#535 - Bean lazy loading can execute an extra query when one of the lazy loaded beans has been deleted

src/main/java/com/avaje/ebean/bean/EntityBeanIntercept.java

@@ -1,5 +1,10 @@
 package com.avaje.ebean.bean;
 
+import com.avaje.ebean.Ebean;
+import com.avaje.ebean.ValuePair;
+
+import javax.persistence.EntityNotFoundException;
+import javax.persistence.PersistenceException;
 import java.beans.PropertyChangeEvent;
 import java.beans.PropertyChangeListener;
 import java.beans.PropertyChangeSupport;
@@ -11,12 +16,6 @@ import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Set;
 
-import javax.persistence.EntityNotFoundException;
-import javax.persistence.PersistenceException;
-
-import com.avaje.ebean.Ebean;
-import com.avaje.ebean.ValuePair;
-
 /**
  * This is the object added to every entity bean using byte code enhancement.
  * <p>
@@ -92,6 +91,8 @@ public final class EntityBeanIntercept implements Serializable {
 
   private int lazyLoadProperty = -1;
 
+  private Object ownerId;
+
   /**
    * Create a intercept with a given entity.
    * <p>
@@ -349,11 +350,22 @@ public final class EntityBeanIntercept implements Serializable {
    * lazy loading and this bean might not be used by the client code at all.
    * Instead we will fail as soon as the client code tries to use this bean.
    * </p>
+   * @param lazyLoadPropertyIndex the property that is expected to be loaded
    */
-  public void checkLazyLoadFailure() {
-    if (lazyLoadProperty != -1) {
-      this.lazyLoadFailure = true;
+  public boolean isLazyLoadFailure(int lazyLoadPropertyIndex) {
+    if (lazyLoadProperty != -1 || !isLoadedProperty(lazyLoadPropertyIndex)) {
+      lazyLoadFailure = true;
+      return true;
     }
+    lazyLoadFailure = false;
+    return false;
+  }
+
+  /**
+   * Set the Id of the owner bean.
+   */
+  public void setOwnerId(Object ownerId) {
+    this.ownerId = ownerId;
   }
 
   /**
@@ -748,7 +760,7 @@ public final class EntityBeanIntercept implements Serializable {
 
     if (lazyLoadFailure) {
       // failed when batch lazy loaded by another bean in the batch
-      throw new EntityNotFoundException("Bean has been deleted - lazy loading failed");
+      throw new EntityNotFoundException("Lazy loading failed on type:" + owner.getClass().getName() + " id:" + ownerId + " - Bean has been deleted");
     }
 
     if (lazyLoadProperty == -1) {
@@ -763,7 +775,7 @@ public final class EntityBeanIntercept implements Serializable {
 
       if (lazyLoadFailure) {
         // failed when lazy loading this bean
-        throw new EntityNotFoundException("Bean has been deleted - lazy loading failed");
+        throw new EntityNotFoundException("Lazy loading failed on type:" + owner.getClass().getName() + " id:" + ownerId + " - Bean has been deleted.");
       }
 
       // bean should be loaded and intercepting now. setLoaded() has

src/main/java/com/avaje/ebeaninternal/api/LoadBeanRequest.java

@@ -4,6 +4,8 @@ import com.avaje.ebean.bean.EntityBean;
 import com.avaje.ebean.bean.EntityBeanIntercept;
 import com.avaje.ebeaninternal.server.core.OrmQueryRequest;
 import com.avaje.ebeaninternal.server.deploy.BeanDescriptor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -13,10 +15,14 @@ import java.util.List;
  */
 public class LoadBeanRequest extends LoadRequest {
 
+  private static final Logger logger = LoggerFactory.getLogger(LoadBeanRequest.class);
+
   private final List<EntityBeanIntercept> batch;
 
   private final LoadBeanBuffer loadBuffer;
 
+  private final int lazyLoadPropertyIndex;
+
   private final String lazyLoadProperty;
 
   private final boolean loadCache;
@@ -24,21 +30,24 @@ public class LoadBeanRequest extends LoadRequest {
   /**
    * Construct for lazy load request.
    */
-  public LoadBeanRequest(LoadBeanBuffer LoadBuffer, String lazyLoadProperty, boolean loadCache) {
-    this(LoadBuffer, null, true, lazyLoadProperty, loadCache);
+  public LoadBeanRequest(LoadBeanBuffer LoadBuffer, int lazyLoadPropertyIndex, String lazyLoadProperty, boolean loadCache) {
+    this(LoadBuffer, null, true, lazyLoadPropertyIndex, lazyLoadProperty, loadCache);
   }
 
   /**
    * Construct for secondary query.
    */
   public LoadBeanRequest(LoadBeanBuffer LoadBuffer, OrmQueryRequest<?> parentRequest) {
-    this(LoadBuffer, parentRequest, false, null, false);
+    this(LoadBuffer, parentRequest, false, -1, null, false);
   }
 
-  private LoadBeanRequest(LoadBeanBuffer loadBuffer, OrmQueryRequest<?> parentRequest, boolean lazy, String lazyLoadProperty, boolean loadCache) {
+  private LoadBeanRequest(LoadBeanBuffer loadBuffer, OrmQueryRequest<?> parentRequest, boolean lazy,
+                          int lazyLoadPropertyIndex, String lazyLoadProperty, boolean loadCache) {
+
     super(parentRequest, lazy);
     this.loadBuffer = loadBuffer;
     this.batch = loadBuffer.getBatch();
+    this.lazyLoadPropertyIndex = lazyLoadPropertyIndex;
     this.lazyLoadProperty = lazyLoadProperty;
     this.loadCache = loadCache;
   }
@@ -143,10 +152,20 @@ public class LoadBeanRequest extends LoadRequest {
       }
     }
 
-    for (int i = 0; i < batch.size(); i++) {
-      // Check if the underlying row in DB was deleted. Mark this bean as 'failed' if
-      // necessary but allow processing to continue until it is accessed by client code
-      batch.get(i).checkLazyLoadFailure();
+    if (lazyLoadPropertyIndex > -1) {
+      // this is a lazy loading query so check for lazy loading failure (due to deleted rows)
+      for (int i = 0; i < batch.size(); i++) {
+        // check if the underlying row in DB was deleted. Mark the bean as 'failed' if
+        // necessary but allow processing to continue until it is accessed by client code
+        EntityBeanIntercept ebi = batch.get(i);
+        // all beans in the batch should have this property loaded now
+        if (ebi.isLazyLoadFailure(lazyLoadPropertyIndex)) {
+          BeanDescriptor<?> desc = loadBuffer.getBeanDescriptor();
+          Object beanId = desc.getId(ebi.getOwner());
+          ebi.setOwnerId(beanId);
+          logger.info("Lazy loading unsuccessful for type:" + desc.getName() + " id:" + beanId + " - expecting when bean has been deleted");
+        }
+      }
     }
   }
 }

src/main/java/com/avaje/ebeaninternal/api/LoadManyRequest.java

@@ -183,7 +183,7 @@ public class LoadManyRequest extends LoadRequest {
         if (logger.isDebugEnabled()) {
           EntityBean ownerBean = bc.getOwnerBean();
           Object parentId = desc.getId(ownerBean);
-          logger.debug("BeanCollection after lazy load was empty. type[" + ownerBean.getClass() + "] id[" + parentId + "] owner[" + ownerBean + "]");
+          logger.debug("BeanCollection after lazy load was empty. type:" + ownerBean.getClass().getName() + " id:" + parentId + " owner:" + ownerBean);
         }
       } else if (isLoadCache()) {
         Object parentId = desc.getId(bc.getOwnerBean());

src/main/java/com/avaje/ebeaninternal/server/core/DefaultBeanLoader.java

@@ -85,7 +85,7 @@ public class DefaultBeanLoader {
 
     SpiQuery<?> query = loadRequest.createQuery(server, batchSize);
 
-    executeLazyLoadQuery(loadRequest, query);
+    executeQuery(loadRequest, query);
 
     loadRequest.postLoad();
 
@@ -214,7 +214,7 @@ public class DefaultBeanLoader {
       query.where().idIn(idList);
     }
 
-    List<?> list = executeLazyLoadQuery(loadRequest, query);
+    List<?> list = executeQuery(loadRequest, query);
 
     loadRequest.postLoad(list);
 
@@ -225,7 +225,7 @@ public class DefaultBeanLoader {
   /**
    * Execute the lazy load query taking into account MySql transaction oddness.
    */
-  private List<?> executeLazyLoadQuery(LoadRequest loadRequest, SpiQuery<?> query) {
+  private List<?> executeQuery(LoadRequest loadRequest, SpiQuery<?> query) {
     if (onIterateUseExtraTxn && loadRequest.isParentFindIterate()) {
       // MySql - we need a different transaction to execute the secondary query
       SpiTransaction extraTxn = server.createQueryTransaction();

src/main/java/com/avaje/ebeaninternal/server/loadcontext/DLoadBeanContext.java

@@ -190,7 +190,7 @@ public class DLoadBeanContext extends DLoadBaseContext implements LoadBeanContex
         }
       }
 
-      LoadBeanRequest req = new LoadBeanRequest(this, ebi.getLazyLoadProperty(), context.hitCache);
+      LoadBeanRequest req = new LoadBeanRequest(this, ebi.getLazyLoadPropertyIndex(), ebi.getLazyLoadProperty(), context.hitCache);
       context.desc.getEbeanServer().loadBean(req);
     }