BoneCP源码——概述

BoneCP是一个开源的Java数据库连接池，其内部使用了JDK1.5的并发包java.util.concurrent来保证同步，而且采用分段思想，避免单点加锁的竞争（ConcurrentHashMap也是使用这种思想来实现的），具有以下特点（官网）：   

• Highly scalable, fast connection pool
• Callback (hook interceptor) mechanisms on a change of connection state.
• Partitioning capability to increase performance
• Allows direct access to a connection/statements
• Automatic resizing of pool
• Statement caching support
• Support for obtaining a connection asynchronously (by returning a Future<Connection>)
• Release helper threads to release a connection/statement in an asynchronous fashion for higher performance.
• Easy mechanism to execute a custom statement on each newly obtained connection (initSQL).
• Support to switch to a new database at runtime without shutting down an application
• Ability to replay any failed transaction automatically (for the case where database/network goes down etc)
• JMX support
• Lazy initialization capable
• Support for XML/property configuration
• Idle connection timeouts / max connection age support
• Automatic validation of connections (keep-alives etc)
• Allow obtaining of new connections via a datasource rather than via a Driver
• Datasource/Hibernate support capable
• Debugging hooks to highlight the exact place where a connection was obtained but not closed
• Debugging support to show stack locations of connections that were closed twice.
• Custom pool name support.
• Clean organised code. 100% unit test branch code coverage (over 180 JUnit tests).
• Free, open source and written in 100% pure Java with complete Javadocs.

 官网上提供的跟其它连接池的性能测试对比：

Single Thread

• 1,000,000 get connection / release connection requests
• No delay between getting/releasing connection.
• Pool size range: 20-50.
• Acquire increment: 5
• Helper threads: 1
• Partition count: 1

Multi-Thread

• 500 threads each attempting 100 get/release connection
• No delay between getting/releasing connection.
• Pool size range: 50-200.
• Acquire increment: 5
• Helper threads: 5

 

 本次学习基于bonecp-0.7.1.RELEASE版本，主要jar包如下：

com.jolbox.bonecp                  连接池核心包
com.jolbox.bonecp.hooks       支持connection状态改变时的事件通知
com.jolbox.bonecp.proxy        代理java.sql.*下的接口，仅供内部使用
此版本主要依赖的外部包有：

slf4j
guava（google lib）

jsr166y

提供外部支持和测试
com.jolbox.bonecp.provider
com.jolbox.bonecp.spring