Error: Could not initialize class ru.yandex.clickhouse.ClickHouseUtil - jdbc

Question

I'm using clickhouse-jdbc in my java application. And I'm adding it to pom.xml like this:
<dependency>
<groupId>ru.yandex.clickhouse</groupId>
<artifactId>clickhouse-jdbc</artifactId>
<version>0.1.34</version>
</dependency>
And when I run my java application java -jar myapp.jar. It's throwing:
java.lang.NoClassDefFoundError: Could not initialize class
ru.yandex.clickhouse.ClickHouseUtil
And in my packaged jar file, there is also ClickHouseUtil.class. And I'm using Intellij Idea for packaging jar. How can I fix this issue?

Answer 1

The error 'Could not initialize class ....' means that the JVM has already tried and failed to perform static initialization of the class mentioned.
Static initialization of a class involves assigning values to any static fields and running any static { ... } blocks. The class in question is ru.yandex.clickhouse.ClickHouseUtil, and static initialization of this class consists only of setting up the static final field CLICKHOUSE_ESCAPER. This appears to rely on a couple of Guava escaper classes (com.google.common.escape.Escaper and com.google.common.escape.Escapers).
So I suspect that these Guava classes aren't in your packaged JAR file.
It's also worth pointing out that the exception message 'Could not initialize class ....' means that static initialization has already failed. In other words, when this exception is thrown, it is at least the second time the JVM has failed to load the class. It's possible that your app may have reported a more informative error message when the JVM failed to load this class for the first time.