Com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Com

An issue occurred while connecting to MySQL through JDBC. com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Communicationslinkfailurecom. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Commu

Environment RedHat Linux 9 VWWare 8.0 SSH 3.2.9 Putty 0.62 MySQL 3.2 Problem com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Communications link failure com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Commu

Environment

RedHat Linux 9 + VWWare 8.0 + SSH 3.2.9 + Putty 0.62 + MySQL 3.2

Problem

Com. MySQL. JDBC. exceptions. jdbc4.CommunicationsException: Communications link failure occurs when you connect to mysql through jdbc.

com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failureThe last packet successfully received from the server was 276 milliseconds ago.  The last packet sent successfully to the server was 50 milliseconds ago.        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)        at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)        at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1116)        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3591)        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3480)        at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4021)        at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2490)        at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2651)        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2671)        at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2621)        at com.mysql.jdbc.StatementImpl.executeQuery(StatementImpl.java:1557)        at com.mysql.jdbc.ConnectionImpl.loadServerVariables(ConnectionImpl.java:3892)        at com.mysql.jdbc.ConnectionImpl.initializePropsFromServer(ConnectionImpl.java:3437)        at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2437)        at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2207)        at com.mysql.jdbc.ConnectionImpl.
 
  (ConnectionImpl.java:797)        at com.mysql.jdbc.JDBC4Connection.
  
   (JDBC4Connection.java:47)        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)        at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)        at java.lang.reflect.Constructor.newInstance(Constructor.java:513)        at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)        at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:389)        at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:305)        at java.sql.DriverManager.getConnection(DriverManager.java:582)        at java.sql.DriverManager.getConnection(DriverManager.java:185)        at TestJDBC.getConnection(TestJDBC.java:19)        at TestJDBC.testResult(TestJDBC.java:76)        at TestJDBC.main(TestJDBC.java:13)Caused by: java.io.EOFException: Can not read response from server. Expected to read 4 bytes, read 0 bytes before connection was unexpectedly lost.        at com.mysql.jdbc.MysqlIO.readFully(MysqlIO.java:3041)        at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3491)        ... 25 morejava.lang.NullPointerException        at TestJDBC.testResult(TestJDBC.java:77)        at TestJDBC.main(TestJDBC.java:13)
  
 

Solution

Not completed. For more information, see. It is estimated that the MySQL version is a problem.

References

Com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Communications link failure

Http://stackoverflow.com/questions/2983248/com-mysql-jdbc-exceptions-jdbc4-communicationsexception-communications-link-fai

MySQL returns an error when the first connection times out the next morning. Solution: com. mysql. jdbc. exceptions. jdbc4.CommunicationsException:

Http://zeusami.iteye.com/blog/1112827

Mysql connects to com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Communications link

Http://blog.sina.com.cn/s/blog_49cc672f0100w5fb.html

Configuration of jsp environment in linux (mysql DATA driver supported)

Http://www.haogongju.net/art/356469

Caused by: com. mysql. jdbc. exceptions. jdbc4.CommunicationsException: Communications link failure

Http://blog.csdn.net/nemo2011/article/details/6526121