fix: solve JDT Null Analysis Mismatch Error

Author: rubenporras

org.eclipse.lsp4e/src/org/eclipse/lsp4e/operations/symbols/LSPSymbolInWorkspaceDialog.java

@@ -12,6 +12,7 @@
 package org.eclipse.lsp4e.operations.symbols;
 
 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
 import java.util.Objects;
@@ -230,10 +231,10 @@ private static List<WorkspaceSymbol> toWorkspaceSymbols(@Nullable List<? extends
 		return res;
 	}
 
-	static List<? extends WorkspaceSymbol> eitherToWorkspaceSymbols(
+	static List<@Nullable ? extends WorkspaceSymbol> eitherToWorkspaceSymbols(
 			final @Nullable Either<List<? extends SymbolInformation>, List<@Nullable ? extends WorkspaceSymbol>> source) {
 		return source == null //
-				? List.of()
-				: source.map(LSPSymbolInWorkspaceDialog::toWorkspaceSymbols, Function.identity());
+						? Collections.emptyList()
+						: source.map(LSPSymbolInWorkspaceDialog::toWorkspaceSymbols, Function.identity());
 	}
 }

org.eclipse.lsp4e/src/org/eclipse/lsp4e/operations/symbols/WorkspaceSymbolsQuickAccessProvider.java

@@ -14,6 +14,7 @@
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
@@ -69,7 +70,7 @@ public QuickAccessElement[] computeElements(String query, IProgressMonitor monit
 			CompletableFuture.allOf(usedLanguageServerWrappers.stream()
 					.map(w -> w.execute(ls -> ls.getWorkspaceService().symbol(params).thenAcceptAsync((@Nullable Either<List<? extends SymbolInformation>, List<@Nullable ? extends WorkspaceSymbol>> symbols) -> {
 						if (symbols != null) {
-							res.addAll(LSPSymbolInWorkspaceDialog.eitherToWorkspaceSymbols(symbols).stream().map(WorkspaceSymbolQuickAccessElement::new)
+							res.addAll(LSPSymbolInWorkspaceDialog.eitherToWorkspaceSymbols(symbols).stream().filter(Objects::nonNull).map(WorkspaceSymbolQuickAccessElement::new)
 									.toList());
 						}
 					}))).toArray(CompletableFuture[]::new)).get(1, TimeUnit.SECONDS);