001/* 002 * HA-JDBC: High-Availability JDBC 003 * Copyright (C) 2012 Paul Ferraro 004 * 005 * This program is free software: you can redistribute it and/or modify 006 * it under the terms of the GNU Lesser General Public License as published by 007 * the Free Software Foundation, either version 3 of the License, or 008 * (at your option) any later version. 009 * 010 * This program is distributed in the hope that it will be useful, 011 * but WITHOUT ANY WARRANTY; without even the implied warranty of 012 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 013 * GNU Lesser General Public License for more details. 014 * 015 * You should have received a copy of the GNU Lesser General Public License 016 * along with this program. If not, see <http://www.gnu.org/licenses/>. 017 */ 018package net.sf.hajdbc.cache.eager; 019 020import java.sql.Connection; 021import java.sql.DatabaseMetaData; 022import java.sql.SQLException; 023import java.util.Map; 024import java.util.TreeMap; 025 026import net.sf.hajdbc.Database; 027import net.sf.hajdbc.DatabaseCluster; 028import net.sf.hajdbc.DatabaseProperties; 029import net.sf.hajdbc.cache.DatabaseMetaDataCache; 030import net.sf.hajdbc.dialect.Dialect; 031import net.sf.hajdbc.util.Resources; 032 033/** 034 * Per-database {@link DatabaseMetaDataCache} implementation that populates itself eagerly. 035 * @author Paul Ferraro 036 */ 037public class EagerDatabaseMetaDataCache<Z, D extends Database<Z>> implements DatabaseMetaDataCache<Z, D> 038{ 039 private final Map<D, DatabaseProperties> map = new TreeMap<D, DatabaseProperties>(); 040 private final DatabaseCluster<Z, D> cluster; 041 042 public EagerDatabaseMetaDataCache(DatabaseCluster<Z, D> cluster) 043 { 044 this.cluster = cluster; 045 } 046 047 /** 048 * {@inheritDoc} 049 * @see net.sf.hajdbc.cache.DatabaseMetaDataCache#flush() 050 */ 051 @Override 052 public void flush() throws SQLException 053 { 054 Map<D, DatabaseProperties> map = new TreeMap<D, DatabaseProperties>(); 055 056 for (D database: this.cluster.getBalancer()) 057 { 058 Connection connection = database.connect(database.getConnectionSource(), database.decodePassword(this.cluster.getDecoder())); 059 060 try 061 { 062 map.put(database, this.createDatabaseProperties(connection)); 063 } 064 finally 065 { 066 Resources.close(connection); 067 } 068 } 069 070 synchronized (this.map) 071 { 072 this.map.clear(); 073 this.map.putAll(map); 074 } 075 } 076 077 /** 078 * {@inheritDoc} 079 * @see net.sf.hajdbc.cache.DatabaseMetaDataCache#getDatabaseProperties(net.sf.hajdbc.Database, java.sql.Connection) 080 */ 081 @Override 082 public DatabaseProperties getDatabaseProperties(D database, Connection connection) throws SQLException 083 { 084 synchronized (this.map) 085 { 086 DatabaseProperties properties = this.map.get(database); 087 088 if (properties == null) 089 { 090 properties = this.createDatabaseProperties(connection); 091 092 this.map.put(database, properties); 093 } 094 095 return properties; 096 } 097 } 098 099 private DatabaseProperties createDatabaseProperties(Connection connection) throws SQLException 100 { 101 DatabaseMetaData metaData = connection.getMetaData(); 102 Dialect dialect = this.cluster.getDialect(); 103 return new EagerDatabaseProperties(metaData, dialect); 104 } 105}