Revert "Java: Add CompilationUnit.getATypeAvailableBySimpleName()"

This reverts commit 431aa2c.

Author: atorralba

java/ql/lib/change-notes/2022-09-20-CompilationUnit-simple-name-type.md

@@ -31,50 +31,5 @@ class CompilationUnit extends Element, File {
    */
   Module getModule() { cumodule(this, result) }
 
-  /**
-   * Gets a type which is available by its simple name in this compilation unit.
-   * Reasons for this can be:
-   * - The type is declared in this compilation unit as top-level type
-   * - The type is imported
-   * - The type is declared in the same package as this compilation unit
-   * - The type is declared in the package `java.lang`
-   */
-  ClassOrInterface getATypeAvailableBySimpleName() {
-    // See "Shadowing", https://docs.oracle.com/javase/specs/jls/se17/html/jls-6.html#jls-6.4.1
-    // Note: Currently the logic below does not consider shadowing and might have multiple results
-    // with the same type name
-    result.(TopLevelType).getCompilationUnit() = this
-    or
-    exists(ImportStaticTypeMember importDecl |
-      importDecl.getCompilationUnit() = this and
-      result = importDecl.getATypeImport()
-    )
-    or
-    exists(ImportType importDecl |
-      importDecl.getCompilationUnit() = this and
-      result = importDecl.getImportedType()
-    )
-    or
-    exists(ImportStaticOnDemand importDecl |
-      importDecl.getCompilationUnit() = this and
-      result = importDecl.getATypeImport()
-    )
-    or
-    exists(ImportOnDemandFromType importDecl |
-      importDecl.getCompilationUnit() = this and
-      result = importDecl.getAnImport()
-    )
-    or
-    exists(ImportOnDemandFromPackage importDecl |
-      importDecl.getCompilationUnit() = this and
-      result = importDecl.getAnImport()
-    )
-    or
-    // From same package or java.lang, see https://docs.oracle.com/javase/specs/jls/se17/html/jls-7.html
-    result.(TopLevelType).getPackage() = this.getPackage()
-    or
-    result.(TopLevelType).getPackage().hasName("java.lang")
-  }
-
   override string getAPrimaryQlClass() { result = "CompilationUnit" }
 }

java/ql/lib/semmle/code/java/CompilationUnit.qll

@@ -11,18 +11,22 @@
 
 import java
 
-Class getTaggedType(ThrowsTag tag) {
+RefType getTaggedType(ThrowsTag tag) {
   result.hasName(tag.getExceptionName()) and
-  result = tag.getFile().(CompilationUnit).getATypeAvailableBySimpleName()
+  exists(ImportType i | i.getFile() = tag.getFile() | i.getImportedType() = result)
 }
 
-predicate canThrow(Callable callable, Class exception) {
-  exception instanceof UncheckedThrowableType
+predicate canThrow(Callable callable, RefType exception) {
+  exists(string uncheckedException |
+    uncheckedException = "RuntimeException" or uncheckedException = "Error"
+  |
+    exception.getAnAncestor().hasQualifiedName("java.lang", uncheckedException)
+  )
   or
   callable.getAnException().getType().getADescendant() = exception
 }
 
-from ThrowsTag throwsTag, Class thrownType, Callable docMethod
+from ThrowsTag throwsTag, RefType thrownType, Callable docMethod
 where
   getTaggedType(throwsTag) = thrownType and
   docMethod.getDoc().getJavadoc().getAChild*() = throwsTag and