Spring TCP server

Let’s suppose that you need configure a TCP server in Spring / Spring Boot application. We will make it that the server prints the client’s request on the screen, then sends a response to the client. First, let’s include the spring-integration-ip dependency. In Maven it will look like this: Like gRPC ideology, in this case […]

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Terracotta Ehcache notes

Java has a caching standard – JCache. This standard is described in the JSR-107 specification. This standardized approach makes it easier to integrate with different tools that perform the same function. Thus, Spring Boot supports JCache integration. Therefore, whatever implementation of JCache we would use, the code remains the same. Some of the common JCache […]

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gRPC Timeouts & Deadlines

First, let’s figure out how the timeout differs from the deadline. Timeout is relative value, but deadline is absolute. If we take a timeout and a deadline of 5 seconds, and we will write the following line (the code for an example, it will not work if you run it): Then, if you want to […]

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gRPC channel for target was not shutdown properly

Imagine you are faced with an error like this: The point is that if you create a gRPC channel, you must close it after use. Let’s say you’ve already made a channel like this: After use, it will need to be closed. It is important to wait until it closes; awaitTermination() is used for this:

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How to run Scala script with Object on Spark

Suppose you have code like this in Scala: And you run it like this: And you want to put it in a Scala Object so that IntelliJ IDEA doesn’t highlight the code in red. Firstly, you are going to do smth like that: But when you run the script, nothing happens and spark2-shell just opens. […]

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Scala + Maven + IntelliJ IDEA project setup

To create a Scala project using Maven to manage dependencies in IntelliJ IDEA, you first need to install the Scala plugin: File -> Preferences (Settings) -> Plugins Search Scala in the Marketplace Install it and restart IntelliJ IDEA Next, let’s create a regular Java + Maven project: File -> New -> Project Select Maven -> […]

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