多线程Java程序中的连接池

Question

I have a java process which is multi threaded using ExecutorService (15 threads). Each thread calls stored procedure to insert data to table, my connection to be pooled across 15 threads so that I could see multiple commits on the table at the same time, but i only see one connection established for one active thread even through 15 threads are ready and waiting.

Tried using the below code to establish connection and pooled across all threads

Class.forName(DB_DRIVER);

DataSource oracleDataSource = new DriverManagerDataSource(DB_CONNECTION, DB_USER,DB_PASSWORD);

ObjectPool objectPool = new GenericObjectPool();

DataSourceConnectionFactory datasourceConnectionFactory = new DataSourceConnectionFactory(oracleDataSource);

PoolableConnectionFactory poolableConnectionFactory = new PoolableConnectionFactory(datasourceConnectionFactory, objectPool, null, null, false, true);

objectPool.setFactory(poolableConnectionFactory);

PoolingDataSource datasource = new PoolingDataSource(objectPool); 

but it didn't work still. Still my threads are using only one connection and other threads are waiting for the active one to complete.

Answer 1

You could encapsulate the connection to the DB in a class and create a pool of objects of this class yourself.

Example

class Connection {
//  your DB connection specific stuff
public void open() {
//  open connection
}

public void close() {
// close connection
}

public void isOpen() {
//  is the connection being opened by any thread already
}
}

Once you have this, create a thread safe method which will return the next available connection object to any requesting thread.

class ConnectionController {
public Connection getConnection() {
//  return the next available connection object by checking which 
//connection object is not open by checking return value of isOpen
}
}

Make sure you close the connection once you are done! Hope it helps.