#1796 - ENH: add query.fetchCache(path) ... for explicitly building part of graph from L2 cache

src/main/java/io/ebean/FetchConfig.java

@@ -148,6 +148,8 @@ public class FetchConfig implements Serializable {
 
   private boolean queryAll;
 
+  private boolean cache;
+
   /**
    * Construct the fetch configuration object.
    */
@@ -188,6 +190,17 @@ public class FetchConfig implements Serializable {
     return this;
   }
 
+  /**
+   * Eagerly fetch the beans fetching the beans from the L2 bean cache
+   * and using the DB for beans not in the cache.
+   */
+  public FetchConfig cache() {
+    this.cache = true;
+    this.queryBatchSize = 0;
+    this.queryAll = true;
+    return this;
+  }
+
   /**
    * Eagerly fetch the beans in this path as a separate query (rather than as
    * part of the main query).
@@ -247,6 +260,13 @@ public class FetchConfig implements Serializable {
     return queryAll;
   }
 
+  /**
+   * Return true if this uses L2 bean cache.
+   */
+  public boolean isCache() {
+    return cache;
+  }
+
   @Override
   public boolean equals(Object o) {
     if (this == o) return true;
@@ -255,6 +275,7 @@ public class FetchConfig implements Serializable {
     FetchConfig that = (FetchConfig) o;
     if (lazyBatchSize != that.lazyBatchSize) return false;
     if (queryBatchSize != that.queryBatchSize) return false;
+    if (cache != that.cache) return false;
     return queryAll == that.queryAll;
   }
 
@@ -263,6 +284,7 @@ public class FetchConfig implements Serializable {
     int result = lazyBatchSize;
     result = 92821 * result + queryBatchSize;
     result = 92821 * result + (queryAll ? 1 : 0);
+    result = 92821 * result + (cache ? 1 : 0);
     return result;
   }
 }

src/main/java/io/ebean/FetchGroupBuilder.java

@@ -67,12 +67,26 @@ public interface FetchGroupBuilder<T> {
   @Nonnull
   FetchGroupBuilder<T> fetchQuery(String path);
 
+  /**
+   * Fetch the path including all its properties using L2 cache.
+   * Cache misses fallback to fetchQuery().
+   */
+  @Nonnull
+  FetchGroupBuilder<T> fetchCache(String path);
+
   /**
    * Fetch the path including specified properties using a query join.
    */
   @Nonnull
   FetchGroupBuilder<T> fetchQuery(String path, String properties);
 
+  /**
+   * Fetch the path including specified properties using L2 cache.
+   * Cache misses fallback to fetchQuery().
+   */
+  @Nonnull
+  FetchGroupBuilder<T> fetchCache(String path, String properties);
+
   /**
    * Fetch the path including all its properties lazily.
    */

src/main/java/io/ebean/Query.java

@@ -501,6 +501,14 @@ public interface Query<T> {
    */
   Query<T> fetchQuery(String path, String fetchProperties);
 
+  /**
+   * Fetch the path and properties using L2 bean cache.
+   *
+   * @param path            The path of the beans we are fetching from L2 cache.
+   * @param fetchProperties The properties that should be loaded.
+   */
+  Query<T> fetchCache(String path, String fetchProperties);
+
   /**
    * Fetch the path and properties lazily (via batch lazy loading).
    * <p>
@@ -587,6 +595,11 @@ public interface Query<T> {
    */
   Query<T> fetchQuery(String path);
 
+  /**
+   * Fetch the path eagerly using L2 cache.
+   */
+  Query<T> fetchCache(String path);
+
   /**
    * Fetch the path lazily (via batch lazy loading).
    * <p>

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

@@ -95,13 +95,10 @@ public final class EntityBeanIntercept implements Serializable {
   private final byte[] flags;
 
   private boolean fullyLoadedBean;
-
+  private boolean loadedFromCache;
   private Object[] origValues;
-
   private Exception[] loadErrors;
-
   private int lazyLoadProperty = -1;
-
   private Object ownerId;
   private int sortOrder;
 
@@ -311,6 +308,22 @@ public final class EntityBeanIntercept implements Serializable {
     }
   }
 
+  /**
+   * Set true when the bean has been loaded from L2 bean cache.
+   * The effect of this is that we should skip the cache if there
+   * is subsequent lazy loading (bean cache partially populated).
+   */
+  public void setLoadedFromCache(boolean loadedFromCache) {
+    this.loadedFromCache = loadedFromCache;
+  }
+
+  /**
+   * Return true if this bean was loaded from L2 bean cache.
+   */
+  public boolean isLoadedFromCache() {
+    return loadedFromCache;
+  }
+
   /**
    * Return true if the bean should be treated as readOnly. If a setter method
    * is called when it is readOnly an Exception is thrown.
@@ -780,7 +793,7 @@ public final class EntityBeanIntercept implements Serializable {
   }
 
   public boolean[] getLoaded() {
-    boolean[] ret= new boolean[flags.length];
+    boolean[] ret = new boolean[flags.length];
     for (int i = 0; i < ret.length; i++) {
       ret[i] = (flags[i] & FLAG_LOADED_PROP) != 0;
     }

src/main/java/io/ebeaninternal/api/LoadBeanRequest.java

@@ -23,11 +23,14 @@ public class LoadBeanRequest extends LoadRequest {
 
   private final boolean loadCache;
 
+  private boolean loadedFromCache;
+
   /**
    * Construct for lazy load request.
    */
-  public LoadBeanRequest(LoadBeanBuffer LoadBuffer, String lazyLoadProperty, boolean loadCache) {
-    this(LoadBuffer, null, true, lazyLoadProperty, loadCache);
+  public LoadBeanRequest(LoadBeanBuffer LoadBuffer, EntityBeanIntercept ebi, boolean loadCache) {
+    this(LoadBuffer, null, true, ebi.getLazyLoadProperty(), loadCache);
+    this.loadedFromCache = ebi.isLoadedFromCache();
   }
 
   /**
@@ -52,11 +55,17 @@ public class LoadBeanRequest extends LoadRequest {
     return loadBuffer.getBeanDescriptor().getBeanType();
   }
 
+  /**
+   * Return true if the beans invoking lazy loading were previously loaded from cache.
+   */
+  public boolean isLoadedFromCache() {
+    return loadedFromCache;
+  }
+
   private boolean isLoadCache() {
     return loadCache;
   }
 
-
   public String getDescription() {
     return "path:" + loadBuffer.getFullPath() + " batch:" + batch.size();
   }

src/main/java/io/ebeaninternal/server/cache/CachedBeanDataToBean.java

@@ -13,6 +13,8 @@ public class CachedBeanDataToBean {
   public static void load(BeanDescriptor<?> desc, EntityBean bean, CachedBeanData cacheBeanData, PersistenceContext context) {
 
     EntityBeanIntercept ebi = bean._ebean_getIntercept();
+    // any future lazy loading skips L2 bean cache
+    ebi.setLoadedFromCache(true);
 
     BeanProperty idProperty = desc.getIdProperty();
     if (desc.getInheritInfo() != null) {

src/main/java/io/ebeaninternal/server/core/DefaultBeanLoader.java

@@ -1,5 +1,6 @@
 package io.ebeaninternal.server.core;
 
+import io.ebean.CacheMode;
 import io.ebean.ExpressionList;
 import io.ebean.Transaction;
 import io.ebean.bean.BeanCollection;
@@ -38,10 +39,6 @@ class DefaultBeanLoader {
     this.onIterateUseExtraTxn = server.getDatabasePlatform().useExtraTransactionOnIterateSecondaryQueries();
   }
 
-  void refreshMany(EntityBean parentBean, String propertyName) {
-    refreshMany(parentBean, propertyName, null);
-  }
-
   void loadMany(LoadManyRequest loadRequest) {
 
     SpiQuery<?> query = loadRequest.createQuery(server);
@@ -57,8 +54,8 @@ class DefaultBeanLoader {
     loadManyInternal(parentBean, propertyName, null, false, onlyIds);
   }
 
-  private void refreshMany(EntityBean parentBean, String propertyName, Transaction t) {
-    loadManyInternal(parentBean, propertyName, t, true, false);
+  void refreshMany(EntityBean parentBean, String propertyName) {
+    loadManyInternal(parentBean, propertyName, null, true, false);
   }
 
   private void loadManyInternal(EntityBean parentBean, String propertyName, Transaction t, boolean refresh, boolean onlyIds) {
@@ -159,6 +156,9 @@ class DefaultBeanLoader {
 
     SpiQuery<?> query = server.createQuery(loadRequest.getBeanType());
     loadRequest.configureQuery(query, idList);
+    if (loadRequest.isLoadedFromCache()) {
+      query.setBeanCacheMode(CacheMode.PUT);
+    }
 
     List<?> list = executeQuery(loadRequest, query);
     loadRequest.postLoad(list);

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

@@ -570,37 +570,31 @@ public final class DefaultServer implements SpiServer, SpiEbeanServer {
 
   @Override
   public void refreshMany(Object parentBean, String propertyName) {
-
     beanLoader.refreshMany(checkEntityBean(parentBean), propertyName);
   }
 
   @Override
   public void loadMany(LoadManyRequest loadRequest) {
-
     beanLoader.loadMany(loadRequest);
   }
 
   @Override
   public void loadMany(BeanCollection<?> bc, boolean onlyIds) {
-
     beanLoader.loadMany(bc, onlyIds);
   }
 
   @Override
   public void refresh(Object bean) {
-
     beanLoader.refresh(checkEntityBean(bean));
   }
 
   @Override
   public void loadBean(LoadBeanRequest loadRequest) {
-
     beanLoader.loadBean(loadRequest);
   }
 
   @Override
   public void loadBean(EntityBeanIntercept ebi) {
-
     beanLoader.loadBean(ebi);
   }
 

src/main/java/io/ebeaninternal/server/core/OrmQueryRequest.java

@@ -97,6 +97,7 @@ public final class OrmQueryRequest<T> extends BeanRequest implements SpiOrmQuery
     this.queryEngine = queryEngine;
     this.query = query;
     this.readOnly = query.isReadOnly();
+    this.persistenceContext = query.getPersistenceContext();
   }
 
   public PersistenceException translate(String bindLog, String sql, SQLException e) {

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptor.java

@@ -2316,6 +2316,13 @@ public class BeanDescriptor<T> implements BeanType<T>, STreeType {
     return idBinder.convertSetId(idValue, bean);
   }
 
+  /**
+   * Set the Id value to the bean (without type conversion).
+   */
+  public void setId(Object idValue, EntityBean bean) {
+    idProperty.setValueIntercept(bean, idValue);
+  }
+
   @Override
   public Property getProperty(String propName) {
     return findProperty(propName);

src/main/java/io/ebeaninternal/server/deploy/BeanDescriptorCacheHelp.java

@@ -675,25 +675,30 @@ final class BeanDescriptorCacheHelp<T> {
    */
   EntityBean loadBeanDirect(Object id, Boolean readOnly, CachedBeanData data, PersistenceContext context) {
 
+    id = desc.convertId(id);
+    EntityBean bean = null;
     if (context == null) {
       context = new DefaultPersistenceContext();
+    } else {
+      bean = (EntityBean)desc.contextGet(context, id);
+    }
+
+    if (bean == null) {
+      bean = desc.createEntityBean();
+      desc.setId(id, bean);
+      desc.contextPut(context, id, bean);
+
+      EntityBeanIntercept ebi = bean._ebean_getIntercept();
+      // Not using loadContext here so no batch lazy loading for these beans
+      ebi.setBeanLoader(desc.getEbeanServer());
+      if (Boolean.TRUE.equals(readOnly)) {
+        ebi.setReadOnly(true);
+      }
+      ebi.setPersistenceContext(context);
     }
 
-    EntityBean bean = desc.createEntityBean();
-    id = desc.convertSetId(id, bean);
     CachedBeanDataToBean.load(desc, bean, data, context);
 
-    EntityBeanIntercept ebi = bean._ebean_getIntercept();
-
-    // Not using a loadContext for beans coming out of L2 cache
-    // so that means no batch lazy loading for these beans
-    ebi.setBeanLoader(desc.getEbeanServer());
-    if (Boolean.TRUE.equals(readOnly)) {
-      ebi.setReadOnly(true);
-    }
-    ebi.setPersistenceContext(context);
-    desc.contextPut(context, id, bean);
-
     if (desc.isReadAuditing()) {
       desc.readAuditBean("l2", "", bean);
     }

src/main/java/io/ebeaninternal/server/deploy/id/IdBinderFactory.java

@@ -24,11 +24,9 @@ public class IdBinderFactory {
    * Create the IdConvertSet for the given type of Id properties.
    */
   public IdBinder createIdBinder(BeanProperty id) {
-
     if (id == null) {
       // for report type beans that don't need an id
       return EMPTY;
-
     }
     if (id.isEmbedded()) {
       return new IdBinderEmbedded(idInExpandedForm, (BeanPropertyAssocOne<?>) id);

src/main/java/io/ebeaninternal/server/loadcontext/DLoadBeanContext.java

@@ -191,7 +191,7 @@ class DLoadBeanContext extends DLoadBaseContext implements LoadBeanContext {
         }
       }
 
-      LoadBeanRequest req = new LoadBeanRequest(this, ebi.getLazyLoadProperty(), context.hitCache);
+      LoadBeanRequest req = new LoadBeanRequest(this, ebi, context.hitCache);
       context.desc.getEbeanServer().loadBean(req);
     }
   }

src/main/java/io/ebeaninternal/server/query/DFetchGroupBuilder.java

@@ -11,6 +11,8 @@ import io.ebeaninternal.server.querydefn.SpiFetchGroup;
  */
 class DFetchGroupBuilder<T> implements FetchGroupBuilder<T> {
 
+  private static final FetchConfig FETCH_CACHE = new FetchConfig().cache();
+
   private static final FetchConfig FETCH_QUERY = new FetchConfig().query();
 
   private static final FetchConfig FETCH_LAZY = new FetchConfig().lazy();
@@ -61,6 +63,12 @@ class DFetchGroupBuilder<T> implements FetchGroupBuilder<T> {
     return this;
   }
 
+  @Override
+  public FetchGroupBuilder<T> fetchCache(String path) {
+    detail.fetch(path, null, FETCH_CACHE);
+    return this;
+  }
+
   @Override
   public FetchGroupBuilder<T> fetchLazy(String path) {
     detail.fetch(path, null, FETCH_LAZY);
@@ -79,6 +87,12 @@ class DFetchGroupBuilder<T> implements FetchGroupBuilder<T> {
     return this;
   }
 
+  @Override
+  public FetchGroupBuilder<T> fetchCache(String path, String properties) {
+    detail.fetch(path, properties, FETCH_CACHE);
+    return this;
+  }
+
   @Override
   public FetchGroupBuilder<T> fetchLazy(String path, String properties) {
     detail.fetch(path, properties, FETCH_LAZY);

src/main/java/io/ebeaninternal/server/query/DefaultFetchGroupQuery.java

@@ -43,6 +43,8 @@ import java.util.function.Predicate;
  */
 class DefaultFetchGroupQuery<T> implements SpiFetchGroupQuery<T> {
 
+  private static final FetchConfig FETCH_CACHE = new FetchConfig().cache();
+
   private static final FetchConfig FETCH_QUERY = new FetchConfig().query();
 
   private static final FetchConfig FETCH_LAZY = new FetchConfig().lazy();
@@ -76,6 +78,11 @@ class DefaultFetchGroupQuery<T> implements SpiFetchGroupQuery<T> {
     return fetch(property, null, FETCH_QUERY);
   }
 
+  @Override
+  public Query<T> fetchCache(String property) {
+    return fetch(property, null, FETCH_CACHE);
+  }
+
   @Override
   public Query<T> fetchLazy(String property) {
     return fetch(property, null, FETCH_LAZY);
@@ -96,6 +103,11 @@ class DefaultFetchGroupQuery<T> implements SpiFetchGroupQuery<T> {
     return fetch(property, columns, FETCH_QUERY);
   }
 
+  @Override
+  public Query<T> fetchCache(String property, String columns) {
+    return fetch(property, columns, FETCH_CACHE);
+  }
+
   @Override
   public Query<T> fetchLazy(String property, String columns) {
     return fetch(property, columns, FETCH_LAZY);

src/main/java/io/ebeaninternal/server/querydefn/DefaultOrmQuery.java

@@ -79,6 +79,8 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
 
   private static final String DEFAULT_QUERY_NAME = "default";
 
+  private static final FetchConfig FETCH_CACHE = new FetchConfig().cache();
+
   private static final FetchConfig FETCH_QUERY = new FetchConfig().query();
 
   private static final FetchConfig FETCH_LAZY = new FetchConfig().lazy();
@@ -1405,6 +1407,10 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
     return fetch(property, null, FETCH_QUERY);
   }
 
+  public Query<T> fetchCache(String property) {
+    return fetch(property, null, FETCH_CACHE);
+  }
+
   @Override
   public Query<T> fetchLazy(String property) {
     return fetch(property, null, FETCH_LAZY);
@@ -1425,6 +1431,11 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
     return fetch(property, columns, FETCH_QUERY);
   }
 
+  @Override
+  public Query<T> fetchCache(String property, String columns) {
+    return fetch(property, columns, FETCH_CACHE);
+  }
+
   @Override
   public Query<T> fetchLazy(String property, String columns) {
     return fetch(property, columns, FETCH_LAZY);

src/main/java/io/ebeaninternal/server/querydefn/OrmQueryProperties.java

@@ -107,6 +107,9 @@ public class OrmQueryProperties implements Serializable {
     this.readOnly = response.readOnly;
     if (fetchConfig != null) {
       this.fetchConfig = fetchConfig;
+      if (fetchConfig.isCache()) {
+        this.cache = true;
+      }
     } else {
       this.fetchConfig = response.fetchConfig;
     }