#1804 - Kotlin: Generating collection with wildcard type - Get error BeanNotRegisteredException: Error with association to [null] from [...Foo.manyProperty]. Is null registered?

src/test/java/org/tests/o2m/OmBasicParent.java

@@ -0,0 +1,60 @@
+package org.tests.o2m;
+
+import javax.persistence.Entity;
+import javax.persistence.Id;
+import javax.persistence.OneToMany;
+import javax.persistence.Version;
+import java.util.List;
+
+import static javax.persistence.CascadeType.ALL;
+
+@Entity
+public class OmBasicParent {
+
+  @Id
+  private long id;
+
+  private final String name;
+
+  @Version
+  private long version;
+
+  /**
+   * Not really sensible Java code here but Kotlin can generate
+   * a collection type that looks like this
+   */
+  @OneToMany(cascade = ALL, mappedBy = "parent")
+  private List<? extends OmBasicChild> children;
+
+  public OmBasicParent(String name) {
+    this.name = name;
+  }
+
+  public long getId() {
+    return id;
+  }
+
+  public void setId(long id) {
+    this.id = id;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public long getVersion() {
+    return version;
+  }
+
+  public void setVersion(long version) {
+    this.version = version;
+  }
+
+  public List<? extends OmBasicChild> getChildren() {
+    return children;
+  }
+
+  public void setChildren(List<? extends OmBasicChild> children) {
+    this.children = children;
+  }
+}