@@ -40,6 +41,7 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import javax.swing.*;
+import java.util.Collection;
 
 
 /**
@@ -55,6 +57,7 @@ public class RefJavaManagerImpl extends RefJavaManager {
   private PsiClass myServlet;
   private RefPackage myDefaultPackage;
   private THashMap<String, RefPackage> myPackages;
+  private THashMap<String, RefJavaModule> myJavaModules;
   private final RefManagerImpl myRefManager;
   private PsiElementVisitor myProjectIterator;
   private EntryPointsManager myEntryPointsManager;
@@ -109,6 +112,24 @@ public class RefJavaManagerImpl extends RefJavaManager {
     return refPackage;
   }
 
+  @Override
+  public RefEntity getRefJavaModule(String name) {
+    if (myJavaModules == null) {
+      myJavaModules = new THashMap<>();
+    }
+    RefJavaModule refJavaModule = myJavaModules.get(name);
+    if (refJavaModule == null) {
+      Project project = myRefManager.getProject();
+      GlobalSearchScope scope = GlobalSearchScope.projectScope(project);
+      Collection<PsiJavaModule> javaModules = JavaFileManager.SERVICE.getInstance(project).findModules(name, scope);
+      if (javaModules.size() == 1) {
+        PsiJavaModule javaModule = javaModules.iterator().next();
+        refJavaModule = new RefJavaModuleImpl(javaModule, myRefManager);
+        myJavaModules.put(name, refJavaModule);
+      }
+    }
+    return refJavaModule;
+  }
 
   public boolean isEntryPoint(final RefElement element) {
     UnusedDeclarationInspectionBase tool = getDeadCodeTool(element);
@@ -279,6 +300,9 @@ public class RefJavaManagerImpl extends RefJavaManager {
     else if (PACKAGE.equals(type)) {
       return RefPackageImpl.packageFromFQName(myRefManager, fqName);
     }
+    else if (JAVA_MODULE.equals(type)) {
+      return RefJavaModuleImpl.javaModuleFromExternalName(myRefManager, fqName);
+    }
     return null;
   }
 

java/java-analysis-impl/src/com/intellij/codeInspection/reference/RefJavaModuleImpl.java

@@ -117,6 +117,7 @@ public class RefJavaModuleImpl extends RefElementImpl implements RefJavaModule {
           }
         }
       }
+      ((RefModuleImpl)myRefModule).add(this);
       getRefManager().fireBuildReferences(this);
     }
   }
@@ -139,4 +140,8 @@ public class RefJavaModuleImpl extends RefElementImpl implements RefJavaModule {
     }
     return resolvedElements.size() == 1 ? resolvedElements.get(0) : null;
   }
+
+  static RefEntity javaModuleFromExternalName(RefManagerImpl manager, String name) {
+    return manager.getExtension(RefJavaManager.MANAGER).getRefJavaModule(name);
+  }
 }