带有 Cloud SQL 的应用引擎上的连接池 [英] Connection pool on app engine with Cloud SQL

问题描述

听起来像应用引擎 (1) 的更新云 SQL JDBC 驱动程序支持连接池.

It sounds like the newer cloud SQL JDBC drivers for app engine (1) support connection pooling.

我们的应用程序使用 Spring+Hibernate，我们正在尝试使用现有的 Java 框架之一进行连接池(BoneCP、C3p0、Hikari)，但由于应用程序引擎的限制，迄今为止未能使用其中任何一个.下面使用 Spring+Hibernate+C3p0 进行堆栈跟踪.有没有人设法让这个工作?

Our app uses Spring+Hibernate and we're trying to use one of the existing java frameworks for connection pooling (BoneCP, C3p0, Hikari), and have failed so far to use any of them because of app engine limitations. Stack trace using Spring+Hibernate+C3p0 below. Did anyone manage to get this to work?

[INFO] java.lang.NoClassDefFoundError: java.lang.management.ManagementFactory is a restricted class. Please see the Google  App Engine developer's guide for more details.
[INFO]  at com.google.appengine.tools.development.agent.runtime.Runtime.reject(Runtime.java:51)
[INFO]  at com.mchange.v2.c3p0.management.ActiveManagementCoordinator.<init>(ActiveManagementCoordinator.java:54)
[INFO]  at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
[INFO]  at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
[INFO]  at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
[INFO]  at java.lang.reflect.Constructor.newInstance(Constructor.java:526)
[INFO]  at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance_(Runtime.java:127)
[INFO]  at com.google.appengine.tools.development.agent.runtime.Runtime.newInstance(Runtime.java:148)
[INFO]  at com.mchange.v2.c3p0.C3P0Registry.<clinit>(C3P0Registry.java:146)
[INFO]  at java.lang.Class.forName0(Native Method)
[INFO]  at java.lang.Class.forName(Class.java:190)
[INFO]  at com.google.appengine.tools.development.agent.runtime.RuntimeHelper.checkRestricted(RuntimeHelper.java:70)
[INFO]  at com.google.appengine.tools.development.agent.runtime.Runtime.checkRestricted(Runtime.java:64)
[INFO]  at com.mchange.v2.c3p0.impl.DriverManagerDataSourceBase.<init>(DriverManagerDataSourceBase.java:212)
[INFO]  at com.mchange.v2.c3p0.DriverManagerDataSource.<init>(DriverManagerDataSource.java:72)
....

(1):旧驱动程序 = com.google.appengine.api.rdbms.AppEngineDriver.新驱动程序 = com.mysql.jdbc.GoogleDriver.

(1): Old driver = com.google.appengine.api.rdbms.AppEngineDriver. New driver = com.mysql.jdbc.GoogleDriver.

推荐答案

我们最终通过使用 Tomcat DBCP (http://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html).大多数其他池的问题在于它们使用线程，应用引擎的模型在前端实例(即长寿命线程)上阻止了线程.

We ended up solving this by using Tomcat DBCP (http://tomcat.apache.org/tomcat-7.0-doc/jdbc-pool.html). The problem with most other pools is that they use threading, which app engine's model prevent on frontend instances (long-lived threads that is).

这篇关于带有 Cloud SQL 的应用引擎上的连接池的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！