Java API for Oracle RAC Support:
Important Links:
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Implicit Connection Cache
FCF
Property fcfcache file :
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# properties required for test
username=scott
password=tiger
InitialLimit=10
MinLimit=10
MaxLimit=20
onsconfig=nodes=aulnx4-vip.au.oracle.com:6200,aulnx3-vip.au.oracle.com:6200
url=jdbc:oracle:thin:@(DESCRIPTION= \
(LOAD_BALANCE=yes) \
(ADDRESS=(PROTOCOL=TCP)(HOST=aulnx4-vip.au.oracle.com)(PORT=1521)) \
(ADDRESS=(PROTOCOL=TCP)(HOST=aulnx3-vip.au.oracle.com)(PORT=1521)) \
(CONNECT_DATA=(service_name=sales2)))
Java File
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public class FCFConnectionCacheExample
{
private OracleDataSource ods = null;
private OracleConnectionCacheManager occm = null;
private Properties cacheProperties = null;
public FCFConnectionCacheExample() throws SQLException
{
// create a cache manager
occm = OracleConnectionCacheManager.getConnectionCacheManagerInstance();
Properties props = loadProperties("fcfcache");
cacheProperties = new java.util.Properties();
cacheProperties.setProperty("InitialLimit", (String)props.get("InitialLimit"));
cacheProperties.setProperty("MinLimit", (String)props.get("MinLimit"));
cacheProperties.setProperty("MaxLimit", (String)props.get("MaxLimit"));
ods = new OracleDataSource();
ods.setUser((String)props.get("username"));
ods.setPassword((String)props.get("password"));
ods.setConnectionCachingEnabled(true);
ods.setFastConnectionFailoverEnabled(true);
ods.setConnectionCacheName("MyCache");
ods.setONSConfiguration((String)props.get("onsconfig"));
ods.setURL((String)props.get("url"));
occm.createCache("MyCache", ods, cacheProperties);
}
private Properties loadProperties (String file)
{
Properties prop = new Properties();
ResourceBundle bundle = ResourceBundle.getBundle(file);
Enumeration enumlist = bundle.getKeys();
String key = null;
while (enumlist.hasMoreElements())
{
key = (String) enumlist.nextElement();
prop.put(key, bundle.getObject(key));
}
return prop;
}
public void run() throws Exception
{
Connection conn = null;
Statement stmt = null;
ResultSet rset = null;
String sQuery =
"select sys_context('userenv', 'instance_name'), " +
"sys_context('userenv', 'server_host'), " +
"sys_context('userenv', 'service_name') " +
"from dual";
try
{
conn = null;
conn = ods.getConnection();
stmt = conn.createStatement();
rset = stmt.executeQuery(sQuery);
rset.next();
System.out.println("-----------");
System.out.println("Instance -> " + rset.getString(1));
System.out.println("Host -> " + rset.getString(2));
System.out.println("Service -> " + rset.getString(3));
System.out.println("NumberOfAvailableConnections: " +
occm.getNumberOfAvailableConnections("MyCache"));
System.out.println("NumberOfActiveConnections: " +
occm.getNumberOfActiveConnections("MyCache"));
System.out.println("-----------");
}
catch (SQLException sqle)
{
while (sqle != null)
{
System.out.println("SQL State: " + sqle.getSQLState());
System.out.println("Vendor Specific code: " +
sqle.getErrorCode());
Throwable te = sqle.getCause();
while (te != null) {
System.out.print("Throwable: " + te);
te = te.getCause();
}
sqle.printStackTrace();
sqle = sqle.getNextException();
}
}
finally
{
try
{
rset.close();
stmt.close();
conn.close();
}
catch (SQLException sqle2)
{
System.out.println("Error during close");
}
}
}
public static void main(String[] args)
{
System.out.println(">> PROGRAM using JDBC thin driver no oracle client required");
System.out.println(">> ojdbc14.jar and ons.jar must be in the CLASSPATH");
System.out.println(">> Press CNTRL C to exit running program\n");
try
{
FCFConnectionCacheExample test = new FCFConnectionCacheExample();
while (true)
{
test.run();
Thread.currentThread().sleep(10000);
}
}
catch (InterruptedException e)
{
System.out.println("PROGRAM Ended by user");
}
catch (Exception ex)
{
System.out.println("Error Occurred in MAIN");
ex.printStackTrace();
}
}
}
