MySQL SpringBoot:GenericJDBCException: 无法获取 JDBC 连接
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原文地址: http://stackoverflow.com/questions/42746872/
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SpringBoot:GenericJDBCException: Unable to acquire JDBC Connection
提问by AndroidDev
I am connecting to mysql database by creating DataSource dynamically with following properties, Its working fine, but after some time it keeps giving me the error "Unable to acquire JDBC Connection".
我通过使用以下属性动态创建 DataSource 连接到 mysql 数据库，它工作正常，但一段时间后它一直给我错误“无法获取 JDBC 连接”。
package com.test.db;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
import org.springframework.orm.jpa.JpaTransactionManager;
import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
import org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter;
import org.springframework.transaction.PlatformTransactionManager;
import java.util.HashMap;
@Configuration
@EnableJpaRepositories(basePackages = "com.test.master", entityManagerFactoryRef = "userMasterEntityManager", transactionManagerRef = "userMasterTransactionManager")
public class MasterDBConfig {
@Bean
@Primary
public LocalContainerEntityManagerFactoryBean userMasterEntityManager() {
LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
em.setDataSource(dataSource());
em.setPackagesToScan(new String[] { "com.test.master" });
HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
em.setJpaVendorAdapter(vendorAdapter);
HashMap<String, Object> properties = new HashMap<>();
properties.put("hibernate.hbm2ddl.auto", "create");
properties.put("hibernate.id.new_generator_mappings", "false");
properties.put("hibernate.show_sql", "true");
properties.put("hibernate.dialect", "org.hibernate.dialect.MySQL5Dialect");
properties.put("hibernate.testOnBorrow", "true");
properties.put("hibernate.validationQuery", "SELECT 1");
properties.put("hibernate.testWhileIdle", "true");
// properties.put("hibernate.timeBetweenEvictionRunsMillis", "3600000");
properties.put("hibernate.connection.autoReconnect", "true");
properties.put("hibernate.connection.autoReconnectForPools", "true");
em.setJpaPropertyMap(properties);
return em;
}
@Primary
@Bean(name = "dataSource")
public DataSourceRouter dataSource() {
return new DataSourceRouter();
}
@Primary
@Bean
public PlatformTransactionManager userMasterTransactionManager() {
JpaTransactionManager transactionManager = new JpaTransactionManager();
transactionManager.setEntityManagerFactory(userMasterEntityManager().getObject());
return transactionManager;
}
}
Its been hosted in AWS with Tomcat environment. DB is in RDS of AWS.
它托管在带有 Tomcat 环境的 AWS 中。DB 在 AWS 的 RDS 中。
UPDATE:
Caused by:
更新：
引起：
com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Too many connections
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.Util.getInstance(Util.java:408)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3970)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3906)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:873)
at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1710)
at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1226)
at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2253)
at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2284)
at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2083)
at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:806)
at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)
at sun.reflect.GeneratedConstructorAccessor39.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)
at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:410)
at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:328)
at org.apache.tomcat.jdbc.pool.PooledConnection.connectUsingDriver(PooledConnection.java:310)
at org.apache.tomcat.jdbc.pool.PooledConnection.connect(PooledConnection.java:203)
at org.apache.tomcat.jdbc.pool.ConnectionPool.createConnection(ConnectionPool.java:732)
at org.apache.tomcat.jdbc.pool.ConnectionPool.borrowConnection(ConnectionPool.java:664)
at org.apache.tomcat.jdbc.pool.ConnectionPool.init(ConnectionPool.java:479)
at org.apache.tomcat.jdbc.pool.ConnectionPool.<init>(ConnectionPool.java:154)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.pCreatePool(DataSourceProxy.java:118)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.createPool(DataSourceProxy.java:107)
at org.apache.tomcat.jdbc.pool.DataSourceProxy.getConnection(DataSourceProxy.java:131)
回答by Reborn
What I've learnt from your stacktrace, you have issue with too many connections which leads to unavailability to establish any new connections.The solution is quite simple - you have to setup connection pool(c3p0 is quite popular) and specify pool connections.
See thishow to setup c3p0 connection and make basic tweak.
我从您的堆栈跟踪中了解到，您遇到连接过多的问题，导致无法建立任何新连接。解决方案非常简单 - 您必须设置连接池（c3p0 非常流行）并指定池连接。
见该如何设置C3P0连接，并进行基本的调整。
Also do not forget to include dependencyfor that
另外不要忘了包括依赖该
回答by omkar sirra
For me, the problem solved by making sure that all the sessions are closed properly immediately after use.
对我来说，通过确保所有会话在使用后立即正确关闭来解决问题。
