Maven import static constant cannot find symbol

Suppose you have a class with constants: And you made the static import of this constant in another class: Everything looks good, and IDEA does not show any mistakes (in fact, there are really no errors in code). But Maven suddenly failed building project with cannot find symbol error. This situation can arise because there […]

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Jackson Mismatched Input Exception

Suppose you are trying to do something like: But the output is something like: There are at least two reasons: Configuration file does not exist; Setters for MyConfiguration.class are named incorrectly or cannot be accessed.

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Using gRPC with JKS

gRPC doesn’t support JKS out of the box, but there is a workaround. Below is an example of how to use gRPC and JKS. Server side Client side If you don’t need to use custom truststore, you need to do nothing. If you need to use custom truststore, use example below: You can use trustManagerFactory […]

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OPENSSL internal: SSLV3 ALERT HANDSHAKE FAILURE

Full text of the error: If you encounter such an error, there are at least two reasons: Incompatible version of boring-ssl library. Private key problem. For example, we wrote our own KeyManager implementation and the getPrivateKey() method returns null, or there is no such private key at all.

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Apache Curator: Invalid config event received

The exception looks like this: We know, that in zookeeper.properties (or zoo.cfg) there is a cluster configuration of the following type: From a certain version of ZooKeeper, it became like this https://zookeeper.apache.org/doc/r3.5.3-beta/zookeeperReconfig.html#ch_reconfig_format: Apache Curator switched to a new format, discontinuing support for the old one. However, ZooKeeper kept it: on the same page in the […]

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Keytab encryption types list

Let’s imagine that we needed to determine what principles and what encryption types exist in a certain keytab. To do this, we will use the ktutil utility: After we have entered the CLI of this utility, we type the following commands: Something like this will be displayed:

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Error while calling a method on a Groovy class

You may encounter an error when compiling your project that looks like this: It is not at all clear what class are meant. If you work with IntelliJ IDEA – this is the reason. Sometime it parses maven build/compile logs incorrectly, so the second part of the exception was lost. Compile manually through the terminal […]

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