/*
* Copyright (C) 2012 Timo Vesalainen
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.vesalainen.parsers.sql.dsql;
import com.google.appengine.api.datastore.DatastoreService;
import com.google.appengine.api.datastore.Entity;
import com.google.appengine.api.datastore.Index;
import com.google.appengine.api.datastore.Index.IndexState;
import com.google.appengine.api.datastore.PreparedQuery;
import com.google.appengine.api.datastore.Query;
import com.google.appengine.api.datastore.Query.Filter;
import com.google.appengine.api.datastore.Query.FilterPredicate;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.TreeMap;
import org.vesalainen.parsers.sql.ColumnMetadata;
import org.vesalainen.parsers.sql.TableMetadata;
/**
* @author Timo Vesalainen
*/
public final class Statistics
{
private static final long DAY = 24*60*60*1000;
private long nextUpdate;
private DatastoreService datastore;
private final Map<String, TableMetadata> map = new TreeMap<>();
private Map<Index, IndexState> indexes;
private boolean hasNamespaces = true;
public Statistics(DatastoreService datastore)
{
this.datastore = datastore;
update();
}
public void update()
{
synchronized(map)
{
if (System.currentTimeMillis() > nextUpdate)
{
indexes = datastore.getIndexes();
map.clear();
Query q0 = new Query("__Stat_Ns_Total__");
Entity total = datastore.prepare(q0).asSingleEntity();
if (total == null)
{
hasNamespaces = false;
q0 = new Query("__Stat_Total__");
total = datastore.prepare(q0).asSingleEntity();
}
if (total != null)
{
Date timestamp = (Date) total.getProperty("timestamp");
nextUpdate = timestamp.getTime() + DAY;
String statProperty;
if (hasNamespaces)
{
statProperty = "__Stat_Ns_PropertyName_Kind__";
}
else
{
statProperty = "__Stat_PropertyName_Kind__";
}
Query q1 = new Query(statProperty);
Filter filter = new FilterPredicate("timestamp", Query.FilterOperator.EQUAL, timestamp);
q1.setFilter(filter);
PreparedQuery p1 = datastore.prepare(q1);
for (Entity prop : p1.asIterable())
{
String kind = (String) prop.getProperty("kind_name");
if (!kind.startsWith("_"))
{
String property = (String) prop.getProperty("property_name");
long count = (long) prop.getProperty("count");
long indexCount = (long) prop.getProperty("builtin_index_count");
KindEntry kindEntry = (KindEntry) map.get(kind.toUpperCase());
if (kindEntry == null)
{
kindEntry = new KindEntry(kind);
map.put(kind.toUpperCase(), kindEntry);
}
kindEntry.addProperty(property, count, indexCount > 0);
}
}
}
}
}
}
public Map<Index, IndexState> getIndexes()
{
return indexes;
}
public TableMetadata getKind(String name)
{
if (name != null)
{
return map.get(name.toUpperCase());
}
return null;
}
public ColumnMetadata getProperty(String kind, String property)
{
KindEntry kindEntry = (KindEntry) getKind(kind);
if (kindEntry != null)
{
return kindEntry.getColumnMetadata(property);
}
return null;
}
public Iterable<TableMetadata> getTables()
{
return map.values();
}
public class KindEntry implements TableMetadata, Iterable<ColumnMetadata>
{
private String name;
private long entityCount;
private Map<String,ColumnMetadata> properties = new HashMap<>();
private PropertyEntry key;
public KindEntry(String name)
{
this.name = name;
}
public void addProperty(String name, long count, boolean indexed)
{
if (!properties.containsKey(name))
{
properties.put(name.toUpperCase(), new PropertyEntry(name, count, indexed));
}
if (entityCount < count)
{
entityCount = count;
}
}
@Override
public ColumnMetadata getColumnMetadata(String name)
{
if (Entity.KEY_RESERVED_PROPERTY.equals(name))
{
if (key == null)
{
key = new PropertyEntry(name, entityCount, true, true);
}
return key;
}
return properties.get(name.toUpperCase());
}
public long getEntityCount()
{
return entityCount;
}
@Override
public String getName()
{
return name;
}
@Override
public long getCount()
{
return entityCount;
}
@Override
public Iterable<ColumnMetadata> getColumns()
{
return this;
}
@Override
public Iterator<ColumnMetadata> iterator()
{
return properties.values().iterator();
}
@Override
public String toString()
{
return name;
}
}
public class PropertyEntry implements ColumnMetadata
{
private String name;
private long count;
private boolean indexed;
private boolean unique;
public PropertyEntry(String name, long count, boolean indexed)
{
this.name = name;
this.count = count;
this.indexed = indexed;
}
public PropertyEntry(String name, long count, boolean indexed, boolean unique)
{
this.name = name;
this.count = count;
this.indexed = indexed;
this.unique = unique;
}
@Override
public long getCount()
{
return count;
}
@Override
public boolean isUnique()
{
return unique;
}
@Override
public boolean isIndexed()
{
return indexed;
}
public long getEstimatedCount()
{
if (indexed)
{
return count / 10;
}
else
{
return count;
}
}
@Override
public String getName()
{
return name;
}
@Override
public float getSelectivity()
{
throw new UnsupportedOperationException("Not supported yet.");
}
@Override
public String toString()
{
return name;
}
}
}