WIP: working toward storing entity instances in a session-local cache.

helenus-core.iml

@@ -11,8 +11,8 @@
     </content>
     <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
-    <orderEntry type="library" name="Maven: io.dropwizard.metrics:metrics-core:3.2.2" level="project" />
-    <orderEntry type="library" scope="TEST" name="Maven: com.github.ben-manes.caffeine:caffeine:2.2.6" level="project" />
+    <orderEntry type="library" name="Maven: com.github.ben-manes.caffeine:caffeine:2.5.3" level="project" />
+    <orderEntry type="library" name="Maven: io.dropwizard.metrics:metrics-core:3.2.3" level="project" />
     <orderEntry type="library" name="Maven: org.scala-lang:scala-library:2.13.0-M1" level="project" />
     <orderEntry type="library" name="Maven: com.datastax.cassandra:cassandra-driver-core:3.3.0" level="project" />
     <orderEntry type="library" name="Maven: io.netty:netty-handler:4.0.47.Final" level="project" />
@@ -20,7 +20,6 @@
     <orderEntry type="library" name="Maven: io.netty:netty-common:4.0.47.Final" level="project" />
     <orderEntry type="library" name="Maven: io.netty:netty-transport:4.0.47.Final" level="project" />
     <orderEntry type="library" name="Maven: io.netty:netty-codec:4.0.47.Final" level="project" />
-    <orderEntry type="library" name="Maven: io.dropwizard.metrics:metrics-core:3.2.2" level="project" />
     <orderEntry type="library" name="Maven: com.github.jnr:jnr-ffi:2.0.7" level="project" />
     <orderEntry type="library" name="Maven: com.github.jnr:jffi:1.2.10" level="project" />
     <orderEntry type="library" scope="RUNTIME" name="Maven: com.github.jnr:jffi:native:1.2.10" level="project" />
@@ -38,6 +37,8 @@
     <orderEntry type="library" name="Maven: org.springframework:spring-core:4.3.10.RELEASE" level="project" />
     <orderEntry type="library" name="Maven: commons-logging:commons-logging:1.2" level="project" />
     <orderEntry type="library" name="Maven: com.google.guava:guava:20.0" level="project" />
+    <orderEntry type="library" name="Maven: com.github.ben-manes.caffeine:caffeine:2.5.3" level="project" />
+    <orderEntry type="library" name="Maven: io.dropwizard.metrics:metrics-core:3.2.3" level="project" />
     <orderEntry type="library" name="Maven: javax.validation:validation-api:2.0.0.CR3" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: org.codehaus.jackson:jackson-mapper-asl:1.9.13" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: com.anthemengineering.mojo:infer-maven-plugin:0.1.0" level="project" />
@@ -113,7 +114,6 @@
     <orderEntry type="library" scope="TEST" name="Maven: org.fusesource:sigar:1.6.4" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: org.eclipse.jdt.core.compiler:ecj:4.4.2" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: org.caffinitas.ohc:ohc-core:0.4.4" level="project" />
-    <orderEntry type="library" scope="TEST" name="Maven: com.github.ben-manes.caffeine:caffeine:2.2.6" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: org.jctools:jctools-core:1.2.1" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: commons-io:commons-io:2.5" level="project" />
     <orderEntry type="library" scope="TEST" name="Maven: junit:junit:4.12" level="project" />

pom.xml

@@ -145,6 +145,21 @@
             <version>20.0</version>
         </dependency>
 
+        <!-- Caching -->
+        <dependency>
+            <groupId>com.github.ben-manes.caffeine</groupId>
+            <artifactId>caffeine</artifactId>
+            <version>2.5.3</version>
+        </dependency>
+
+        <!-- Metrics -->
+        <!-- https://mvnrepository.com/artifact/io.dropwizard.metrics/metrics-core -->
+        <dependency>
+            <groupId>io.dropwizard.metrics</groupId>
+            <artifactId>metrics-core</artifactId>
+            <version>3.2.3</version>
+        </dependency>
+
         <!-- Validation -->
         <dependency>
             <groupId>javax.validation</groupId>

src/main/java/net/helenus/core/AbstractSessionOperations.java

@@ -129,8 +129,7 @@ public abstract class AbstractSessionOperations {
 		}
 	}
 
-	public void cache(String key, Object value) {
-	}
+	public abstract void cache(String key, Object value);
 
 	RuntimeException translateException(RuntimeException e) {
 

src/main/java/net/helenus/core/HelenusSession.java

@@ -15,20 +15,13 @@
  */
 package net.helenus.core;
 
-import java.io.Closeable;
-import java.io.PrintStream;
-import java.util.Map;
-import java.util.Objects;
-import java.util.concurrent.Executor;
-import java.util.concurrent.TimeUnit;
-import java.util.function.Function;
-
+import com.codahale.metrics.MetricRegistry;
 import com.datastax.driver.core.*;
-import com.google.common.cache.Cache;
-import com.google.common.cache.CacheBuilder;
-
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
 import net.helenus.core.operation.*;
 import net.helenus.core.reflect.HelenusPropertyNode;
+import net.helenus.mapping.ColumnType;
 import net.helenus.mapping.HelenusEntity;
 import net.helenus.mapping.MappingUtil;
 import net.helenus.mapping.value.*;
@@ -37,10 +30,15 @@ import net.helenus.support.Fun.Tuple1;
 import net.helenus.support.Fun.Tuple2;
 import net.helenus.support.Fun.Tuple6;
 
-public final class HelenusSession extends AbstractSessionOperations implements Closeable {
+import java.io.Closeable;
+import java.io.PrintStream;
+import java.util.Map;
+import java.util.Objects;
+import java.util.concurrent.Executor;
+import java.util.concurrent.TimeUnit;
+import java.util.function.Function;
 
-	private final int MAX_CACHE_SIZE = 10000;
-	private final int MAX_CACHE_EXPIRE_SECONDS = 600;
+public final class HelenusSession extends AbstractSessionOperations implements Closeable {
 
 	private final Session session;
 	private final CodecRegistry registry;
@@ -54,12 +52,13 @@ public final class HelenusSession extends AbstractSessionOperations implements C
 	private final RowColumnValueProvider valueProvider;
 	private final StatementColumnValuePreparer valuePreparer;
 	private final Metadata metadata;
+	private final MetricRegistry metricRegistry;
     private final Cache<String, Object> sessionCache;
 	private UnitOfWork currentUnitOfWork;
 
 	HelenusSession(Session session, String usingKeyspace, CodecRegistry registry, boolean showCql,
             PrintStream printStream, SessionRepositoryBuilder sessionRepositoryBuilder, Executor executor,
-            boolean dropSchemaOnClose) {
+            boolean dropSchemaOnClose, MetricRegistry metricRegistry) {
 		this.session = session;
 		this.registry = registry == null ? CodecRegistry.DEFAULT_INSTANCE : registry;
 		this.usingKeyspace = Objects.requireNonNull(usingKeyspace,
@@ -73,9 +72,16 @@ public final class HelenusSession extends AbstractSessionOperations implements C
 		this.valueProvider = new RowColumnValueProvider(this.sessionRepository);
 		this.valuePreparer = new StatementColumnValuePreparer(this.sessionRepository);
 		this.metadata = session.getCluster().getMetadata();
-		this.sessionCache = CacheBuilder.newBuilder().maximumSize(MAX_CACHE_SIZE)
-				.expireAfterAccess(MAX_CACHE_EXPIRE_SECONDS, TimeUnit.SECONDS).recordStats().build();
         this.currentUnitOfWork = null;
+
+        this.metricRegistry = metricRegistry;
+        Caffeine<Object, Object> cacheBuilder = Caffeine.newBuilder()
+                .expireAfterWrite(5, TimeUnit.MINUTES)
+                .maximumSize(10_000);
+        if (this.metricRegistry != null) {
+            cacheBuilder.recordStats(() -> new MetricsStatsCounter(metricRegistry, "helenus-session-cache"));
+        }
+        sessionCache = cacheBuilder.build();
 	}
 
 	@Override
@@ -160,7 +166,11 @@ public final class HelenusSession extends AbstractSessionOperations implements C
 	}
 
 	public void cache(String key, Object value) {
-		sessionCache.put(key, value); // ttl
+        sessionCache.put(key, value);
+	}
+
+	public Object fetch(String key) {
+        return sessionCache.getIfPresent(key);
     }
 
 	public <E> SelectOperation<E> select(Class<E> entityClass) {
@@ -172,7 +182,21 @@ public final class HelenusSession extends AbstractSessionOperations implements C
 		return new SelectOperation<E>(this, entity, (r) -> {
 
 			Map<String, Object> map = new ValueProviderMap(r, valueProvider, entity);
-			return (E) Helenus.map(entityClass, map);
+			E pojo = (E) Helenus.map(entityClass, map);
+			if (entity.isCacheable()) {
+			    StringBuilder cacheKey = new StringBuilder();
+                entity.getOrderedProperties().stream().forEach(property -> {
+                    ColumnType ct = property.getColumnType();
+                    switch (ct) {
+                    case PARTITION_KEY:
+                    case CLUSTERING_COLUMN:
+                        cacheKey.append(map.get(property.getPropertyName()).toString());
+                        break;
+                    }
+                });
+			    cache(cacheKey.toString(), pojo);
+            }
+			return pojo;
 
 		});
 	}

src/main/java/net/helenus/core/MetricsStatsCounter.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2016 Ben Manes. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package net.helenus.core;
+
+import static java.util.Objects.requireNonNull;
+
+import java.util.concurrent.TimeUnit;
+
+import com.codahale.metrics.Meter;
+import com.codahale.metrics.MetricRegistry;
+import com.codahale.metrics.Timer;
+import com.github.benmanes.caffeine.cache.stats.CacheStats;
+import com.github.benmanes.caffeine.cache.stats.StatsCounter;
+
+/**
+ * A {@link StatsCounter} instrumented with Dropwizard Metrics.
+ *
+ * @author ben.manes@gmail.com (Ben Manes)
+ */
+public final class MetricsStatsCounter implements StatsCounter {
+    private final Meter hitCount;
+    private final Meter missCount;
+    private final Meter loadSuccessCount;
+    private final Meter loadFailureCount;
+    private final Timer totalLoadTime;
+    private final Meter evictionCount;
+    private final Meter evictionWeight;
+
+    /**
+     * Constructs an instance for use by a single cache.
+     *
+     * @param registry the registry of metric instances
+     * @param metricsPrefix the prefix name for the metrics
+     */
+    public MetricsStatsCounter(MetricRegistry registry, String metricsPrefix) {
+        requireNonNull(metricsPrefix);
+        hitCount = registry.meter(metricsPrefix + ".hits");
+        missCount = registry.meter(metricsPrefix + ".misses");
+        totalLoadTime = registry.timer(metricsPrefix + ".loads");
+        loadSuccessCount = registry.meter(metricsPrefix + ".loads-success");
+        loadFailureCount = registry.meter(metricsPrefix + ".loads-failure");
+        evictionCount = registry.meter(metricsPrefix + ".evictions");
+        evictionWeight = registry.meter(metricsPrefix + ".evictions-weight");
+    }
+
+    @Override
+    public void recordHits(int count) {
+        hitCount.mark(count);
+    }
+
+    @Override
+    public void recordMisses(int count) {
+        missCount.mark(count);
+    }
+
+    @Override
+    public void recordLoadSuccess(long loadTime) {
+        loadSuccessCount.mark();
+        totalLoadTime.update(loadTime, TimeUnit.NANOSECONDS);
+    }
+
+    @Override
+    public void recordLoadFailure(long loadTime) {
+        loadFailureCount.mark();
+        totalLoadTime.update(loadTime, TimeUnit.NANOSECONDS);
+    }
+
+    @Override
+    public void recordEviction() {
+        // This method is scheduled for removal in version 3.0 in favor of recordEviction(weight)
+        recordEviction(1);
+    }
+
+    @Override
+    public void recordEviction(int weight) {
+        evictionCount.mark();
+        evictionWeight.mark(weight);
+    }
+
+    @Override
+    public CacheStats snapshot() {
+        return new CacheStats(
+                hitCount.getCount(),
+                missCount.getCount(),
+                loadSuccessCount.getCount(),
+                loadFailureCount.getCount(),
+                totalLoadTime.getCount(),
+                evictionCount.getCount(),
+                evictionWeight.getCount());
+    }
+
+    @Override
+    public String toString() {
+        return snapshot().toString();
+    }
+}

src/main/java/net/helenus/core/SessionInitializer.java

@@ -15,19 +15,9 @@
  */
 package net.helenus.core;
 
-import java.io.IOException;
-import java.io.PrintStream;
-import java.util.*;
-import java.util.concurrent.Executor;
-import java.util.concurrent.Executors;
-import java.util.function.Consumer;
-import java.util.stream.Collector;
-import java.util.stream.Collectors;
-import java.util.stream.Stream;
-
+import com.codahale.metrics.MetricRegistry;
 import com.datastax.driver.core.*;
 import com.google.common.util.concurrent.MoreExecutors;
-
 import net.helenus.mapping.HelenusEntity;
 import net.helenus.mapping.HelenusEntityType;
 import net.helenus.mapping.value.ColumnValuePreparer;
@@ -35,10 +25,18 @@ import net.helenus.mapping.value.ColumnValueProvider;
 import net.helenus.support.HelenusException;
 import net.helenus.support.PackageUtil;
 
+import java.io.IOException;
+import java.io.PrintStream;
+import java.util.*;
+import java.util.concurrent.Executor;
+import java.util.concurrent.Executors;
+import java.util.function.Consumer;
+
 public final class SessionInitializer extends AbstractSessionOperations {
 
 	private final Session session;
 	private CodecRegistry registry;
+	private MetricRegistry metricRegistry;
 	private String usingKeyspace;
 	private boolean showCql = false;
 	private PrintStream printStream = System.out;
@@ -60,6 +58,9 @@ public final class SessionInitializer extends AbstractSessionOperations {
 		this.sessionRepository = new SessionRepositoryBuilder(session);
 	}
 
+	@Override
+	public void cache(String key, Object value) { }
+
 	@Override
 	public Session currentSession() {
 		return session;
@@ -116,6 +117,12 @@ public final class SessionInitializer extends AbstractSessionOperations {
 		return this;
 	}
 
+	public SessionInitializer withMetricsRegistry(MetricRegistry metricRegistry) {
+        Objects.requireNonNull(metricRegistry, "empty registry");
+        this.metricRegistry = metricRegistry;
+        return this;
+    }
+
 	public SessionInitializer withCachingExecutor() {
 		this.executor = Executors.newCachedThreadPool();
 		return this;
@@ -206,7 +213,7 @@ public final class SessionInitializer extends AbstractSessionOperations {
 	public synchronized HelenusSession get() {
 		initialize();
 		return new HelenusSession(session, usingKeyspace, registry, showCql, printStream, sessionRepository, executor,
-				autoDdl == AutoDdl.CREATE_DROP);
+				autoDdl == AutoDdl.CREATE_DROP, metricRegistry);
 	}
 
 	private void initialize() {

src/main/java/net/helenus/core/operation/AbstractFilterStreamOperation.java

@@ -21,8 +21,7 @@ import java.util.List;
 import net.helenus.core.*;
 
 public abstract class AbstractFilterStreamOperation<E, O extends AbstractFilterStreamOperation<E, O>>
-		extends
-			AbstractStreamOperation<E, O> {
+		extends	AbstractStreamOperation<E, O> {
 
 	protected List<Filter<?>> filters = null;
 	protected List<Filter<?>> ifFilters = null;

src/main/java/net/helenus/core/operation/AbstractOperation.java

@@ -74,6 +74,7 @@ public abstract class AbstractOperation<E, O extends AbstractOperation<E, O>> ex
 			sessionOps.cache(getCacheKey(), result);
 		}
 		return result;
+
 	}
 
 	public ListenableFuture<E> async() {

src/main/java/net/helenus/core/operation/AbstractStreamOperation.java

@@ -21,6 +21,7 @@ import com.datastax.driver.core.PreparedStatement;
 import com.datastax.driver.core.ResultSet;
 import com.datastax.driver.core.ResultSetFuture;
 import com.google.common.base.Function;
+import com.google.common.util.concurrent.FutureCallback;
 import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 
@@ -64,10 +65,18 @@ public abstract class AbstractStreamOperation<E, O extends AbstractStreamOperati
 	}
 
 	public Stream<E> sync() {
+	    ListenableFuture<Stream<E>> future = async();
+        Futures.addCallback(future, new FutureCallback<String>() {
+            @Override
+            public void onSuccess(String contents) {
+                //...process web site contents
+            }
 
-		ResultSet resultSet = sessionOps.executeAsync(options(buildStatement()), showValues).getUninterruptibly();
-
-		return transform(resultSet);
+            @Override
+            public void onFailure(Throwable throwable) {
+                log.error("Exception in task", throwable);
+            }
+        });
 	}
 
 	public ListenableFuture<Stream<E>> async() {

src/main/java/net/helenus/core/operation/SelectOperation.java

@@ -221,6 +221,14 @@ public final class SelectOperation<E> extends AbstractFilterStreamOperation<E, S
 		return select;
 	}
 
+	@Override
+	public Optional<E> sync() {
+	    if (true) {
+        } else {
+            return super.sync();
+        }
+	}
+
 		@SuppressWarnings("unchecked")
 	@Override
 	public Stream<E> transform(ResultSet resultSet) {

src/test/java/net/helenus/test/integration/core/cached/SessionCacheTest.java

@@ -0,0 +1,64 @@
+package net.helenus.test.integration.core.cached;
+
+import com.datastax.driver.core.ResultSet;
+import com.datastax.driver.core.utils.UUIDs;
+import net.helenus.core.Helenus;
+import net.helenus.core.HelenusSession;
+import net.helenus.core.operation.PreparedOperation;
+import net.helenus.test.integration.build.AbstractEmbeddedCassandraTest;
+import net.helenus.test.integration.core.simple.User;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.*;
+
+import static net.helenus.core.Query.eq;
+import static net.helenus.core.Query.marker;
+
+public class SessionCacheTest extends AbstractEmbeddedCassandraTest {
+
+    static HelenusSession session;
+    static Tree tree;
+
+    static Random rnd = new Random();
+    static Set<UUID> keys = new HashSet<UUID>();
+
+    @BeforeClass
+    public static void beforeTest() {
+        session = Helenus.init(getSession()).showCql().add(Tree.class).autoCreateDrop().showCql().get();
+        tree = Helenus.dsl(Tree.class, session.getMetadata());
+
+        PreparedOperation<ResultSet> insertOp =
+                session.insert()
+                        .value(tree::id, marker())
+                        .value(tree::name, marker())
+                        .value(tree::age, marker())
+                        .value(tree::height, marker())
+                        .prepare();
+
+        for (int i = 0; i < 10; i++) {
+            UUID key = UUIDs.random();
+            keys.add(key);
+            insertOp.bind(key,
+                    UUIDs.random().toString(),
+                    rnd.nextInt(1000),
+                    rnd.nextInt(5000))
+                    .sync();
+        }
+        Assert.assertEquals(session.count(tree).sync().intValue(), 10);
+    }
+
+    @Test
+    public void cacheThingsTest() throws Exception {
+        keys.forEach(key -> {
+            Optional<Tree> aTree = session.select(Tree.class)
+                    .where(tree::id, eq(key))
+                    .single()
+                    .sync();
+            Assert.assertTrue(aTree.isPresent());
+            Assert.assertEquals(session.fetch(key.toString()), aTree.get());
+        });
+    }
+
+}

src/test/java/net/helenus/test/integration/core/cached/Tree.java

@@ -0,0 +1,23 @@
+package net.helenus.test.integration.core.cached;
+
+import net.helenus.core.annotation.Cacheable;
+import net.helenus.mapping.annotation.Column;
+import net.helenus.mapping.annotation.PartitionKey;
+import net.helenus.mapping.annotation.Table;
+
+import java.util.UUID;
+
+@Table
+@Cacheable
+public interface Tree {
+
+    @PartitionKey
+    UUID id();
+
+    String name();
+
+    Integer age();
+
+    Integer height();
+
+}