Query cache OOM for too large beans

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

@@ -1,5 +1,6 @@
 package io.ebeaninternal.api;
 
+import io.ebean.bean.EntityBean;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -13,10 +14,23 @@ public final class BindValuesKey {
 
   private final List<Object> values = new ArrayList<>();
 
+  private final SpiEbeanServer server;
+
+  public BindValuesKey(SpiEbeanServer server) {
+    this.server = server;
+  }
+
   /**
    * Add a bind value.
    */
   public BindValuesKey add(Object value) {
+    if (value instanceof EntityBean) {
+      // Only interested in id to keep the memory footprint low
+      Object id = server.beanId(value);
+      if (id != null) {
+        value = id;
+      }
+    }
     values.add(value);
     return this;
   }

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

@@ -1244,7 +1244,7 @@ public final void queryBindKey(BindValuesKey key) {
   public final HashQuery queryHash() {
     // calculateQueryPlanHash is called just after potential AutoTune tuning
     // so queryPlanHash is calculated well before this method is called
-    BindValuesKey bindKey = new BindValuesKey();
+    BindValuesKey bindKey = new BindValuesKey(server);
     queryBindKey(bindKey);
     return new HashQuery(queryPlanKey, bindKey);
   }

ebean-core/src/test/java/io/ebeaninternal/server/expression/RawExpressionTest.java

@@ -70,7 +70,7 @@ public void assert_queryBindHash_isSame(RawExpression exp0, RawExpression exp1)
   }
 
   private BindValuesKey bindKey(RawExpression query) {
-    BindValuesKey bindValuesKey = new BindValuesKey();
+    BindValuesKey bindValuesKey = new BindValuesKey(spiEbeanServer());
     query.queryBindKey(bindValuesKey);
     return bindValuesKey;
   }

ebean-core/src/test/java/io/ebeaninternal/server/querydefn/BindValuesKeyTest.java

@@ -1,19 +1,20 @@
 package io.ebeaninternal.server.querydefn;
 
 import io.ebeaninternal.api.BindValuesKey;
+import io.ebeaninternal.server.deploy.BaseTest;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
-public class BindValuesKeyTest {
+public class BindValuesKeyTest extends BaseTest {
 
   @Test
   public void update_with_null() {
 
-    BindValuesKey hash = new BindValuesKey();
+    BindValuesKey hash = new BindValuesKey(spiEbeanServer());
     hash.add(1).add(null).add("hello");
 
-    BindValuesKey hash2 = new BindValuesKey();
+    BindValuesKey hash2 = new BindValuesKey(spiEbeanServer());
     hash2.add(1).add(null).add("hello");
 
     assertThat(hash).isEqualTo(hash2);
@@ -22,13 +23,13 @@ public void update_with_null() {
   @Test
   public void notEqual() {
 
-    BindValuesKey hash = new BindValuesKey();
+    BindValuesKey hash = new BindValuesKey(spiEbeanServer());
     hash.add(1).add(null).add("hello");
 
-    BindValuesKey hash2 = new BindValuesKey();
+    BindValuesKey hash2 = new BindValuesKey(spiEbeanServer());
     hash2.add(1).add("hello");
 
-    BindValuesKey hash3 = new BindValuesKey();
+    BindValuesKey hash3 = new BindValuesKey(spiEbeanServer());
     hash2.add(1).add(null);
 
     assertThat(hash).isNotEqualTo(hash2);

ebean-core/src/test/java/io/ebeaninternal/server/querydefn/DefaultOrmQueryTest.java

@@ -139,7 +139,7 @@ private <T> void prepare(DefaultOrmQuery<T> q1, DefaultOrmQuery<T> q2) {
   }
 
   private BindValuesKey bindKey(DefaultOrmQuery<Order> query) {
-    BindValuesKey key = new BindValuesKey();
+    BindValuesKey key = new BindValuesKey(spiEbeanServer());
     query.queryBindKey(key);
     return key;
   }

ebean-test/src/test/java/org/tests/model/memleak/MemleakChild.java

@@ -0,0 +1,21 @@
+package org.tests.model.memleak;
+
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+
+/**
+ * Class with @Cache(enableQueryCache = true)
+ *
+ * @author Jonas Fröhler, FOCONIS AG
+ */
+@Entity
+public class MemleakChild {
+
+  @Id
+  Long id;
+
+  String name;
+
+  transient byte[] memConsumer = new byte[1000000];
+
+}

ebean-test/src/test/java/org/tests/model/memleak/MemleakParent.java

@@ -0,0 +1,25 @@
+package org.tests.model.memleak;
+
+import io.ebean.annotation.Cache;
+import jakarta.persistence.Entity;
+import jakarta.persistence.Id;
+import jakarta.persistence.ManyToOne;
+
+/**
+ * Class that holds the {@link MemleakChild}.
+ *
+ * @author Jonas Fröhler, Foconis Analytics GmbH
+ */
+@Entity
+@Cache(enableQueryCache = true)
+public class MemleakParent {
+
+  @Id
+  Long id;
+
+  @ManyToOne()
+  MemleakChild child;
+
+  String name;
+
+}

ebean-test/src/test/java/org/tests/model/memleak/TestQueryCacheHoldsBean.java

@@ -0,0 +1,26 @@
+package org.tests.model.memleak;
+
+import io.ebean.DB;
+import io.ebean.xtest.BaseTestCase;
+import org.junit.jupiter.api.Disabled;
+import org.junit.jupiter.api.Test;
+
+/**
+ * The query cache holds the bean (MemleakChild). If there are "big" beans, then an OOM may occur.
+ *
+ * @author Jonas Fröhler, Foconis Analytics GmbH
+ */
+public class TestQueryCacheHoldsBean extends BaseTestCase {
+
+  @Test
+  @Disabled("Run manually with -Xmx128M")
+  void testQueryCacheHoldsBean() {
+    for (long id = 0; id <= 1000; id++) {
+      DB.find(MemleakParent.class)
+        .where().eq("id", id)
+        .eq("child", DB.reference(MemleakChild.class, id))
+        .setUseQueryCache(true)
+        .findOne();
+    }
+  }
+}