package org.apereo.cas.monitor;
import net.sf.ehcache.Cache;
import net.sf.ehcache.config.CacheConfiguration;
import net.sf.ehcache.statistics.StatisticsGateway;
import org.apache.commons.lang3.StringUtils;
import java.util.Formatter;
/**
* Ehcache statistics wrapper.
*
* @author Marvin S. Addison
* @since 3.5.1
*/
public class EhCacheStatistics implements CacheStatistics {
private static final double TOTAL_NUMBER_BYTES_IN_ONE_MEGABYTE = 1048510.0;
private static final int PERCENTAGE_VALUE = 100;
private Cache cache;
// Flag to determine whether size units are in bytes or simple object counts
private boolean useBytes;
private long diskSize;
private long heapSize;
// Off heap size is always in units of bytes
private long offHeapSize;
/**
* Creates a new instance that delegates statistics inquiries to the given {@link Cache} instance.
*
* @param cache Cache instance for which to gather statistics.
*/
public EhCacheStatistics(final Cache cache) {
this.cache = cache;
if (cache.getCacheConfiguration().getMaxBytesLocalDisk() > 0) {
this.useBytes = true;
}
}
/**
* Gets the size of heap consumed by items stored in the cache.
*
* @return Memory size.
*/
@Override
public long getSize() {
final StatisticsGateway statistics = this.cache.getStatistics();
// Store component sizes on each call to avoid recalculating
// sizes in other methods that need them
if (this.useBytes) {
this.diskSize = statistics.getLocalDiskSizeInBytes();
this.heapSize = statistics.getLocalHeapSizeInBytes();
} else {
this.diskSize = this.cache.getDiskStoreSize();
this.heapSize = this.cache.getMemoryStoreSize();
}
this.offHeapSize = statistics.getLocalOffHeapSizeInBytes();
return this.heapSize;
}
/**
* Gets the heap memory capacity of the cache.
*
* @return Heap memory capacity.
*/
@Override
public long getCapacity() {
final CacheConfiguration config = this.cache.getCacheConfiguration();
if (this.useBytes) {
return config.getMaxBytesLocalDisk();
}
return config.getMaxElementsOnDisk();
}
@Override
public long getEvictions() {
return this.cache.getStatistics().cacheEvictedCount();
}
@Override
public int getPercentFree() {
final long capacity = getCapacity();
if (capacity == 0) {
return 0;
}
return (int) ((capacity - getSize()) * PERCENTAGE_VALUE / capacity);
}
@Override
public String getName() {
return this.cache.getName();
}
@Override
public void toString(final StringBuilder builder) {
final String name = this.getName();
if (StringUtils.isNotBlank(name)) {
builder.append(name).append(':');
}
final int free = getPercentFree();
try (Formatter formatter = new Formatter(builder)) {
if (this.useBytes) {
formatter.format("%.2f", this.heapSize / TOTAL_NUMBER_BYTES_IN_ONE_MEGABYTE);
builder.append("MB heap, ");
formatter.format("%.2f", this.diskSize / TOTAL_NUMBER_BYTES_IN_ONE_MEGABYTE);
builder.append("MB disk, ");
} else {
builder.append(this.heapSize).append(" items in heap, ");
builder.append(this.diskSize).append(" items on disk, ");
}
formatter.format("%.2f", this.offHeapSize / TOTAL_NUMBER_BYTES_IN_ONE_MEGABYTE);
builder.append("MB off-heap, ");
builder.append(free).append("% free, ");
builder.append(getEvictions()).append(" evictions");
}
}
}