[singular][issue #2221] the plural builder method now nullchecks its argument with configurable results.

32 files changed, 315 insertions, 35 deletions

diff --git a/test/transform/resource/after-ecj/BuilderDefaultsWarnings.java b/test/transform/resource/after-ecj/BuilderDefaultsWarnings.java
index cc995aa2..e9ecad90 100644
--- a/test/transform/resource/after-ecj/BuilderDefaultsWarnings.java
+++ b/test/transform/resource/after-ecj/BuilderDefaultsWarnings.java
@@ -23,6 +23,8 @@ public @Builder class BuilderDefaultsWarnings {
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderDefaultsWarnings.BuilderDefaultsWarningsBuilder items(final java.util.Collection<? extends String> items) {
+      if ((items == null))
+          throw new java.lang.NullPointerException("items cannot be null");
       if ((this.items == null))
           this.items = new java.util.ArrayList<String>();
       this.items.addAll(items);
diff --git a/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypes.java b/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypes.java
index 18c01c2e..a371de1c 100644
--- a/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypes.java
+++ b/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypes.java
@@ -25,6 +25,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularAnnotatedTypes.BuilderSingularAnnotatedTypesBuilder foos(final java.util.Collection<? extends @MyAnnotation @NonNull String> foos) {
+      if ((foos == null))
+          throw new java.lang.NullPointerException("foos cannot be null");
       if ((this.foos == null))
           this.foos = new java.util.ArrayList<@MyAnnotation @NonNull String>();
       this.foos.addAll(foos);
@@ -54,6 +56,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularAnnotatedTypes.BuilderSingularAnnotatedTypesBuilder bars(final java.util.Map<? extends @MyAnnotation @NonNull String, ? extends @MyAnnotation @NonNull Integer> bars) {
+      if ((bars == null))
+          throw new java.lang.NullPointerException("bars cannot be null");
       if ((this.bars$key == null))
           {
             this.bars$key = new java.util.ArrayList<@MyAnnotation @NonNull String>();
diff --git a/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypesWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypesWithSetterPrefix.java
index 20197f83..cbb73c2f 100644
--- a/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypesWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularAnnotatedTypesWithSetterPrefix.java
@@ -25,6 +25,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularAnnotatedTypesWithSetterPrefix.BuilderSingularAnnotatedTypesWithSetterPrefixBuilder withFoos(final java.util.Collection<? extends @MyAnnotation @NonNull String> foos) {
+      if ((foos == null))
+          throw new java.lang.NullPointerException("foos cannot be null");
       if ((this.foos == null))
           this.foos = new java.util.ArrayList<@MyAnnotation @NonNull String>();
       this.foos.addAll(foos);
@@ -54,6 +56,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularAnnotatedTypesWithSetterPrefix.BuilderSingularAnnotatedTypesWithSetterPrefixBuilder withBars(final java.util.Map<? extends @MyAnnotation @NonNull String, ? extends @MyAnnotation @NonNull Integer> bars) {
+      if ((bars == null))
+          throw new java.lang.NullPointerException("bars cannot be null");
       if ((this.bars$key == null))
           {
             this.bars$key = new java.util.ArrayList<@MyAnnotation @NonNull String>();
diff --git a/test/transform/resource/after-ecj/BuilderSingularGuavaListsSets.java b/test/transform/resource/after-ecj/BuilderSingularGuavaListsSets.java
index 88a3096f..d0c68234 100644
--- a/test/transform/resource/after-ecj/BuilderSingularGuavaListsSets.java
+++ b/test/transform/resource/after-ecj/BuilderSingularGuavaListsSets.java
@@ -21,6 +21,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaListsSets.BuilderSingularGuavaListsSetsBuilder<T> cards(final java.lang.Iterable<? extends T> cards) {
+      if ((cards == null))
+          throw new java.lang.NullPointerException("cards cannot be null");
       if ((this.cards == null))
           this.cards = com.google.common.collect.ImmutableList.builder();
       this.cards.addAll(cards);
@@ -37,6 +39,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaListsSets.BuilderSingularGuavaListsSetsBuilder<T> frogs(final java.lang.Iterable<? extends Number> frogs) {
+      if ((frogs == null))
+          throw new java.lang.NullPointerException("frogs cannot be null");
       if ((this.frogs == null))
           this.frogs = com.google.common.collect.ImmutableList.builder();
       this.frogs.addAll(frogs);
@@ -53,6 +57,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaListsSets.BuilderSingularGuavaListsSetsBuilder<T> rawSet(final java.lang.Iterable<?> rawSet) {
+      if ((rawSet == null))
+          throw new java.lang.NullPointerException("rawSet cannot be null");
       if ((this.rawSet == null))
           this.rawSet = com.google.common.collect.ImmutableSet.builder();
       this.rawSet.addAll(rawSet);
@@ -69,6 +75,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaListsSets.BuilderSingularGuavaListsSetsBuilder<T> passes(final java.lang.Iterable<? extends String> passes) {
+      if ((passes == null))
+          throw new java.lang.NullPointerException("passes cannot be null");
       if ((this.passes == null))
           this.passes = com.google.common.collect.ImmutableSortedSet.naturalOrder();
       this.passes.addAll(passes);
@@ -85,6 +93,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaListsSets.BuilderSingularGuavaListsSetsBuilder<T> users(final com.google.common.collect.Table<? extends Number, ? extends Number, ? extends String> users) {
+      if ((users == null))
+          throw new java.lang.NullPointerException("users cannot be null");
       if ((this.users == null))
           this.users = com.google.common.collect.ImmutableTable.builder();
       this.users.putAll(users);
diff --git a/test/transform/resource/after-ecj/BuilderSingularGuavaMaps.java b/test/transform/resource/after-ecj/BuilderSingularGuavaMaps.java
index 618ee8db..08c72f98 100644
--- a/test/transform/resource/after-ecj/BuilderSingularGuavaMaps.java
+++ b/test/transform/resource/after-ecj/BuilderSingularGuavaMaps.java
@@ -17,6 +17,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaMaps.BuilderSingularGuavaMapsBuilder<K, V> battleaxes(final java.util.Map<? extends K, ? extends V> battleaxes) {
+      if ((battleaxes == null))
+          throw new java.lang.NullPointerException("battleaxes cannot be null");
       if ((this.battleaxes == null))
           this.battleaxes = com.google.common.collect.ImmutableMap.builder();
       this.battleaxes.putAll(battleaxes);
@@ -33,6 +35,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaMaps.BuilderSingularGuavaMapsBuilder<K, V> vertices(final java.util.Map<? extends Integer, ? extends V> vertices) {
+      if ((vertices == null))
+          throw new java.lang.NullPointerException("vertices cannot be null");
       if ((this.vertices == null))
           this.vertices = com.google.common.collect.ImmutableSortedMap.naturalOrder();
       this.vertices.putAll(vertices);
@@ -49,6 +53,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularGuavaMaps.BuilderSingularGuavaMapsBuilder<K, V> rawMap(final java.util.Map<?, ?> rawMap) {
+      if ((rawMap == null))
+          throw new java.lang.NullPointerException("rawMap cannot be null");
       if ((this.rawMap == null))
           this.rawMap = com.google.common.collect.ImmutableBiMap.builder();
       this.rawMap.putAll(rawMap);
diff --git a/test/transform/resource/after-ecj/BuilderSingularLists.java b/test/transform/resource/after-ecj/BuilderSingularLists.java
index 66247c3f..c201a32b 100644
--- a/test/transform/resource/after-ecj/BuilderSingularLists.java
+++ b/test/transform/resource/after-ecj/BuilderSingularLists.java
@@ -17,6 +17,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularLists.BuilderSingularListsBuilder<T> children(final java.util.Collection<? extends T> children) {
+      if ((children == null))
+          throw new java.lang.NullPointerException("children cannot be null");
       if ((this.children == null))
           this.children = new java.util.ArrayList<T>();
       this.children.addAll(children);
@@ -34,6 +36,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularLists.BuilderSingularListsBuilder<T> scarves(final java.util.Collection<? extends Number> scarves) {
+      if ((scarves == null))
+          throw new java.lang.NullPointerException("scarves cannot be null");
       if ((this.scarves == null))
           this.scarves = new java.util.ArrayList<Number>();
       this.scarves.addAll(scarves);
@@ -51,6 +55,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularLists.BuilderSingularListsBuilder<T> rawList(final java.util.Collection<?> rawList) {
+      if ((rawList == null))
+          throw new java.lang.NullPointerException("rawList cannot be null");
       if ((this.rawList == null))
           this.rawList = new java.util.ArrayList<java.lang.Object>();
       this.rawList.addAll(rawList);
diff --git a/test/transform/resource/after-ecj/BuilderSingularMaps.java b/test/transform/resource/after-ecj/BuilderSingularMaps.java
index 977ee527..d53e7022 100644
--- a/test/transform/resource/after-ecj/BuilderSingularMaps.java
+++ b/test/transform/resource/after-ecj/BuilderSingularMaps.java
@@ -25,6 +25,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMaps.BuilderSingularMapsBuilder<K, V> women(final java.util.Map<? extends K, ? extends V> women) {
+      if ((women == null))
+          throw new java.lang.NullPointerException("women cannot be null");
       if ((this.women$key == null))
           {
             this.women$key = new java.util.ArrayList<K>();
@@ -56,6 +58,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMaps.BuilderSingularMapsBuilder<K, V> men(final java.util.Map<? extends K, ? extends Number> men) {
+      if ((men == null))
+          throw new java.lang.NullPointerException("men cannot be null");
       if ((this.men$key == null))
           {
             this.men$key = new java.util.ArrayList<K>();
@@ -87,6 +91,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMaps.BuilderSingularMapsBuilder<K, V> rawMap(final java.util.Map<?, ?> rawMap) {
+      if ((rawMap == null))
+          throw new java.lang.NullPointerException("rawMap cannot be null");
       if ((this.rawMap$key == null))
           {
             this.rawMap$key = new java.util.ArrayList<java.lang.Object>();
@@ -118,6 +124,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMaps.BuilderSingularMapsBuilder<K, V> stringMap(final java.util.Map<? extends String, ? extends V> stringMap) {
+      if ((stringMap == null))
+          throw new java.lang.NullPointerException("stringMap cannot be null");
       if ((this.stringMap$key == null))
           {
             this.stringMap$key = new java.util.ArrayList<String>();
diff --git a/test/transform/resource/after-ecj/BuilderSingularMapsWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularMapsWithSetterPrefix.java
index 0832fdc0..0bddd22c 100644
--- a/test/transform/resource/after-ecj/BuilderSingularMapsWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularMapsWithSetterPrefix.java
@@ -25,16 +25,19 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> withWomen(final java.util.Map<? extends K, ? extends V> women) {
-      if ((this.women$key == null))
+      if ((women != null))
           {
-            this.women$key = new java.util.ArrayList<K>();
-            this.women$value = new java.util.ArrayList<V>();
+            if ((this.women$key == null))
+                {
+                  this.women$key = new java.util.ArrayList<K>();
+                  this.women$value = new java.util.ArrayList<V>();
+                }
+            for (java.util.Map.Entry<? extends K, ? extends V> $lombokEntry : women.entrySet()) 
+              {
+                this.women$key.add($lombokEntry.getKey());
+                this.women$value.add($lombokEntry.getValue());
+              }
           }
-      for (java.util.Map.Entry<? extends K, ? extends V> $lombokEntry : women.entrySet()) 
-        {
-          this.women$key.add($lombokEntry.getKey());
-          this.women$value.add($lombokEntry.getValue());
-        }
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> clearWomen() {
@@ -56,16 +59,19 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> withMen(final java.util.Map<? extends K, ? extends Number> men) {
-      if ((this.men$key == null))
+      if ((men != null))
           {
-            this.men$key = new java.util.ArrayList<K>();
-            this.men$value = new java.util.ArrayList<Number>();
+            if ((this.men$key == null))
+                {
+                  this.men$key = new java.util.ArrayList<K>();
+                  this.men$value = new java.util.ArrayList<Number>();
+                }
+            for (java.util.Map.Entry<? extends K, ? extends Number> $lombokEntry : men.entrySet()) 
+              {
+                this.men$key.add($lombokEntry.getKey());
+                this.men$value.add($lombokEntry.getValue());
+              }
           }
-      for (java.util.Map.Entry<? extends K, ? extends Number> $lombokEntry : men.entrySet()) 
-        {
-          this.men$key.add($lombokEntry.getKey());
-          this.men$value.add($lombokEntry.getValue());
-        }
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> clearMen() {
@@ -87,16 +93,19 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> withRawMap(final java.util.Map<?, ?> rawMap) {
-      if ((this.rawMap$key == null))
+      if ((rawMap != null))
           {
-            this.rawMap$key = new java.util.ArrayList<java.lang.Object>();
-            this.rawMap$value = new java.util.ArrayList<java.lang.Object>();
+            if ((this.rawMap$key == null))
+                {
+                  this.rawMap$key = new java.util.ArrayList<java.lang.Object>();
+                  this.rawMap$value = new java.util.ArrayList<java.lang.Object>();
+                }
+            for (java.util.Map.Entry<?, ?> $lombokEntry : rawMap.entrySet()) 
+              {
+                this.rawMap$key.add($lombokEntry.getKey());
+                this.rawMap$value.add($lombokEntry.getValue());
+              }
           }
-      for (java.util.Map.Entry<?, ?> $lombokEntry : rawMap.entrySet()) 
-        {
-          this.rawMap$key.add($lombokEntry.getKey());
-          this.rawMap$value.add($lombokEntry.getValue());
-        }
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> clearRawMap() {
@@ -118,16 +127,19 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> withStringMap(final java.util.Map<? extends String, ? extends V> stringMap) {
-      if ((this.stringMap$key == null))
+      if ((stringMap != null))
           {
-            this.stringMap$key = new java.util.ArrayList<String>();
-            this.stringMap$value = new java.util.ArrayList<V>();
+            if ((this.stringMap$key == null))
+                {
+                  this.stringMap$key = new java.util.ArrayList<String>();
+                  this.stringMap$value = new java.util.ArrayList<V>();
+                }
+            for (java.util.Map.Entry<? extends String, ? extends V> $lombokEntry : stringMap.entrySet()) 
+              {
+                this.stringMap$key.add($lombokEntry.getKey());
+                this.stringMap$value.add($lombokEntry.getValue());
+              }
           }
-      for (java.util.Map.Entry<? extends String, ? extends V> $lombokEntry : stringMap.entrySet()) 
-        {
-          this.stringMap$key.add($lombokEntry.getKey());
-          this.stringMap$value.add($lombokEntry.getValue());
-        }
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> clearStringMap() {
@@ -206,4 +218,4 @@ import lombok.Singular;
   public static @java.lang.SuppressWarnings("all") <K, V>BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V> builder() {
     return new BuilderSingularMapsWithSetterPrefix.BuilderSingularMapsWithSetterPrefixBuilder<K, V>();
   }
-}
+}
\ No newline at end of file
diff --git a/test/transform/resource/after-ecj/BuilderSingularNoAuto.java b/test/transform/resource/after-ecj/BuilderSingularNoAuto.java
index c1ac51eb..47b413b3 100644
--- a/test/transform/resource/after-ecj/BuilderSingularNoAuto.java
+++ b/test/transform/resource/after-ecj/BuilderSingularNoAuto.java
@@ -15,6 +15,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAuto.BuilderSingularNoAutoBuilder things(final java.util.Collection<? extends String> things) {
+      if ((things == null))
+          throw new java.lang.NullPointerException("things cannot be null");
       if ((this.things == null))
           this.things = new java.util.ArrayList<String>();
       this.things.addAll(things);
@@ -32,6 +34,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAuto.BuilderSingularNoAutoBuilder widgets(final java.util.Collection<? extends String> widgets) {
+      if ((widgets == null))
+          throw new java.lang.NullPointerException("widgets cannot be null");
       if ((this.widgets == null))
           this.widgets = new java.util.ArrayList<String>();
       this.widgets.addAll(widgets);
@@ -49,6 +53,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAuto.BuilderSingularNoAutoBuilder items(final java.util.Collection<? extends String> items) {
+      if ((items == null))
+          throw new java.lang.NullPointerException("items cannot be null");
       if ((this.items == null))
           this.items = new java.util.ArrayList<String>();
       this.items.addAll(items);
diff --git a/test/transform/resource/after-ecj/BuilderSingularNoAutoWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularNoAutoWithSetterPrefix.java
index e869e871..85cfda71 100644
--- a/test/transform/resource/after-ecj/BuilderSingularNoAutoWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularNoAutoWithSetterPrefix.java
@@ -15,6 +15,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAutoWithSetterPrefix.BuilderSingularNoAutoWithSetterPrefixBuilder withThings(final java.util.Collection<? extends String> things) {
+      if ((things == null))
+          throw new java.lang.NullPointerException("things cannot be null");
       if ((this.things == null))
           this.things = new java.util.ArrayList<String>();
       this.things.addAll(things);
@@ -32,6 +34,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAutoWithSetterPrefix.BuilderSingularNoAutoWithSetterPrefixBuilder withWidgets(final java.util.Collection<? extends String> widgets) {
+      if ((widgets == null))
+          throw new java.lang.NullPointerException("widgets cannot be null");
       if ((this.widgets == null))
           this.widgets = new java.util.ArrayList<String>();
       this.widgets.addAll(widgets);
@@ -49,6 +53,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularNoAutoWithSetterPrefix.BuilderSingularNoAutoWithSetterPrefixBuilder withItems(final java.util.Collection<? extends String> items) {
+      if ((items == null))
+          throw new java.lang.NullPointerException("items cannot be null");
       if ((this.items == null))
           this.items = new java.util.ArrayList<String>();
       this.items.addAll(items);
diff --git a/test/transform/resource/after-ecj/BuilderSingularNullBehavior1.java b/test/transform/resource/after-ecj/BuilderSingularNullBehavior1.java
new file mode 100644
index 00000000..7ef52eb8
--- /dev/null
+++ b/test/transform/resource/after-ecj/BuilderSingularNullBehavior1.java
@@ -0,0 +1,154 @@
+import java.util.List;
+import java.util.Collection;
+import lombok.Singular;
+import lombok.Singular.NullCollectionBehavior;
+@lombok.Builder class BuilderSingularNullBehavior1 {
+  public static @java.lang.SuppressWarnings("all") class BuilderSingularNullBehavior1Builder {
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<String> names;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<String> locations;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<String> whatevers;
+    private @java.lang.SuppressWarnings("all") java.util.ArrayList<String> doohickeys;
+    @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1Builder() {
+      super();
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder name(final String name) {
+      if ((this.names == null))
+          this.names = new java.util.ArrayList<String>();
+      this.names.add(name);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder names(final java.util.Collection<? extends String> names) {
+      if ((names == null))
+          throw new java.lang.NullPointerException("names cannot be null");
+      if ((this.names == null))
+          this.names = new java.util.ArrayList<String>();
+      this.names.addAll(names);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder clearNames() {
+      if ((this.names != null))
+          this.names.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder location(final String location) {
+      if ((this.locations == null))
+          this.locations = new java.util.ArrayList<String>();
+      this.locations.add(location);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder locations(final java.util.Collection<? extends String> locations) {
+      java.util.Objects.requireNonNull(locations, "locations cannot be null");
+      if ((this.locations == null))
+          this.locations = new java.util.ArrayList<String>();
+      this.locations.addAll(locations);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder clearLocations() {
+      if ((this.locations != null))
+          this.locations.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder whatever(final String whatever) {
+      if ((this.whatevers == null))
+          this.whatevers = new java.util.ArrayList<String>();
+      this.whatevers.add(whatever);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder whatevers(final java.util.Collection<? extends String> whatevers) {
+      com.google.common.base.Preconditions.checkNotNull(whatevers, "whatevers cannot be null");
+      if ((this.whatevers == null))
+          this.whatevers = new java.util.ArrayList<String>();
+      this.whatevers.addAll(whatevers);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder clearWhatevers() {
+      if ((this.whatevers != null))
+          this.whatevers.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder doohickey(final String doohickey) {
+      if ((this.doohickeys == null))
+          this.doohickeys = new java.util.ArrayList<String>();
+      this.doohickeys.add(doohickey);
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder doohickeys(final java.util.Collection<? extends String> doohickeys) {
+      if ((doohickeys != null))
+          {
+            if ((this.doohickeys == null))
+                this.doohickeys = new java.util.ArrayList<String>();
+            this.doohickeys.addAll(doohickeys);
+          }
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder clearDoohickeys() {
+      if ((this.doohickeys != null))
+          this.doohickeys.clear();
+      return this;
+    }
+    public @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1 build() {
+      java.util.List<String> names;
+      switch (((this.names == null) ? 0 : this.names.size())) {
+      case 0 :
+          names = java.util.Collections.emptyList();
+          break;
+      case 1 :
+          names = java.util.Collections.singletonList(this.names.get(0));
+          break;
+      default :
+          names = java.util.Collections.unmodifiableList(new java.util.ArrayList<String>(this.names));
+      }
+      java.util.List<String> locations;
+      switch (((this.locations == null) ? 0 : this.locations.size())) {
+      case 0 :
+          locations = java.util.Collections.emptyList();
+          break;
+      case 1 :
+          locations = java.util.Collections.singletonList(this.locations.get(0));
+          break;
+      default :
+          locations = java.util.Collections.unmodifiableList(new java.util.ArrayList<String>(this.locations));
+      }
+      java.util.List<String> whatevers;
+      switch (((this.whatevers == null) ? 0 : this.whatevers.size())) {
+      case 0 :
+          whatevers = java.util.Collections.emptyList();
+          break;
+      case 1 :
+          whatevers = java.util.Collections.singletonList(this.whatevers.get(0));
+          break;
+      default :
+          whatevers = java.util.Collections.unmodifiableList(new java.util.ArrayList<String>(this.whatevers));
+      }
+      java.util.List<String> doohickeys;
+      switch (((this.doohickeys == null) ? 0 : this.doohickeys.size())) {
+      case 0 :
+          doohickeys = java.util.Collections.emptyList();
+          break;
+      case 1 :
+          doohickeys = java.util.Collections.singletonList(this.doohickeys.get(0));
+          break;
+      default :
+          doohickeys = java.util.Collections.unmodifiableList(new java.util.ArrayList<String>(this.doohickeys));
+      }
+      return new BuilderSingularNullBehavior1(names, locations, whatevers, doohickeys);
+    }
+    public @java.lang.Override @java.lang.SuppressWarnings("all") java.lang.String toString() {
+      return (((((((("BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder(names=" + this.names) + ", locations=") + this.locations) + ", whatevers=") + this.whatevers) + ", doohickeys=") + this.doohickeys) + ")");
+    }
+  }
+  private @Singular List<String> names;
+  private @Singular(nullBehavior = Singular.NullCollectionBehavior.JDK) List<String> locations;
+  private @Singular(nullBehavior = NullCollectionBehavior.GUAVA) List<String> whatevers;
+  private @Singular(nullBehavior = lombok.Singular.NullCollectionBehavior.IGNORE) List<String> doohickeys;
+  @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1(final List<String> names, final List<String> locations, final List<String> whatevers, final List<String> doohickeys) {
+    super();
+    this.names = names;
+    this.locations = locations;
+    this.whatevers = whatevers;
+    this.doohickeys = doohickeys;
+  }
+  public static @java.lang.SuppressWarnings("all") BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder builder() {
+    return new BuilderSingularNullBehavior1.BuilderSingularNullBehavior1Builder();
+  }
+}
\ No newline at end of file
diff --git a/test/transform/resource/after-ecj/BuilderSingularRedirectToGuava.java b/test/transform/resource/after-ecj/BuilderSingularRedirectToGuava.java
index 9e7028d6..867bf7fa 100644
--- a/test/transform/resource/after-ecj/BuilderSingularRedirectToGuava.java
+++ b/test/transform/resource/after-ecj/BuilderSingularRedirectToGuava.java
@@ -17,6 +17,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularRedirectToGuava.BuilderSingularRedirectToGuavaBuilder dangerMice(final java.lang.Iterable<? extends String> dangerMice) {
+      if ((dangerMice == null))
+          throw new java.lang.NullPointerException("dangerMice cannot be null");
       if ((this.dangerMice == null))
           this.dangerMice = com.google.common.collect.ImmutableSet.builder();
       this.dangerMice.addAll(dangerMice);
@@ -33,6 +35,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularRedirectToGuava.BuilderSingularRedirectToGuavaBuilder things(final java.util.Map<? extends Integer, ? extends Number> things) {
+      if ((things == null))
+          throw new java.lang.NullPointerException("things cannot be null");
       if ((this.things == null))
           this.things = com.google.common.collect.ImmutableSortedMap.naturalOrder();
       this.things.putAll(things);
@@ -49,6 +53,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularRedirectToGuava.BuilderSingularRedirectToGuavaBuilder doohickeys(final java.lang.Iterable<? extends Class<?>> doohickeys) {
+      if ((doohickeys == null))
+          throw new java.lang.NullPointerException("doohickeys cannot be null");
       if ((this.doohickeys == null))
           this.doohickeys = com.google.common.collect.ImmutableList.builder();
       this.doohickeys.addAll(doohickeys);
diff --git a/test/transform/resource/after-ecj/BuilderSingularSets.java b/test/transform/resource/after-ecj/BuilderSingularSets.java
index b6ef04cb..6cfa5203 100644
--- a/test/transform/resource/after-ecj/BuilderSingularSets.java
+++ b/test/transform/resource/after-ecj/BuilderSingularSets.java
@@ -17,6 +17,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSets.BuilderSingularSetsBuilder<T> dangerMice(final java.util.Collection<? extends T> dangerMice) {
+      if ((dangerMice == null))
+          throw new java.lang.NullPointerException("dangerMice cannot be null");
       if ((this.dangerMice == null))
           this.dangerMice = new java.util.ArrayList<T>();
       this.dangerMice.addAll(dangerMice);
@@ -34,6 +36,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSets.BuilderSingularSetsBuilder<T> octopodes(final java.util.Collection<? extends Number> octopodes) {
+      if ((octopodes == null))
+          throw new java.lang.NullPointerException("octopodes cannot be null");
       if ((this.octopodes == null))
           this.octopodes = new java.util.ArrayList<Number>();
       this.octopodes.addAll(octopodes);
@@ -51,6 +55,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSets.BuilderSingularSetsBuilder<T> rawSet(final java.util.Collection<?> rawSet) {
+      if ((rawSet == null))
+          throw new java.lang.NullPointerException("rawSet cannot be null");
       if ((this.rawSet == null))
           this.rawSet = new java.util.ArrayList<java.lang.Object>();
       this.rawSet.addAll(rawSet);
@@ -68,6 +74,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSets.BuilderSingularSetsBuilder<T> stringSet(final java.util.Collection<? extends String> stringSet) {
+      if ((stringSet == null))
+          throw new java.lang.NullPointerException("stringSet cannot be null");
       if ((this.stringSet == null))
           this.stringSet = new java.util.ArrayList<String>();
       this.stringSet.addAll(stringSet);
diff --git a/test/transform/resource/after-ecj/BuilderSingularSetsWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularSetsWithSetterPrefix.java
index b857b586..cdc0390c 100644
--- a/test/transform/resource/after-ecj/BuilderSingularSetsWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularSetsWithSetterPrefix.java
@@ -17,6 +17,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSetsWithSetterPrefix.BuilderSingularSetsWithSetterPrefixBuilder<T> withDangerMice(final java.util.Collection<? extends T> dangerMice) {
+      if ((dangerMice == null))
+          throw new java.lang.NullPointerException("dangerMice cannot be null");
       if ((this.dangerMice == null))
           this.dangerMice = new java.util.ArrayList<T>();
       this.dangerMice.addAll(dangerMice);
@@ -34,6 +36,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSetsWithSetterPrefix.BuilderSingularSetsWithSetterPrefixBuilder<T> withOctopodes(final java.util.Collection<? extends Number> octopodes) {
+      if ((octopodes == null))
+          throw new java.lang.NullPointerException("octopodes cannot be null");
       if ((this.octopodes == null))
           this.octopodes = new java.util.ArrayList<Number>();
       this.octopodes.addAll(octopodes);
@@ -51,6 +55,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSetsWithSetterPrefix.BuilderSingularSetsWithSetterPrefixBuilder<T> withRawSet(final java.util.Collection<?> rawSet) {
+      if ((rawSet == null))
+          throw new java.lang.NullPointerException("rawSet cannot be null");
       if ((this.rawSet == null))
           this.rawSet = new java.util.ArrayList<java.lang.Object>();
       this.rawSet.addAll(rawSet);
@@ -68,6 +74,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularSetsWithSetterPrefix.BuilderSingularSetsWithSetterPrefixBuilder<T> withStringSet(final java.util.Collection<? extends String> stringSet) {
+      if ((stringSet == null))
+          throw new java.lang.NullPointerException("stringSet cannot be null");
       if ((this.stringSet == null))
           this.stringSet = new java.util.ArrayList<String>();
       this.stringSet.addAll(stringSet);
diff --git a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
index 99a277e3..c01b5b8f 100644
--- a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
+++ b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNull.java
@@ -12,6 +12,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularToBuilderWithNull.BuilderSingularToBuilderWithNullBuilder elems(final java.util.Collection<? extends String> elems) {
+      if ((elems == null))
+          throw new java.lang.NullPointerException("elems cannot be null");
       if ((this.elems == null))
           this.elems = new java.util.ArrayList<String>();
       this.elems.addAll(elems);
diff --git a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNullWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNullWithSetterPrefix.java
index a0223598..092f0b55 100644
--- a/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNullWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularToBuilderWithNullWithSetterPrefix.java
@@ -12,6 +12,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularToBuilderWithNullWithSetterPrefix.BuilderSingularToBuilderWithNullWithSetterPrefixBuilder withElems(final java.util.Collection<? extends String> elems) {
+      if ((elems == null))
+          throw new java.lang.NullPointerException("elems cannot be null");
       if ((this.elems == null))
           this.elems = new java.util.ArrayList<String>();
       this.elems.addAll(elems);
diff --git a/test/transform/resource/after-ecj/BuilderSingularWildcardListsWithToBuilder.java b/test/transform/resource/after-ecj/BuilderSingularWildcardListsWithToBuilder.java
index e9c61eb6..8a00644d 100644
--- a/test/transform/resource/after-ecj/BuilderSingularWildcardListsWithToBuilder.java
+++ b/test/transform/resource/after-ecj/BuilderSingularWildcardListsWithToBuilder.java
@@ -15,6 +15,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularWildcardListsWithToBuilder.BuilderSingularWildcardListsWithToBuilderBuilder objects(final java.util.Collection<?> objects) {
+      if ((objects == null))
+          throw new java.lang.NullPointerException("objects cannot be null");
       if ((this.objects == null))
           this.objects = new java.util.ArrayList<java.lang.Object>();
       this.objects.addAll(objects);
@@ -32,6 +34,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularWildcardListsWithToBuilder.BuilderSingularWildcardListsWithToBuilderBuilder numbers(final java.util.Collection<? extends Number> numbers) {
+      if ((numbers == null))
+          throw new java.lang.NullPointerException("numbers cannot be null");
       if ((this.numbers == null))
           this.numbers = new java.util.ArrayList<Number>();
       this.numbers.addAll(numbers);
diff --git a/test/transform/resource/after-ecj/BuilderSingularWithPrefixes.java b/test/transform/resource/after-ecj/BuilderSingularWithPrefixes.java
index 5f8a8ee0..b4fa5cbe 100644
--- a/test/transform/resource/after-ecj/BuilderSingularWithPrefixes.java
+++ b/test/transform/resource/after-ecj/BuilderSingularWithPrefixes.java
@@ -12,6 +12,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularWithPrefixes.BuilderSingularWithPrefixesBuilder elems(final java.util.Collection<? extends String> elems) {
+      if ((elems == null))
+          throw new java.lang.NullPointerException("elems cannot be null");
       if ((this.elems == null))
           this.elems = new java.util.ArrayList<String>();
       this.elems.addAll(elems);
diff --git a/test/transform/resource/after-ecj/BuilderSingularWithPrefixesWithSetterPrefix.java b/test/transform/resource/after-ecj/BuilderSingularWithPrefixesWithSetterPrefix.java
index 377a9c27..f10482d5 100644
--- a/test/transform/resource/after-ecj/BuilderSingularWithPrefixesWithSetterPrefix.java
+++ b/test/transform/resource/after-ecj/BuilderSingularWithPrefixesWithSetterPrefix.java
@@ -12,6 +12,8 @@ import lombok.Singular;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderSingularWithPrefixesWithSetterPrefix.BuilderSingularWithPrefixesWithSetterPrefixBuilder withElems(final java.util.Collection<? extends String> elems) {
+      if ((elems == null))
+          throw new java.lang.NullPointerException("elems cannot be null");
       if ((this.elems == null))
           this.elems = new java.util.ArrayList<String>();
       this.elems.addAll(elems);
diff --git a/test/transform/resource/after-ecj/BuilderWithDeprecated.java b/test/transform/resource/after-ecj/BuilderWithDeprecated.java
index 24d35df1..9dcddc49 100644
--- a/test/transform/resource/after-ecj/BuilderWithDeprecated.java
+++ b/test/transform/resource/after-ecj/BuilderWithDeprecated.java
@@ -25,6 +25,8 @@ public @Builder class BuilderWithDeprecated {
       return this;
     }
     public @java.lang.Deprecated @java.lang.SuppressWarnings("all") BuilderWithDeprecated.BuilderWithDeprecatedBuilder strings(final java.util.Collection<? extends String> strings) {
+      if ((strings == null))
+          throw new java.lang.NullPointerException("strings cannot be null");
       if ((this.strings == null))
           this.strings = new java.util.ArrayList<String>();
       this.strings.addAll(strings);
@@ -42,6 +44,8 @@ public @Builder class BuilderWithDeprecated {
       return this;
     }
     public @java.lang.Deprecated @java.lang.SuppressWarnings("all") BuilderWithDeprecated.BuilderWithDeprecatedBuilder numbers(final java.lang.Iterable<? extends Integer> numbers) {
+      if ((numbers == null))
+          throw new java.lang.NullPointerException("numbers cannot be null");
       if ((this.numbers == null))
           this.numbers = com.google.common.collect.ImmutableList.builder();
       this.numbers.addAll(numbers);
diff --git a/test/transform/resource/after-ecj/BuilderWithToBuilder.java b/test/transform/resource/after-ecj/BuilderWithToBuilder.java
index 6d935736..ec72bdb8 100644
--- a/test/transform/resource/after-ecj/BuilderWithToBuilder.java
+++ b/test/transform/resource/after-ecj/BuilderWithToBuilder.java
@@ -28,6 +28,8 @@ import lombok.Builder;
       return this;
     }
     public @java.lang.SuppressWarnings("all") BuilderWithToBuilder.BuilderWithToBuilderBuilder<T> bars(final java.util.Collection<? extends T> bars) {
+      if ((bars == null))
+          throw new java.lang.NullPointerException("bars cannot be null");
       if ((this.bars == null))
           this.bars = new java.util.ArrayList<T>();
       this.bars.addAll(bars);
diff --git a/test/transform/resource/after-ecj/CheckerFrameworkBuilder.java b/test/transform/resource/after-ecj/CheckerFrameworkBuilder.java
index d2163ef5..d9201e39 100644
--- a/test/transform/resource/after-ecj/CheckerFrameworkBuilder.java
+++ b/test/transform/resource/after-ecj/CheckerFrameworkBuilder.java
@@ -31,6 +31,8 @@ import lombok.Singular;
       return this;
     }
     public @org.checkerframework.checker.builder.qual.ReturnsReceiver @java.lang.SuppressWarnings("all") CheckerFrameworkBuilder.CheckerFrameworkBuilderBuilder names(final java.util.Collection<? extends String> names) {
+      if ((names == null))
+          throw new java.lang.NullPointerException("names cannot be null");
       if ((this.names == null))
           this.names = new java.util.ArrayList<String>();
       this.names.addAll(names);
diff --git a/test/transform/resource/after-ecj/CheckerFrameworkSuperBuilder.java b/test/transform/resource/after-ecj/CheckerFrameworkSuperBuilder.java
index 1849419e..94ec0a0c 100644
--- a/test/transform/resource/after-ecj/CheckerFrameworkSuperBuilder.java
+++ b/test/transform/resource/after-ecj/CheckerFrameworkSuperBuilder.java
@@ -32,6 +32,8 @@ class CheckerFrameworkSuperBuilder {
         return self();
       }
       public @org.checkerframework.checker.builder.qual.ReturnsReceiver @java.lang.SuppressWarnings("all") B names(final java.util.Collection<? extends String> names) {
+        if ((names == null))
+            throw new java.lang.NullPointerException("names cannot be null");
         if ((this.names == null))
             this.names = new java.util.ArrayList<String>();
         this.names.addAll(names);
diff --git a/test/transform/resource/after-ecj/I2335_BuilderMultipleObtainVia.java b/test/transform/resource/after-ecj/I2335_BuilderMultipleObtainVia.java
index 7d8b8953..9c5eb6ae 100644
--- a/test/transform/resource/after-ecj/I2335_BuilderMultipleObtainVia.java
+++ b/test/transform/resource/after-ecj/I2335_BuilderMultipleObtainVia.java
@@ -44,8 +44,8 @@ public @Builder class I2335_BuilderMultipleObtainVia {
     return new I2335_BuilderMultipleObtainVia.I2335_BuilderMultipleObtainViaBuilder();
   }
   public @java.lang.SuppressWarnings("all") I2335_BuilderMultipleObtainVia.I2335_BuilderMultipleObtainViaBuilder toBuilder() {
-    String theString = this.getTheString();
-    Long theLong = this.getTheLong();
+    final String theString = this.getTheString();
+    final Long theLong = this.getTheLong();
     return new I2335_BuilderMultipleObtainVia.I2335_BuilderMultipleObtainViaBuilder().theString(theString).theLong(theLong);
   }
 }
diff --git a/test/transform/resource/after-ecj/SuperBuilderBasic.java b/test/transform/resource/after-ecj/SuperBuilderBasic.java
index dad0ad8f..9e686f0f 100644
--- a/test/transform/resource/after-ecj/SuperBuilderBasic.java
+++ b/test/transform/resource/after-ecj/SuperBuilderBasic.java
@@ -20,6 +20,8 @@ public class SuperBuilderBasic {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items == null))

             this.items = new java.util.ArrayList<String>();

         this.items.addAll(items);

diff --git a/test/transform/resource/after-ecj/SuperBuilderBasicToBuilder.java b/test/transform/resource/after-ecj/SuperBuilderBasicToBuilder.java
index a9f111d0..e027c9d2 100644
--- a/test/transform/resource/after-ecj/SuperBuilderBasicToBuilder.java
+++ b/test/transform/resource/after-ecj/SuperBuilderBasicToBuilder.java
@@ -46,6 +46,8 @@ public class SuperBuilderBasicToBuilder {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items == null))

             this.items = new java.util.ArrayList<String>();

         this.items.addAll(items);

diff --git a/test/transform/resource/after-ecj/SuperBuilderSingularAnnotatedTypes.java b/test/transform/resource/after-ecj/SuperBuilderSingularAnnotatedTypes.java
index 809ca50c..834d2180 100644
--- a/test/transform/resource/after-ecj/SuperBuilderSingularAnnotatedTypes.java
+++ b/test/transform/resource/after-ecj/SuperBuilderSingularAnnotatedTypes.java
@@ -27,6 +27,8 @@ import lombok.Singular;
       return self();
     }
     public @java.lang.SuppressWarnings("all") B foos(final java.util.Collection<? extends @MyAnnotation @NonNull String> foos) {
+      if ((foos == null))
+          throw new java.lang.NullPointerException("foos cannot be null");
       if ((this.foos == null))
           this.foos = new java.util.ArrayList<@MyAnnotation @NonNull String>();
       this.foos.addAll(foos);
@@ -56,6 +58,8 @@ import lombok.Singular;
       return self();
     }
     public @java.lang.SuppressWarnings("all") B bars(final java.util.Map<? extends @MyAnnotation @NonNull String, ? extends @MyAnnotation @NonNull Integer> bars) {
+      if ((bars == null))
+          throw new java.lang.NullPointerException("bars cannot be null");
       if ((this.bars$key == null))
           {
             this.bars$key = new java.util.ArrayList<@MyAnnotation @NonNull String>();
diff --git a/test/transform/resource/after-ecj/SuperBuilderWithCustomBuilderMethod.java b/test/transform/resource/after-ecj/SuperBuilderWithCustomBuilderMethod.java
index 751e281b..6605ae1d 100644
--- a/test/transform/resource/after-ecj/SuperBuilderWithCustomBuilderMethod.java
+++ b/test/transform/resource/after-ecj/SuperBuilderWithCustomBuilderMethod.java
@@ -20,6 +20,8 @@ public class SuperBuilderWithCustomBuilderMethod {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items == null))

             this.items = new java.util.ArrayList<String>();

         this.items.addAll(items);

diff --git a/test/transform/resource/after-ecj/SuperBuilderWithGenerics.java b/test/transform/resource/after-ecj/SuperBuilderWithGenerics.java
index bbf07d75..89ab8821 100644
--- a/test/transform/resource/after-ecj/SuperBuilderWithGenerics.java
+++ b/test/transform/resource/after-ecj/SuperBuilderWithGenerics.java
@@ -20,6 +20,8 @@ public class SuperBuilderWithGenerics {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items == null))

             this.items = new java.util.ArrayList<String>();

         this.items.addAll(items);

diff --git a/test/transform/resource/after-ecj/SuperBuilderWithGenerics2.java b/test/transform/resource/after-ecj/SuperBuilderWithGenerics2.java
index b3ca18ec..2037f7b0 100644
--- a/test/transform/resource/after-ecj/SuperBuilderWithGenerics2.java
+++ b/test/transform/resource/after-ecj/SuperBuilderWithGenerics2.java
@@ -20,6 +20,8 @@ public class SuperBuilderWithGenerics2 {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items == null))

             this.items = new java.util.ArrayList<String>();

         this.items.addAll(items);

diff --git a/test/transform/resource/after-ecj/SuperBuilderWithGenericsAndToBuilder.java b/test/transform/resource/after-ecj/SuperBuilderWithGenericsAndToBuilder.java
index 457104ef..8b26e439 100644
--- a/test/transform/resource/after-ecj/SuperBuilderWithGenericsAndToBuilder.java
+++ b/test/transform/resource/after-ecj/SuperBuilderWithGenericsAndToBuilder.java
@@ -33,6 +33,8 @@ public class SuperBuilderWithGenericsAndToBuilder {
         return self();

       }

       public @java.lang.SuppressWarnings("all") B items(final java.util.Map<? extends Integer, ? extends String> items) {

+        if ((items == null))

+            throw new java.lang.NullPointerException("items cannot be null");

         if ((this.items$key == null))

             {

               this.items$key = new java.util.ArrayList<Integer>();

diff --git a/test/transform/resource/after-ecj/SuperBuilderWithPrefixes.java b/test/transform/resource/after-ecj/SuperBuilderWithPrefixes.java
index 51abbca4..e3b5baeb 100644
--- a/test/transform/resource/after-ecj/SuperBuilderWithPrefixes.java
+++ b/test/transform/resource/after-ecj/SuperBuilderWithPrefixes.java
@@ -23,6 +23,8 @@
       return self();
     }
     public @java.lang.SuppressWarnings("all") B items(final java.util.Collection<? extends String> items) {
+      if ((items == null))
+          throw new java.lang.NullPointerException("items cannot be null");
       if ((this.items == null))
           this.items = new java.util.ArrayList<String>();
       this.items.addAll(items);