Stream Nullity

lib/src/main/java/net/sridharan/sample/Scratch.java

@@ -0,0 +1,39 @@
+// Copyright 2024 Canva Inc. All Rights Reserved.
+
+package net.sridharan.sample;
+
+import org.jspecify.annotations.NonNull;
+import org.jspecify.annotations.Nullable;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.stream.Collectors;
+
+class Scratch {
+  public record Foo(@Nullable String bar, String baz){}
+  record Qux(String a, String b){}
+  record Transformer(){
+    public static Qux transform(String bar) {
+      var split = bar.split("-");
+      return new Qux(split[0], split[1]);
+    }
+  }
+
+  // Not fine here, but fine in my environment
+  void streams() {
+    List<Foo> foos = List.of(new Foo("a-b", "c"));
+    foos.stream()
+            .filter(f -> f.bar != null)
+            // NullAway complains about nullability of bar even though bar is null checked
+            .collect(Collectors.toMap(f -> Transformer.transform(f.bar), f -> f.baz));
+  }
+
+  // Fine in this environment but not in mine
+  // In my env, Nullaway complains about the nullability of bar in collect as above
+  void streams2() {
+    List<Foo> foos = List.of(new Foo("a-b", "c"));
+    foos.stream()
+            .filter(f -> f.bar != null)
+            .collect(Collectors.toMap(f -> f.bar, f -> f.baz));
+  }
+}