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Posted to commits@activemq.apache.org by cl...@apache.org on 2018/05/14 13:48:27 UTC
[3/3] activemq-artemis git commit: ARTEMIS-1783 Remove need for guava
in client
ARTEMIS-1783 Remove need for guava in client
Refactor away from Guava memorize based on Guava Supplier to using java.util.Supplier and our own memorizer code.
Project: http://git-wip-us.apache.org/repos/asf/activemq-artemis/repo
Commit: http://git-wip-us.apache.org/repos/asf/activemq-artemis/commit/19418630
Tree: http://git-wip-us.apache.org/repos/asf/activemq-artemis/tree/19418630
Diff: http://git-wip-us.apache.org/repos/asf/activemq-artemis/diff/19418630
Branch: refs/heads/master
Commit: 19418630d4f9440b7bcbee78c9aad9202cdca02a
Parents: 6904af8
Author: Michael André Pearce <mi...@me.com>
Authored: Fri May 11 07:24:35 2018 +0100
Committer: Clebert Suconic <cl...@apache.org>
Committed: Mon May 14 09:45:41 2018 -0400
----------------------------------------------------------------------
.../activemq/artemis/utils/Suppliers.java | 95 ++++++++++++++++++++
.../message/impl/CoreMessageObjectPools.java | 6 +-
2 files changed, 99 insertions(+), 2 deletions(-)
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http://git-wip-us.apache.org/repos/asf/activemq-artemis/blob/19418630/artemis-commons/src/main/java/org/apache/activemq/artemis/utils/Suppliers.java
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diff --git a/artemis-commons/src/main/java/org/apache/activemq/artemis/utils/Suppliers.java b/artemis-commons/src/main/java/org/apache/activemq/artemis/utils/Suppliers.java
new file mode 100644
index 0000000..59ccd77
--- /dev/null
+++ b/artemis-commons/src/main/java/org/apache/activemq/artemis/utils/Suppliers.java
@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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 org.apache.activemq.artemis.utils;
+
+import java.io.Serializable;
+import java.util.function.Supplier;
+
+public class Suppliers {
+
+ /**
+ * Returns a supplier which caches the instance retrieved during the first
+ * call to {@code get()} and returns that value on subsequent calls to
+ * {@code get()}. See:
+ * <a href="http://en.wikipedia.org/wiki/Memoization">memoization</a>
+ *
+ * <p>The returned supplier is thread-safe. The delegate's {@code get()}
+ * method will be invoked at most once. The supplier's serialized form does
+ * not contain the cached value, which will be recalculated when {@code get()}
+ * is called on the reserialized instance.
+ *
+ * <p>If {@code delegate} is an instance created by an earlier call to {@code
+ * memoize}, it is returned directly.
+ */
+ public static <T> Supplier<T> memoize(Supplier<T> delegate) {
+ return (delegate instanceof MemoizingSupplier)
+ ? delegate
+ : new MemoizingSupplier<T>(checkNotNull(delegate));
+ }
+
+ private static class MemoizingSupplier<T> implements Supplier<T>, Serializable {
+ final Supplier<T> delegate;
+ transient volatile boolean initialized;
+ // "value" does not need to be volatile; visibility piggy-backs
+ // on volatile read of "initialized".
+ transient T value;
+
+ MemoizingSupplier(Supplier<T> delegate) {
+ this.delegate = delegate;
+ }
+
+ @Override
+ public T get() {
+ // A 2-field variant of Double Checked Locking.
+ if (!initialized) {
+ synchronized (this) {
+ if (!initialized) {
+ T t = delegate.get();
+ value = t;
+ initialized = true;
+ return t;
+ }
+ }
+ }
+ return value;
+ }
+
+ @Override
+ public String toString() {
+ return "Suppliers.memoize(" + delegate + ")";
+ }
+
+ private static final long serialVersionUID = 0;
+ }
+
+ /**
+ * Ensures that an object reference passed as a parameter to the calling method is not null.
+ *
+ * @param reference an object reference
+ * @return the non-null reference that was validated
+ * @throws NullPointerException if {@code reference} is null
+ */
+ public static <T> T checkNotNull(T reference) {
+ if (reference == null) {
+ throw new NullPointerException();
+ }
+ return reference;
+ }
+}
http://git-wip-us.apache.org/repos/asf/activemq-artemis/blob/19418630/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/message/impl/CoreMessageObjectPools.java
----------------------------------------------------------------------
diff --git a/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/message/impl/CoreMessageObjectPools.java b/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/message/impl/CoreMessageObjectPools.java
index d4e3ed1..7ee7d0a 100644
--- a/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/message/impl/CoreMessageObjectPools.java
+++ b/artemis-core-client/src/main/java/org/apache/activemq/artemis/core/message/impl/CoreMessageObjectPools.java
@@ -16,11 +16,13 @@
*/
package org.apache.activemq.artemis.core.message.impl;
-import com.google.common.base.Supplier;
-import com.google.common.base.Suppliers;
+
import org.apache.activemq.artemis.api.core.SimpleString;
+import org.apache.activemq.artemis.utils.Suppliers;
import org.apache.activemq.artemis.utils.collections.TypedProperties;
+import java.util.function.Supplier;
+
public class CoreMessageObjectPools {
private Supplier<SimpleString.ByteBufSimpleStringPool> addressDecoderPool = Suppliers.memoize(SimpleString.ByteBufSimpleStringPool::new);