#2418 #2420 BeanState.loadErrors() returns empty map

Change Database.beanState() to throw IllegalArgumentException when bean isn't an entity bean

ebean-api/src/main/java/io/ebean/BeanState.java

@@ -138,7 +138,6 @@ public interface BeanState {
   /**
    * Returns a map with load errors.
    */
-  @Nullable
   Map<String, Exception> loadErrors();
 
   /**

ebean-api/src/main/java/io/ebean/bean/EntityBeanIntercept.java

@@ -9,11 +9,7 @@ import javax.persistence.PersistenceException;
 import java.io.Serializable;
 import java.math.BigDecimal;
 import java.net.URL;
-import java.util.Arrays;
+import java.util.*;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
-import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 
@@ -1164,7 +1160,7 @@ public final class EntityBeanIntercept implements Serializable {
    */
   public Map<String, Exception> getLoadErrors() {
     if (loadErrors == null) {
-      return null;
+      return Collections.emptyMap();
     }
     Map<String, Exception> ret = null;
     int len = getPropertyLength();

ebean-core/src/main/java/io/ebeaninternal/server/core/DefaultServer.java

@@ -497,8 +497,7 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
     if (bean instanceof EntityBean) {
       return new DefaultBeanState((EntityBean) bean);
     }
-    // Not an entity bean
+    throw new IllegalArgumentException("Bean is not an entity bean");
-    return null; // throw new IllegalArgumentException("Bean is not an entity bean");
   }
 
   /**

ebean-test/src/test/java/org/tests/batchload/TestBeanState.java

@@ -16,11 +16,24 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.*;
 
 
-public class TestBeanState extends BaseTestCase {
+class TestBeanState extends BaseTestCase {
 
   @Test
-  public void test() {
+  void invalid() {
+    assertThrows(IllegalArgumentException.class, () -> DB.beanState(new Object()));
+  }
 
+  @Test
+  void loadErrors_when_empty() {
+    ResetBasicData.reset();
+    Customer one = DB.find(Customer.class).setMaxRows(1).findOne();
+    BeanState beanState = DB.beanState(one);
+
+    assertThat(beanState.loadErrors()).isEmpty();
+  }
+
+  @Test
+  void test() {
     ResetBasicData.reset();
 
     List<Customer> custs = DB.find(Customer.class).findList();
@@ -55,8 +68,7 @@ public class TestBeanState extends BaseTestCase {
   }
 
   @Test
-  public void setDisableLazyLoad_expect_lazyLoadingDisabled() {
+  void setDisableLazyLoad_expect_lazyLoadingDisabled() {
-
     ResetBasicData.reset();
 
     List<Customer> custs = DB.find(Customer.class).order("id").findList();
@@ -73,8 +85,7 @@ public class TestBeanState extends BaseTestCase {
   }
 
   @Test
-  public void getChangedProps_when_setManyProperty() {
+  void changedProps_when_setManyProperty() {
-
     ResetBasicData.reset();
 
     Customer customer = DB.find(Customer.class).order("id").setMaxRows(1).findOne();
@@ -87,8 +98,7 @@ public class TestBeanState extends BaseTestCase {
   }
 
   @Test
-  public void getChangedProps_when_setManyProperty_onNewBean() {
+  void changedProps_when_setManyProperty_onNewBean() {
-
     Customer customer = new Customer();
 
     BeanState beanState = DB.beanState(customer);
@@ -107,7 +117,7 @@ public class TestBeanState extends BaseTestCase {
   }
 
   @Test
-  public void readOnly_when_setManyProperty() {
+  void readOnly_when_setManyProperty() {
     Customer customer = new Customer();
     customer.setContacts(new ArrayList<>());
 
@@ -120,7 +130,7 @@ public class TestBeanState extends BaseTestCase {
   }
 
   @Test
-  public void readOnly_when_setProperty() {
+  void readOnly_when_setProperty() {
     Customer customer = new Customer();
     customer.setName("a");