1 /***
2 * Copyright 2003-2010 Terracotta, Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package net.sf.ehcache.store;
18
19 import net.sf.ehcache.Ehcache;
20 import net.sf.ehcache.bootstrap.BootstrapCacheLoader;
21
22 /***
23 * Abstract class for BootstrapCacheLoader implementers that should alter their load behavior (probably stop loading)
24 * whenever the cache being bootstrapped has reached its in-memory limit (off- or on-heap)
25 *
26 * @author Alex Snaps
27 */
28 public abstract class MemoryLimitedCacheLoader implements BootstrapCacheLoader, Cloneable {
29
30 /***
31 * Checks whether the cache has reached the limit configured for in-memory storage
32 *
33 * @param cache The cache being loaded and to be checked for limit being reached
34 * @param loadedElements amounts of elements loaded so far
35 * @return true if on-heap or off-heap limit has been reached, false otherwise
36 */
37 protected boolean isInMemoryLimitReached(final Ehcache cache, final int loadedElements) {
38
39 long maxBytesInMem;
40 long maxElementsInMem;
41 final boolean overflowToOffHeap = cache.getCacheConfiguration().isOverflowToOffHeap();
42 if (overflowToOffHeap) {
43 maxBytesInMem = cache.getCacheConfiguration().getMaxBytesLocalHeap();
44 maxElementsInMem = cache.getCacheConfiguration().getMaxEntriesLocalHeap() == 0
45 ? Integer.MAX_VALUE : cache.getCacheConfiguration().getMaxEntriesLocalHeap();
46 } else {
47 maxBytesInMem = cache.getCacheConfiguration().getMaxBytesLocalOffHeap();
48 maxElementsInMem = cache.getCacheConfiguration().getMaxEntriesLocalHeap() == 0
49 ? Integer.MAX_VALUE : cache.getCacheConfiguration().getMaxEntriesLocalHeap();
50 }
51
52 if (maxBytesInMem != 0) {
53 final long inMemorySizeInBytes = overflowToOffHeap ? cache.calculateOffHeapSize() : cache.calculateInMemorySize();
54 final long avgSize = inMemorySizeInBytes / (overflowToOffHeap ? cache.getOffHeapStoreSize() : cache.getMemoryStoreSize());
55 return inMemorySizeInBytes + (avgSize * 2) >= maxBytesInMem;
56 } else {
57 return loadedElements >= maxElementsInMem;
58 }
59 }
60
61 /***
62 * {@inheritDoc}
63 */
64 @Override
65 public Object clone() throws CloneNotSupportedException {
66 return super.clone();
67 }
68 }