Issue #50 Implement offheap-resource provider

offheap-resource/src/main/java/org/terracotta/offheapresource/OffHeapResource.java

@@ -0,0 +1,58 @@
+/*
+ * The contents of this file are subject to the Terracotta Public 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://terracotta.org/legal/terracotta-public-license.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+ * the specific language governing rights and limitations under the License.
+ *
+ * The Covered Software is OffHeap Resource.
+ *
+ * The Initial Developer of the Covered Software is
+ * Terracotta, Inc., a Software AG company
+ */
+
+package org.terracotta.offheapresource;
+
+import java.util.concurrent.atomic.AtomicLong;
+
+public class OffHeapResource {
+
+  private final AtomicLong remaining;
+
+  OffHeapResource(long size) {
+    if (size < 0) {
+      throw new IllegalArgumentException("Resource size cannot be negative");
+    } else {
+      this.remaining = new AtomicLong(size);
+    }
+  }
+
+  public boolean allocate(long size) {
+    if (size < 0) {
+      throw new IllegalArgumentException("Allocation size cannot be negative");
+    } else {
+      for (long current = remaining.get(); current >= size; current = remaining.get()) {
+        if (remaining.compareAndSet(current, current - size)) {
+          return true;
+        }
+      }
+      return false;
+    }
+  }
+
+  public void free(long size) {
+    if (size < 0) {
+      throw new IllegalArgumentException("Freed size cannot be negative");
+    } else {
+      remaining.addAndGet(size);
+    }
+  }
+
+  public long available() {
+    return remaining.get();
+  }
+}

offheap-resource/src/main/java/org/terracotta/offheapresource/OffHeapResourceIdentifier.java

@@ -0,0 +1,56 @@
+/*
+ * The contents of this file are subject to the Terracotta Public 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://terracotta.org/legal/terracotta-public-license.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+ * the specific language governing rights and limitations under the License.
+ *
+ * The Covered Software is OffHeap Resource.
+ *
+ * The Initial Developer of the Covered Software is
+ * Terracotta, Inc., a Software AG company
+ */
+
+package org.terracotta.offheapresource;
+
+import org.terracotta.entity.ServiceConfiguration;
+
+/**
+ *
+ * @author cdennis
+ */
+public final class OffHeapResourceIdentifier implements ServiceConfiguration<OffHeapResource> {
+
+  private final String name;
+
+  public static OffHeapResourceIdentifier identifier(String name) {
+    return new OffHeapResourceIdentifier(name);
+  }
+
+  private OffHeapResourceIdentifier(String name) {
+    if (name == null) {
+      throw new NullPointerException("Name cannot be null");
+    } else {
+      this.name = name;
+    }
+  }
+
+  @Override
+  public int hashCode() {
+    return name.hashCode();
+  }
+
+  @Override
+  public boolean equals(Object obj) {
+    return (obj instanceof OffHeapResourceIdentifier) && name.equals(((OffHeapResourceIdentifier) obj).name);
+  }
+
+  @Override
+  public Class<OffHeapResource> getServiceType() {
+    return OffHeapResource.class;
+  }
+}

offheap-resource/src/main/java/org/terracotta/offheapresource/OffHeapResourcesProvider.java

@@ -1,39 +1,89 @@
 /*
- * To change this license header, choose License Headers in Project Properties.
- * To change this template file, choose Tools | Templates
- * and open the template in the editor.
+ * The contents of this file are subject to the Terracotta Public 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://terracotta.org/legal/terracotta-public-license.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+ * the specific language governing rights and limitations under the License.
+ *
+ * The Covered Software is OffHeap Resource.
+ *
+ * The Initial Developer of the Covered Software is
+ * Terracotta, Inc., a Software AG company
  */
+
 package org.terracotta.offheapresource;
 
 import java.io.IOException;
+import java.math.BigInteger;
 import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+
 import org.terracotta.entity.ServiceConfiguration;
 import org.terracotta.entity.ServiceProvider;
 import org.terracotta.entity.ServiceProviderConfiguration;
+import org.terracotta.offheapresource.config.MemoryUnit;
+import org.terracotta.offheapresource.config.ResourceType;
 
 /**
  *
  * @author cdennis
  */
 class OffHeapResourcesProvider implements ServiceProvider {
 
+  private final Map<OffHeapResourceIdentifier, OffHeapResource> resources = new HashMap<OffHeapResourceIdentifier, OffHeapResource>();
+
   @Override
-  public boolean initialize(ServiceProviderConfiguration configuration) {
-    throw new UnsupportedOperationException();
+  public synchronized boolean initialize(ServiceProviderConfiguration unknownConfig) {
+    if (unknownConfig instanceof OffHeapResourcesConfiguration) {
+      OffHeapResourcesConfiguration configuration = (OffHeapResourcesConfiguration) unknownConfig;
+      if (resources.isEmpty()) {
+        for (ResourceType r : configuration.getResources()) {
+          resources.put(OffHeapResourceIdentifier.identifier(r.getName()), new OffHeapResource(convert(r.getValue(), r.getUnit()).longValueExact()));
+        }
+        return true;
+      } else {
+        throw new IllegalStateException("Resources already initialized");
+      }
+    } else {
+      return false;
+    }
   }
 
   @Override
-  public <T> T getService(long consumerID, ServiceConfiguration<T> configuration) {
-    throw new UnsupportedOperationException();
+  public <T> T getService(long consumerID, ServiceConfiguration<T> unknownConfiguration) {
+    if (unknownConfiguration instanceof OffHeapResourceIdentifier) {
+      OffHeapResourceIdentifier identifier = (OffHeapResourceIdentifier) unknownConfiguration;
+      return (T) identifier.getServiceType().cast(resources.get(identifier));
+    } else {
+      throw new IllegalArgumentException("Unexpected configuration type " + unknownConfiguration.getClass());
+    }
   }
 
   @Override
   public Collection<Class<?>> getProvidedServiceTypes() {
-    throw new UnsupportedOperationException();
+    return Collections.<Class<?>>singleton(OffHeapResource.class);
   }
 
   @Override
-  public void close() throws IOException {
-    throw new UnsupportedOperationException();
+  public void close() {
+    resources.clear();
+  }
+
+  private static BigInteger convert(BigInteger value, MemoryUnit unit) {
+    switch (unit) {
+      case B: return value.shiftLeft(0);
+      case K_B: return value.shiftLeft(10);
+      case MB: return value.shiftLeft(20);
+      case GB: return value.shiftLeft(30);
+      case TB: return value.shiftLeft(40);
+      case PB: return value.shiftLeft(50);
+    }
+    throw new IllegalArgumentException("Unknown unit " + unit);
   }
 }

offheap-resource/src/test/java/org/terracotta/offheapresource/OffHeapResourceIdentifierTest.java

@@ -0,0 +1,53 @@
+/*
+ * The contents of this file are subject to the Terracotta Public 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://terracotta.org/legal/terracotta-public-license.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+ * the specific language governing rights and limitations under the License.
+ *
+ * The Covered Software is OffHeap Resource.
+ *
+ * The Initial Developer of the Covered Software is
+ * Terracotta, Inc., a Software AG company
+ */
+package org.terracotta.offheapresource;
+
+import static org.hamcrest.core.Is.is;
+import org.junit.Test;
+
+import static org.hamcrest.core.IsEqual.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+
+public class OffHeapResourceIdentifierTest {
+
+  @Test
+  public void testNullName() {
+    try {
+      OffHeapResourceIdentifier.identifier(null);
+      fail("Expected NullPointerException");
+    } catch (NullPointerException e) {
+      //expected
+    }
+  }
+
+  @Test
+  public void testServiceType() {
+    assertThat(OffHeapResourceIdentifier.identifier("foo").getServiceType(), equalTo(OffHeapResource.class));
+  }
+
+  @Test
+  public void testEquals() {
+    assertThat(OffHeapResourceIdentifier.identifier("foo").equals(OffHeapResourceIdentifier.identifier("foo")), is(true));
+    assertThat(OffHeapResourceIdentifier.identifier("foo").equals(OffHeapResourceIdentifier.identifier("bar")), is(false));
+  }
+
+  @Test
+  public void testHashcode() {
+    assertThat(OffHeapResourceIdentifier.identifier("foo").hashCode(), is(OffHeapResourceIdentifier.identifier("foo").hashCode()));
+  }
+}

offheap-resource/src/test/java/org/terracotta/offheapresource/OffHeapResourceTest.java

@@ -0,0 +1,91 @@
+/*
+ * The contents of this file are subject to the Terracotta Public 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://terracotta.org/legal/terracotta-public-license.
+ *
+ * Software distributed under the License is distributed on an "AS IS" basis,
+ * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License for
+ * the specific language governing rights and limitations under the License.
+ *
+ * The Covered Software is OffHeap Resource.
+ *
+ * The Initial Developer of the Covered Software is
+ * Terracotta, Inc., a Software AG company
+ */
+
+package org.terracotta.offheapresource;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+import org.junit.Test;
+
+public class OffHeapResourceTest {
+
+  @Test
+  public void testNegativeResourceSize() {
+    try {
+      new OffHeapResource(-1);
+      fail("Expected IllegalArgumentException");
+    } catch (IllegalArgumentException e) {
+      //expected;
+    }
+  }
+
+  @Test
+  public void testZeroSizeResourceIsUseless() {
+    OffHeapResource ohr = new OffHeapResource(0);
+    assertThat(ohr.allocate(1), is(false));
+    assertThat(ohr.available(), is(0L));
+  }
+
+  @Test
+  public void testAllocationReducesSize() {
+    OffHeapResource ohr = new OffHeapResource(20);
+    assertThat(ohr.available(), is(20L));
+    assertThat(ohr.allocate(10), is(true));
+    assertThat(ohr.available(), is(10L));
+  }
+
+  @Test
+  public void testNegativeAllocationFails() {
+    OffHeapResource ohr = new OffHeapResource(20);
+    try {
+      ohr.allocate(-1);
+      fail("Expected IllegalArgumentException");
+    } catch (IllegalArgumentException e) {
+      //expected
+    }
+  }
+
+  @Test
+  public void testAllocationWhenExhaustedFails() {
+    OffHeapResource ohr = new OffHeapResource(20);
+    ohr.allocate(20);
+    assertThat(ohr.allocate(1), is(false));
+    assertThat(ohr.available(), is(0L));
+  }
+
+  @Test
+  public void testFreeIncreasesSize() {
+    OffHeapResource ohr = new OffHeapResource(20);
+    ohr.allocate(20);
+    assertThat(ohr.available(), is(0L));
+    ohr.free(10);
+    assertThat(ohr.available(), is(10L));
+  }
+
+  @Test
+  public void testNegativeFreeFails() {
+    OffHeapResource ohr = new OffHeapResource(20);
+    ohr.allocate(10);
+    try {
+      ohr.free(-10);
+      fail("Expected IllegalArgumentException");
+    } catch (IllegalArgumentException e) {
+      //expected
+    }
+  }
+}