简单的Coherence 实现数据库读写缓存
自定义数据缓存DAO类，必须实现com.tangosol.net.cache.CacheStore接口或者com.tangosol.net.cache.CacheLoader 接口，由于 com.tangosol.net.cache.AbstractCacheStore 继承了com.tangosol.net.cache.AbstractCacheLoader 实现了 com.tangosol.net.cache.CacheStore类。
实现类如下：
package com.etrip.app;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import com.tangosol.net.cache.AbstractCacheStore;
/**
* 自定义数据缓存DAO类，必须实现com.tangosol.net.cache.CacheStore接口或者
* com.tangosol.net.cache.CacheLoader 接口，由于 com.tangosol.net.cache.AbstractCacheStore
* 继承了com.tangosol.net.cache.AbstractCacheLoader 实现了
* com.tangosol.net.cache.CacheStore类。
* @Title: TODO
* @Description: 实现TODO
* @Copyright:Copyright (c) 2011
* @Company:
* @Date:2013-1-4
* @author
* @version 1.0
*/
public class DBCacheStore extends AbstractCacheStore {
public DBCacheStore(String sTableName) {
m_sTableName = sTableName;
configureConnection();
}
protected void configureConnection() {
try {
Class.forName(DB_DRIVER);
m_con = DriverManager.getConnection(DB_URL, DB_USERNAME,
DB_PASSWORD);
m_con.setAutoCommit(true);
} catch (Exception e) {
throw ensureRuntimeException(e, "Connection failed");
}
}
public String getTableName() {
return m_sTableName;
}
public Connection getConnection() {
return m_con;
}
public Object load(Object oKey) {
Object oValue = null;
Connection con = getConnection();
String sSQL = "SELECT id, value FROM " + getTableName()
+ " WHERE id = ?";
try {
PreparedStatement stmt = con.prepareStatement(sSQL);
stmt.setString(1, String.valueOf(oKey));
ResultSet rslt = stmt.executeQuery();
if (rslt.next()) {
oValue = rslt.getString(2);
if (rslt.next()) {
throw new SQLException("Not a unique key: " + oKey);
}
}
stmt.close();
} catch (SQLException e) {
throw ensureRuntimeException(e, "Load failed: key=" + oKey);
}
return oValue;
}
public void store(Object oKey, Object oValue) {
Connection con = getConnection();
String sTable = getTableName();
String sSQL;
if (load(oKey) != null) {
sSQL = "UPDATE " + sTable + " SET value = ? where id = ?";
} else {
sSQL = "INSERT INTO " + sTable + " (value, id) VALUES (?,?)";
}
try {
PreparedStatement stmt = con.prepareStatement(sSQL);
int i = 0;
stmt.setString(++i, String.valueOf(oValue));
stmt.setString(++i, String.valueOf(oKey));
stmt.executeUpdate();
stmt.close();
} catch (SQLException e) {
throw ensureRuntimeException(e, "Store failed: key=" + oKey);
}
}
public void erase(Object oKey) {
Connection con = getConnection();
String sSQL = "DELETE FROM " + getTableName() + " WHERE id=?";
try {
PreparedStatement stmt = con.prepareStatement(sSQL);
stmt.setString(1, String.valueOf(oKey));
stmt.executeUpdate();
stmt.close();
} catch (SQLException e) {
throw ensureRuntimeException(e, "Erase failed: key=" + oKey);
}
}
public void eraseAll(Collection colKeys) {
super.eraseAll(colKeys);
}
public Map loadAll(Collection colKeys) {
return super.loadAll(colKeys);
}
public void storeAll(Map mapEntries) {
super.storeAll(mapEntries);
}
public Iterator keys() {
Connection con = getConnection();
String sSQL = "SELECT id FROM " + getTableName();
List list = new LinkedList();
try {
PreparedStatement stmt = con.prepareStatement(sSQL);
ResultSet rslt = stmt.executeQuery();
while (rslt.next()) {
Object oKey = rslt.getString(1);
list.add(oKey);
}
stmt.close();
} catch (SQLException e) {
throw ensureRuntimeException(e, "Iterator failed");
}
return list.iterator();
}
protected Connection m_con;
protected String m_sTableName;
private static final String DB_DRIVER = "com.mysql.jdbc.Driver";
private static final String DB_URL = "jdbc:mysql://localhost:3306/biz?user=root&password=123456&useUnicode=true&characterEncoding=utf8&autoReconnect=true&failOverReadOnly=false";
private static final String DB_USERNAME = "root";
private static final String DB_PASSWORD = "123456";
}coherence的配置文件：
<?xml version="1.0"?>
<cache-config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://xmlns.oracle.com/coherence/coherence-cache-config"
xsi:schemaLocation="http://xmlns.oracle.com/coherence/coherence-cache-config coherence-cache-config.xsd">
<caching-scheme-mapping>
<!--
Caches with names that start with 'DBBacked' will be created
as distributed-db-backed.
-->
<cache-mapping>
<cache-name>DBBacked*</cache-name>
<scheme-name>distributed-db-backed</scheme-name>
</cache-mapping>
<cache-mapping>
<cache-name>VirtualCache</cache-name>
<scheme-name>distributed-db-backed</scheme-name>
</cache-mapping>
</caching-scheme-mapping>
<caching-schemes>
<!--
DB Backed Distributed caching scheme.
-->
<distributed-scheme>
<scheme-name>distributed-db-backed</scheme-name>
<service-name>DistributedCache</service-name>
<backing-map-scheme>
<read-write-backing-map-scheme>
<internal-cache-scheme>
<class-scheme>
<class-name>com.tangosol.util.ObservableHashMap</class-name>
</class-scheme>
</internal-cache-scheme>
<cachestore-scheme>
<class-scheme>
<class-name>com.etrip.app.DBCacheStore</class-name>
<init-params>
<init-param>
<param-type>java.lang.String</param-type>
<param-value>CATALOG</param-value>
</init-param>
</init-params>
</class-scheme>
</cachestore-scheme>
<read-only>false</read-only>
<!--
To make this a write-through cache just change the value below to 0 (zero)
-->
<write-delay-seconds>0</write-delay-seconds>
</read-write-backing-map-scheme>
</backing-map-scheme>
<autostart>true</autostart>
</distributed-scheme>
</caching-schemes>
</cache-config>coherence的JVM参数配置如下：
-Dtangosol.coherence.cacheconfig=D:/jee-workspace/CoherenceApp/resources/cache-db-config.xml
测试代码：
package com.etrip.app;
import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;
import com.tangosol.net.cache.ContinuousQueryCache;
import com.tangosol.util.Filter;
import com.tangosol.util.extractor.IdentityExtractor;
import com.tangosol.util.filter.LikeFilter;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
/**
*
* @Title: TODO
* @Description: 实现TODO
* @Copyright:Copyright (c) 2011
* @Company:
* @Date:2013-1-5
* @author
* @version 1.0
*/
public class DatabaseCache {
NamedCache cache;
public DatabaseCache() {
}
public void createCache() {
cache = CacheFactory.getCache("DBBackedCache");
}
public void retrieveEntry() {
System.out.println((String) cache.get("catalog1"));
}
public void eraseEntry() {
cache.remove(new String("catalog3"));
}
public void queryCache() {
Filter filter = new LikeFilter(IdentityExtractor.INSTANCE, "Tuning%",
'\\', true);
HashSet hashSet = new HashSet();
hashSet.add(new String("catalog1"));
hashSet.add(new String("catalog2"));
hashSet.add(new String("catalog3"));
Map map = cache.getAll(hashSet);
ContinuousQueryCache queryCache = new ContinuousQueryCache(cache,
filter);
Set results = queryCache.entrySet(filter);
/* Set results = cache.entrySet(filter); */
if (results.isEmpty())
System.out.println("Result Set Empty");
for (Iterator i = results.iterator(); i.hasNext();) {
Map.Entry e = (Map.Entry) i.next();
System.out.println("Catalog ID: " + e.getKey() + ", Title: "
+ e.getValue());
}
}
public static void main(String[] args) {
DatabaseCache databaseCache = new DatabaseCache();
//创建相关的缓存
databaseCache.createCache();
//查询缓存的数据
databaseCache.queryCache();
//获取缓存的对象
databaseCache.retrieveEntry();
}
}结果：
2013-01-05 17:23:59.268/0.362 Oracle Coherence 3.7.1.1 <Info> (thread=main, member=n/a): Loaded operational configuration from "jar:file:/D:/app/Oracle/Middleware/coherence_3.7/lib/coherence.jar!/tangosol-coherence.xml"
2013-01-0517:23:59.321/0.415OracleCoherence3.7.1.1<Info>(thread=main,member=n/a):Loadedoperationaloverridesfrom"jar:file:/D:/app/Oracle/Middleware/coherence_3.7/lib/coherence.jar!/tangosol-coherence-override-dev.xml"
2013-01-0517:23:59.322/0.416OracleCoherence3.7.1.1<D5>(thread=main,member=n/a):Optionalconfigurationoverride"/tangosol-coherence-override.xml"isnotspecified
2013-01-05 17:23:59.326/0.421 Oracle Coherence 3.7.1.1 <D5> (thread=main, member=n/a): Optional configuration override "/custom-mbeans.xml" is not specifiedOracle Coherence Version 3.7.1.1 Build 28901
GridEdition:Developmentmode
Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.2013-01-05 17:23:59.549/0.643 Oracle Coherence GE 3.7.1.1 <Info> (thread=main, member=n/a): Loaded cache configuration from "file:/D:/jee-workspace/CoherenceApp/resources/cache-db-config.xml"
2013-01-0517:24:00.378/1.472OracleCoherenceGE3.7.1.1<D4>(thread=main,member=n/a):TCMPboundto/172.30.101.179:8088usingSystemSocketProvider
2013-01-0517:24:03.808/4.902OracleCoherenceGE3.7.1.1<Info>(thread=Cluster,member=n/a):Createdanewcluster"cluster:0xFCDB"withMember(Id=1,Timestamp=2013-01-0517:24:00.531,Address=172.30.101.179:8088,MachineId=6892,Location=site:,machine:longgangbai-PC,process:6844,Role=EtripAppDatabaseCache,Edition=GridEdition,Mode=Development,CpuCount=4,SocketCount=4)UID=0xAC1E65B30000013C0A0625931AEC1F98
2013-01-05 17:24:03.815/4.909 Oracle Coherence GE 3.7.1.1 <Info> (thread=main, member=n/a): Started cluster Name=cluster:0xFCDBGroup{Address=224.3.7.0, Port=37000, TTL=4}
MasterMemberSet(
ThisMember=Member(Id=1,Timestamp=2013-01-0517:24:00.531,Address=172.30.101.179:8088,MachineId=6892,Location=site:,machine:longgangbai-PC,process:6844,Role=EtripAppDatabaseCache)
OldestMember=Member(Id=1,Timestamp=2013-01-0517:24:00.531,Address=172.30.101.179:8088,MachineId=6892,Location=site:,machine:longgangbai-PC,process:6844,Role=EtripAppDatabaseCache)
ActualMemberSet=MemberSet(Size=1
Member(Id=1,Timestamp=2013-01-0517:24:00.531,Address=172.30.101.179:8088,MachineId=6892,Location=site:,machine:longgangbai-PC,process:6844,Role=EtripAppDatabaseCache)
)
MemberId|ServiceVersion|ServiceJoined|MemberState
1|3.7.1|2013-01-0517:24:03.808|JOINED
RecycleMillis=1200000
RecycleSet=MemberSet(Size=0
)
)TcpRing{Connections=[]}IpMonitor{AddressListSize=0}
2013-01-05 17:24:03.861/4.955 Oracle Coherence GE 3.7.1.1 <D5> (thread=Invocation:Management, member=1): Service Management joined the cluster with senior service member 1
2013-01-0517:24:04.140/5.234OracleCoherenceGE3.7.1.1<D5>(thread=DistributedCache,member=1):ServiceDistributedCachejoinedtheclusterwithseniorservicemember1
CatalogID:catalog1,Title:TuningUndoTablespace
CatalogID:catalog2,Title:TuningYourViewObjects
TuningUndoTablespace
2013-01-0517:24:04.611/5.705OracleCoherenceGE3.7.1.1<D4>(thread=ShutdownHook,member=1):ShutdownHook:stoppingclusternode
2013-01-0517:24:04.613/5.707OracleCoherenceGE3.7.1.1<D5>(thread=Cluster,member=n/a):ServiceClusterleftthecluster
2013-01-0517:24:04.616/5.710OracleCoherenceGE3.7.1.1<D5>(thread=DistributedCache,member=n/a):ServiceDistributedCacheleftthecluster