com.mysql.jdbc.exceptions.jdbc4.CommunicationsExceptionのMySQL + Apache Tomcatの7

Question

マイアプリケーション（春4 MVC /休止4/MySQLの/ Mavenの）アノテーションベースの設定を使用して休止状態と春を統合。私はいつもこのエラーが表示されたデータベースを使用していないことの数時間後：

を次のように私は定義された接続プールを使用しています

devuser@localhost:/etc/apache2$ more /etc/mysql/my.cnf 
# 
# The MySQL database server configuration file. 
# 
# You can copy this to one of: 
# - "/etc/mysql/my.cnf" to set global options, 
# - "~/.my.cnf" to set user-specific options. 
# 
# One can use all long options that the program supports. 
# Run program with --help to get a list of available options and with 
# --print-defaults to see which it would actually understand and use. 
# 
# For explanations see 
# http://dev.mysql.com/doc/mysql/en/server-system-variables.html 

# This will be passed to all mysql clients 
# It has been reported that passwords should be enclosed with ticks/quotes 
# escpecially if they contain "#" chars... 
# Remember to edit /etc/mysql/debian.cnf when changing the socket location. 
[client] 
port  = 3306 
socket  = /var/run/mysqld/mysqld.sock 

# Here is entries for some specific programs 
# The following values assume you have at least 32M ram 

# This was formally known as [safe_mysqld]. Both versions are currently parsed. 
[mysqld_safe] 
socket  = /var/run/mysqld/mysqld.sock 
nice  = 0 

[mysqld] 
# 
# * Basic Settings 
# 
user  = mysql 
pid-file = /var/run/mysqld/mysqld.pid 
socket  = /var/run/mysqld/mysqld.sock 
port  = 3306 
basedir  = /usr 
datadir  = /var/lib/mysql 
tmpdir  = /tmp 
lc-messages-dir = /usr/share/mysql 
skip-external-locking 
# 
# Instead of skip-networking the default is now to listen only on 
# localhost which is more compatible and is not less secure. 
bind-address  = 127.0.0.1 
# 
# * Fine Tuning 
# 
key_buffer  = 32M 
max_allowed_packet = 1M 
thread_stack  = 128K 
thread_cache_size  = 8 
# This replaces the startup script and checks MyISAM tables if needed 
# the first time they are touched 
myisam-recover   = BACKUP 
max_connections  = 75 
table_cache   = 32 
#thread_concurrency  = 10 
# 
# * Query Cache Configuration 
# 
query_cache_limit = 1M 
query_cache_size  = 16M 
# 
# * Logging and Replication 
# 
# Both location gets rotated by the cronjob. 
# Be aware that this log type is a performance killer. 
# As of 5.1 you can enable the log at runtime! 
#general_log_file  = /var/log/mysql/mysql.log 
#general_log    = 1 
# 
# Error log - should be very few entries. 
# 
log_error = /var/log/mysql/error.log 
# 
# Here you can see queries with especially long duration 
#log_slow_queries = /var/log/mysql/mysql-slow.log 
#long_query_time = 2 
#log-queries-not-using-indexes 
# 
# The following can be used as easy to replay backup logs or for replication. 
# note: if you are setting up a replication slave, see README.Debian about 
#  other settings you may need to change. 
#server-id  = 1 
#log_bin   = /var/log/mysql/mysql-bin.log 
expire_logs_days = 10 
max_binlog_size   = 100M 
#binlog_do_db  = include_database_name 
#binlog_ignore_db = include_database_name 
# 
# * InnoDB 
# 
# InnoDB is enabled by default with a 10MB datafile in /var/lib/mysql/. 
# Read the manual for more InnoDB related options. There are many! 
# 
# * Security Features 
# 
# Read the manual, too, if you want chroot! 
# chroot = /var/lib/mysql/ 
# 
# For generating SSL certificates I recommend the OpenSSL GUI "tinyca". 
# 
# ssl-ca=/etc/mysql/cacert.pem 
# ssl-cert=/etc/mysql/server-cert.pem 
# ssl-key=/etc/mysql/server-key.pem 



[mysqldump] 
quick 
quote-names 
max_allowed_packet = 16M 

[mysql] 
#no-auto-rehash # faster start of mysql but no tab completition 

[isamchk] 
key_buffer  = 16M 

# 
# * IMPORTANT: Additional settings that can override those from this file! 
# The files must end with '.cnf', otherwise they'll be ignored. 
# 
!includedir /etc/mysql/conf.d/ 

：

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: The last packet successfully received from the server was 84,510,841 milliseconds ago. The last packet sent successfully to the server was 84,510,841 milliseconds ago. is longer than the server configured value of 'wait_timeout'. You should consider either expiring and/or testing connection validity before use in your application, increasing the server configured values for client timeouts, or using the Connector/J connection property 'autoReconnect=true' to avoid this problem. 
    sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) 
    sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57) 
    sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) 
    java.lang.reflect.Constructor.newInstance(Constructor.java:526) 
    com.mysql.jdbc.Util.handleNewInstance(Util.java:411) 
    com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1121) 
    com.mysql.jdbc.MysqlIO.send(MysqlIO.java:3938) 
    com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2551) 
    com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731) 
    com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2809) 
    com.mysql.jdbc.ConnectionImpl.setAutoCommit(ConnectionImpl.java:5333) 
    sun.reflect.GeneratedMethodAccessor58.invoke(Unknown Source) 
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    java.lang.reflect.Method.invoke(Method.java:606) 
    org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126) 
    org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:109) 
    org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:80) 
    com.sun.proxy.$Proxy33.setAutoCommit(Unknown Source) 
    org.hibernate.resource.jdbc.internal.AbstractLogicalConnectionImplementor.begin(AbstractLogicalConnectionImplementor.java:67) 
    org.hibernate.resource.jdbc.internal.LogicalConnectionManagedImpl.begin(LogicalConnectionManagedImpl.java:238) 
    org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.begin(JdbcResourceLocalTransactionCoordinatorImpl.java:213) 
    org.hibernate.engine.transaction.internal.TransactionImpl.begin(TransactionImpl.java:52) 
    org.hibernate.internal.SessionImpl.beginTransaction(SessionImpl.java:1512) 
    org.hibernate.jpa.internal.TransactionImpl.begin(TransactionImpl.java:45) 
    org.springframework.orm.jpa.vendor.HibernateJpaDialect.beginTransaction(HibernateJpaDialect.java:170) 
    org.springframework.orm.jpa.JpaTransactionManager.doBegin(JpaTransactionManager.java:380) 
    org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373) 
    org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:427) 
    org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:276) 
    org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) 
    org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) 
    org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:208) 
    com.sun.proxy.$Proxy118.findAll(Unknown Source) 
    com.ideefe.iot.controller.AppController.listDevices(AppController.java:49) 
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) 
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    java.lang.reflect.Method.invoke(Method.java:606) 
    org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:222) 
    org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:137) 
    org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:110) 
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:814) 
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:737) 
    org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) 
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959) 
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:893) 
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) 
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:620) 
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) 
    javax.servlet.http.HttpServlet.service(HttpServlet.java:727) 
    org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:121) 
    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 
    org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77) 
    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 
    org.springframework.web.multipart.support.MultipartFilter.doFilterInternal(MultipartFilter.java:118) 
    org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) 

ここでのMySQL my.cnfファイルです

<?xml version="1.0" encoding="UTF-8"?> 
<Context> 
    <!-- Especifica un DataSource JDBC. --> 
    <Resource name="jdbc/devicesDS" 
       auth="Container" 
       type="javax.sql.DataSource" 
       maxActive="10" 
       maxIdle="4" 
       username="root" 
       password="SrbBfsatn640^" 
       driverClassName="com.mysql.jdbc.Driver" 
       url="jdbc:mysql://localhost:3306/devices?autoReconnect=true" 
       validationQuery="select 1 from dual" /> 
</Context> 

Answer 1

これはMySQL inactivity timeoutのように見えます。かなり類似したStackOverflowの質問があります（例：、）。およびhere）。すなわち、testOnBorrow=trueを追加することで、接続プールの設定を変更する助言：

<Resource name="jdbc/devicesDS" 
      auth="Container" 
      type="javax.sql.DataSource" 
      maxActive="10" 
      maxIdle="4" 
      username="root" 
      password="SrbBfsatn640^" 
      driverClassName="com.mysql.jdbc.Driver" 
      url="jdbc:mysql://localhost:3306/devices?autoReconnect=true" 
      validationQuery="select 1 from dual" 
      testOnBorrow=true /> 

前者は完全にwait_timeout値とは独立しているので、個人的にtestWhileIdleの代替上testOnBorrow方に傾くだろう - パフォーマンスが比較方法がわからなく。個人的にはエラーテキストで提案されたJDBC URL、中autoreconnect=trueの代替を使用して慎重になります - 理由のためcomment hereを参照してください。お使いのアプリケーションで

Answer 2

データベースのMySQLへの接続文字列は次のようになります。

jdbc:mysql://{host}:{port}/{schema}?autoReconnect=true 

Answer 3

は、私は他のアプリの実装でこの問題に実行して、この問題を解決する自動再=真を追加し、後にすべての設定をしようと試み、自動再など私は、これはすべての時間は、接続をリフレッシュするためにそれを強制的に、DBに対してpingを実行し、テストクエリを呼び出すスケジュールイベントを作っていた解決するために見つける 唯一の方法。

query("SELECT version()");