#2208 - When using fetchCache() with a single id / findOne ... doesn't hit L2 cache

Plus #2207 ENH: Query beans add support for nested FetchGroup

ebean-core/src/main/java/io/ebeaninternal/api/CacheIdLookup.java

@@ -1,52 +1,25 @@
 package io.ebeaninternal.api;
 
-import io.ebeaninternal.server.expression.IdInExpression;
-
-import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashSet;
 import java.util.List;
-import java.util.Set;
 
 /**
- * Used for bean cache lookup with where ids in expression.
+ * Process Cache lookup by Id(s).
  */
-public class CacheIdLookup<T> {
-
-  private final IdInExpression idInExpression;
-
-  private int remaining;
-
-  public CacheIdLookup(IdInExpression idInExpression) {
-    this.idInExpression = idInExpression;
-  }
+public interface CacheIdLookup<T> {
 
   /**
-   * Return the Id values for the in expression.
+   * Return the Id values to lookup against the L2 cache.
    */
-  public Collection<?> idValues() {
-    return idInExpression.idValues();
-  }
+  Collection<?> idValues();
 
   /**
-   * Process the hits returning the beans fetched from cache and
-   * adjusting the in expression (to not fetch the hits).
+   * Remove the hits returning the beans fetched from L2 cache.
    */
-  public List<T> removeHits(BeanCacheResult<T> cacheResult) {
+  List<T> removeHits(BeanCacheResult<T> cacheResult);
 
-    Set<Object> hitIds = new HashSet<>();
-    List<T> beans = new ArrayList<>(hitIds.size());
-
-    for (BeanCacheResult.Entry<T> hit : cacheResult.hits()) {
-      hitIds.add(hit.getKey());
-      beans.add(hit.getBean());
-    }
-
-    this.remaining = idInExpression.removeIds(hitIds);
-    return beans;
-  }
-
-  public boolean allHits() {
-    return remaining == 0;
-  }
+  /**
+   * Return true if all beans where found in L2 cache.
+   */
+  boolean allHits();
 }

ebean-core/src/main/java/io/ebeaninternal/api/CacheIdLookupMany.java

@@ -0,0 +1,55 @@
+package io.ebeaninternal.api;
+
+import io.ebeaninternal.server.expression.IdInExpression;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+/**
+ * Used for bean cache lookup with where ids in expression.
+ */
+public class CacheIdLookupMany<T> implements CacheIdLookup<T> {
+
+  private final IdInExpression idInExpression;
+
+  private int remaining;
+
+  public CacheIdLookupMany(IdInExpression idInExpression) {
+    this.idInExpression = idInExpression;
+  }
+
+  /**
+   * Return the Id values for the in expression.
+   */
+  @Override
+  public Collection<?> idValues() {
+    return idInExpression.idValues();
+  }
+
+  /**
+   * Process the hits returning the beans fetched from cache and
+   * adjusting the in expression (to not fetch the hits).
+   */
+  @Override
+  public List<T> removeHits(BeanCacheResult<T> cacheResult) {
+
+    Set<Object> hitIds = new HashSet<>();
+    List<T> beans = new ArrayList<>(hitIds.size());
+
+    for (BeanCacheResult.Entry<T> hit : cacheResult.hits()) {
+      hitIds.add(hit.getKey());
+      beans.add(hit.getBean());
+    }
+
+    this.remaining = idInExpression.removeIds(hitIds);
+    return beans;
+  }
+
+  @Override
+  public boolean allHits() {
+    return remaining == 0;
+  }
+}

ebean-core/src/main/java/io/ebeaninternal/api/CacheIdLookupSingle.java

@@ -0,0 +1,38 @@
+package io.ebeaninternal.api;
+
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+/**
+ * Used for bean cache lookup with a single id value.
+ */
+public class CacheIdLookupSingle<T> implements CacheIdLookup<T> {
+
+  private final Object idValue;
+  private boolean found;
+
+  public CacheIdLookupSingle(Object idValue) {
+    this.idValue = idValue;
+  }
+
+  @Override
+  public Collection<?> idValues() {
+    return Collections.singleton(idValue);
+  }
+
+  @Override
+  public List<T> removeHits(BeanCacheResult<T> cacheResult) {
+    final List<BeanCacheResult.Entry<T>> hits = cacheResult.hits();
+    if (hits.size() == 1) {
+      found = true;
+      return Collections.singletonList(hits.get(0).getBean());
+    }
+    return Collections.emptyList();
+  }
+
+  @Override
+  public boolean allHits() {
+    return found;
+  }
+}

ebean-core/src/main/java/io/ebeaninternal/api/SpiQueryFetch.java

@@ -1,6 +1,7 @@
 package io.ebeaninternal.api;
 
 import io.ebean.FetchConfig;
+import io.ebeaninternal.server.querydefn.OrmQueryDetail;
 
 import java.util.Set;
 
@@ -19,4 +20,8 @@ public interface SpiQueryFetch {
    */
   void fetchProperties(String name, Set<String> properties, FetchConfig config);
 
+  /**
+   * Add a nested fetch graph.
+   */
+  void addNested(String name, OrmQueryDetail nestedDetail, FetchConfig config);
 }

ebean-core/src/main/java/io/ebeaninternal/server/query/DefaultFetchGroupQuery.java

@@ -644,4 +644,9 @@ class DefaultFetchGroupQuery<T> implements SpiFetchGroupQuery<T>, SpiQueryFetch
   public void fetchProperties(String property, Set<String> columns, FetchConfig config) {
     detail.fetchProperties(property, columns, config);
   }
+
+  @Override
+  public void addNested(String name, OrmQueryDetail nestedDetail, FetchConfig config) {
+    detail.addNested(name, nestedDetail, config);
+  }
 }

ebean-core/src/main/java/io/ebeaninternal/server/querydefn/DefaultOrmQuery.java

@@ -35,6 +35,8 @@ import io.ebean.plugin.BeanType;
 import io.ebeaninternal.api.BindParams;
 import io.ebeaninternal.api.CQueryPlanKey;
 import io.ebeaninternal.api.CacheIdLookup;
+import io.ebeaninternal.api.CacheIdLookupMany;
+import io.ebeaninternal.api.CacheIdLookupSingle;
 import io.ebeaninternal.api.HashQuery;
 import io.ebeaninternal.api.ManyWhereJoins;
 import io.ebeaninternal.api.NaturalKeyQueryData;
@@ -740,10 +742,14 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
       return null;
     }
     List<SpiExpression> underlyingList = whereExpressions.getUnderlyingList();
-    if (underlyingList.size() == 1) {
+    if (underlyingList.isEmpty()) {
+      if (id != null) {
+        return new CacheIdLookupSingle<>(id);
+      }
+    } else if (underlyingList.size() == 1) {
       SpiExpression singleExpression = underlyingList.get(0);
       if (singleExpression instanceof IdInExpression) {
-        return new CacheIdLookup<>((IdInExpression) singleExpression);
+        return new CacheIdLookupMany<>((IdInExpression) singleExpression);
       }
     }
     return null;
@@ -1412,6 +1418,11 @@ public class DefaultOrmQuery<T> implements SpiQuery<T> {
     detail.fetchProperties(path, other);
   }
 
+  @Override
+  public void addNested(String name, OrmQueryDetail nestedDetail, FetchConfig config) {
+    detail.addNested(name, nestedDetail, config);
+  }
+
   @Override
   public Query<T> select(String columns) {
     detail.select(columns);

ebean-core/src/main/java/io/ebeaninternal/server/querydefn/OrmQueryProperties.java

@@ -120,8 +120,8 @@ public class OrmQueryProperties implements Serializable {
     this.parentPath = SplitName.parent(path);
     this.allProperties = other.allProperties;
     this.included = other.included;
-    this.cache = other.cache;
     this.fetchConfig = fetchConfig;
+    this.cache = fetchConfig.isCache();
   }
 
   /**