Java. Lang. noclassdeffounderror: cocould not initialize class com. MySQL. JDBC. connectionimpl

Exception in thread "com. mchange. v2.async. threadpoolasynchronousrunner $ poolthrea
D-#2 "Java. Lang. noclassdeffounderror: cocould not initialize class com. MySQL. JDBC. connectionimpl

 

Sqlclientinfoexception is only available in JDK 6.0

 

 

The solution to the error is as follows: According to the error message, the "Java/SQL/sqlclientinfoexception" information cannot be found. First, check whether the JDK version has the sqlclientinfoexception class (according to the introduction on the network, this category is available only in JDK 6 or later versions !). Although this type of file exists in the JDK6-API, it does not necessarily exist in JDK 6 installed on your machine (JDK 6 or below is more likely to have this category ), A convenient confirmation method is to go to the JDK installation path on your machine and check whether the source file "sqlclientinfoexception" is found in the path "Java/SQL/" in the "/src.zip" source file package. java "if not, it indicates that the JDK you installed does not contain such files (take the JDK on your machine as an example, although it is version 1.6 ["Java version" 1.6.0-rc-b66 ""], but there is no such file), therefore, "Java/SQL/sqlclientinfoexception" always occurs during database connection! I copied a later version of the "% java_home %/jrelib/RT. Jar" file (JDK version containing the "Java/SQL/sqlclientinfoexception" class file !) Replace the corresponding file on the local machine and execute the program. It's okay. It's successful!