gudusoft.gsqlparser

Class TParserPool

Object

gudusoft.gsqlparser.TParserPool

Direct Known Subclasses:

TSafeParserPool

public class TParserPool
extends Object

Thread-safe parser pool implementation to replace the singleton pattern. This pool dramatically improves performance in multi-threaded environments by eliminating synchronized method bottlenecks. Each database vendor has its own pool of parser instances that can be borrowed and returned for reuse.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	TParserPool.ParserFunction<T> Functional interface for parser operations.
static class	TParserPool.PoolStatistics Pool statistics for monitoring.
static class	TParserPool.TimeoutException Custom exception for timeout scenarios.

Constructor Summary

Constructors

Constructor and Description
TParserPool() Creates a parser pool with default size
TParserPool(int poolSize) Creates a parser pool with specified size

Method Summary

Modifier and Type	Method and Description
TGSqlParser	borrowParser(EDbVendor vendor) Borrows a parser from the pool for the specified vendor.
TParserPool.PoolStatistics	getStatistics(EDbVendor vendor) Gets pool statistics for monitoring.
void	prewarm(EDbVendor vendor, int count) Pre-warms the pool by creating parsers in advance.
void	returnParser(EDbVendor vendor, TGSqlParser parser) Returns a parser to the pool for reuse.
void	shutdown() Shuts down the pool and clears all parsers.
<T> T	withParser(EDbVendor vendor, TParserPool.ParserFunction<T> function) Executes a function with a borrowed parser and automatically returns it.

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

TParserPool

public TParserPool()

Creates a parser pool with default size

TParserPool

public TParserPool(int poolSize)

Creates a parser pool with specified size

Parameters:

poolSize - Size of the pool for each vendor

Method Detail

borrowParser

public TGSqlParser borrowParser(EDbVendor vendor)
                         throws InterruptedException

Borrows a parser from the pool for the specified vendor. If no parser is available, creates a new one up to the pool limit.

Parameters:

vendor - Database vendor

Returns:

Parser instance

Throws:

InterruptedException - if interrupted while waiting

returnParser

public void returnParser(EDbVendor vendor,
                         TGSqlParser parser)

Returns a parser to the pool for reuse.

Parameters:

vendor - Database vendor

parser - Parser instance to return

withParser

public <T> T withParser(EDbVendor vendor,
                        TParserPool.ParserFunction<T> function)
                 throws Exception

Executes a function with a borrowed parser and automatically returns it. This is the recommended way to use the pool.

Parameters:

vendor - Database vendor

function - Function to execute with the parser

Returns:

Result of the function

Throws:

Exception

getStatistics

public TParserPool.PoolStatistics getStatistics(EDbVendor vendor)

Gets pool statistics for monitoring.

prewarm

public void prewarm(EDbVendor vendor,
                    int count)

Pre-warms the pool by creating parsers in advance. This avoids the initialization cost during actual usage.

Parameters:

vendor - Database vendor

count - Number of parsers to pre-create (up to poolSize)

shutdown

public void shutdown()

Shuts down the pool and clears all parsers.