Course – Black Friday 2025 – NPI EA (cat= Baeldung)
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Yes, we're now running our Black Friday Sale. All Access and Pro are 33% off until 2nd December, 2025:

>> EXPLORE ACCESS NOW

Partner – Orkes – NPI EA (cat=Spring)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

Partner – Orkes – NPI EA (tag=Microservices)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

eBook – Guide Spring Cloud – NPI EA (cat=Spring Cloud)
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Let's get started with a Microservice Architecture with Spring Cloud:

>> Join Pro and download the eBook

eBook – Mockito – NPI EA (tag = Mockito)
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Mocking is an essential part of unit testing, and the Mockito library makes it easy to write clean and intuitive unit tests for your Java code.

Get started with mocking and improve your application tests using our Mockito guide:

Download the eBook

eBook – Reactive – NPI EA (cat=Reactive)
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Spring 5 added support for reactive programming with the Spring WebFlux module, which has been improved upon ever since. Get started with the Reactor project basics and reactive programming in Spring Boot:

>> Join Pro and download the eBook

eBook – Java Streams – NPI EA (cat=Java Streams)
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Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.

But these can also be overused and fall into some common pitfalls.

To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:

>> Join Pro and download the eBook

eBook – Jackson – NPI EA (cat=Jackson)
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Do JSON right with Jackson

Download the E-book

eBook – HTTP Client – NPI EA (cat=Http Client-Side)
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Get the most out of the Apache HTTP Client

Download the E-book

eBook – Maven – NPI EA (cat = Maven)
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Get Started with Apache Maven:

Download the E-book

eBook – Persistence – NPI EA (cat=Persistence)
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Working on getting your persistence layer right with Spring?

Explore the eBook

eBook – RwS – NPI EA (cat=Spring MVC)
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Building a REST API with Spring?

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Course – LS – NPI EA (cat=Jackson)
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Get started with Spring and Spring Boot, through the Learn Spring course:

>> LEARN SPRING
Course – RWSB – NPI EA (cat=REST)
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Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:

>> The New “REST With Spring Boot”

Course – LSS – NPI EA (cat=Spring Security)
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Yes, Spring Security can be complex, from the more advanced functionality within the Core to the deep OAuth support in the framework.

I built the security material as two full courses - Core and OAuth, to get practical with these more complex scenarios. We explore when and how to use each feature and code through it on the backing project.

You can explore the course here:

>> Learn Spring Security

Partner – Orkes – NPI EA (cat=Java)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

Course – LSD – NPI EA (tag=Spring Data JPA)
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Spring Data JPA is a great way to handle the complexity of JPA with the powerful simplicity of Spring Boot.

Get started with Spring Data JPA through the guided reference course:

>> CHECK OUT THE COURSE

Partner – Moderne – NPI EA (cat=Spring Boot)
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Refactor Java code safely — and automatically — with OpenRewrite.

Refactoring big codebases by hand is slow, risky, and easy to put off. That’s where OpenRewrite comes in. The open-source framework for large-scale, automated code transformations helps teams modernize safely and consistently.

Each month, the creators and maintainers of OpenRewrite at Moderne run live, hands-on training sessions — one for newcomers and one for experienced users. You’ll see how recipes work, how to apply them across projects, and how to modernize code with confidence.

Join the next session, bring your questions, and learn how to automate the kind of work that usually eats your sprint time.

Course – Black Friday 2025 – NPI (cat=Baeldung)
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Yes, we're now running our Black Friday Sale. All Access and Pro are 33% off until 2nd December, 2025:

>> EXPLORE ACCESS NOW

1. Overview

Maven is a build automation and project management tool mainly used for Java-based applications. As a result, it automates software development lifecycles, making it easier for developers to manage dependencies, compile code, run tests, and package applications effectively.

However, we may encounter an “Error in Opening Zip File” issue when using Maven commands to build an application. This issue often arises due to corrupted or inaccessible JAR files in the local Maven repository.

In this tutorial, we’ll explore various ways to resolve this issue.

2. Removing the Corrupted JAR File

Maven follows the “convention over configuration” principle to ensure a predefined project structure to avoid build and configuration errors. But, sometimes, we face an “Error in Opening Zip File” issue due to a corrupted JAR file.

2.1. Identify the Corrupted JAR

To resolve this issue, we must first identify the corrupted JAR file. In order to locate the corrupted JAR file, we need to check the build logs. These logs provide all the process details and the file’s name.

2.2. Remove the JAR File

So far, we have already figured out a process to find the culprit JAR file. We now need to remove the JAR file from the local Maven repository. To demonstrate, let’s assume we have junit-3.8.1.jar as a corrupted file:

$ rm -rf /Home/ubuntu/.m2/repository/junit/junit/3.8.1/junit-3.8.1.jar

By using the above command, the junit-3.8.1.jar file will be removed from the local Maven repository.

2.3. Rebuild the Project

The corrupted JAR file has already been removed from the local Maven repository. Let’s rebuild the project using the mvn command:

$ mvn clean install

By running the above command, the project will be rebuilt, and Maven will search for the junit-3.8.1.jar dependency in the local repository. Since it won’t be able to get it from the local repository, it will download it from the remote repository.

3. Clearing the Local Repository

If there are multiple JAR files leading to this issue, then we need to clean the entire local Maven repository. Therefore, we’ll remove all the JAR files kept in the local Maven repository. By doing this, we ensure that we have the latest version of the dependencies and there are no conflicts due to multiple versions of the same JAR file.

3.1. Backup Local Repository

Before proceeding to remove the existing /.m2/repository/ directory. Moreover, we should first take a backup of this repository to prevent any data loss. As an outcome, it ensures that we have a copy of the required dependencies in our local repository.

3.2. Delete the Local Repository

By deleting the local Maven repository, all cached dependencies will be cleared. Since all the dependencies must be redownloaded again, this process can be time-consuming. To demonstrate, let’s look at the command to clean the whole repository:

$ rm -rf /.m2/repository/

The above command will simply remove all the dependencies present in the /.m2/repository/ directory.

3.3. Rebuild the Project

As we have already cleaned the entire repository, let’s run the command to build the project again:

$ mvn clean install

Using this command, Maven will fetch all the dependencies from the remote repository and add them to the local repository.

4. Conclusion

In this article, we explored different ways to resolve the “Error in Opening Zip File” issue. First, we looked at removing the particular corrupted JAR file. After that, we resolved the issue by completely deleting the entire local Maven repository.

Course – Black Friday 2025 – NPI EA (cat= Baeldung)
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Yes, we're now running our Black Friday Sale. All Access and Pro are 33% off until 2nd December, 2025:

>> EXPLORE ACCESS NOW

Partner – Orkes – NPI EA (cat = Spring)
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Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

Partner – Orkes – NPI EA (tag = Microservices)
announcement - icon

Modern software architecture is often broken. Slow delivery leads to missed opportunities, innovation is stalled due to architectural complexities, and engineering resources are exceedingly expensive.

Orkes is the leading workflow orchestration platform built to enable teams to transform the way they develop, connect, and deploy applications, microservices, AI agents, and more.

With Orkes Conductor managed through Orkes Cloud, developers can focus on building mission critical applications without worrying about infrastructure maintenance to meet goals and, simply put, taking new products live faster and reducing total cost of ownership.

Try a 14-Day Free Trial of Orkes Conductor today.

eBook – HTTP Client – NPI EA (cat=HTTP Client-Side)
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The Apache HTTP Client is a very robust library, suitable for both simple and advanced use cases when testing HTTP endpoints. Check out our guide covering basic request and response handling, as well as security, cookies, timeouts, and more:

>> Download the eBook

eBook – Java Concurrency – NPI EA (cat=Java Concurrency)
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Handling concurrency in an application can be a tricky process with many potential pitfalls. A solid grasp of the fundamentals will go a long way to help minimize these issues.

Get started with understanding multi-threaded applications with our Java Concurrency guide:

>> Download the eBook

eBook – Java Streams – NPI EA (cat=Java Streams)
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Since its introduction in Java 8, the Stream API has become a staple of Java development. The basic operations like iterating, filtering, mapping sequences of elements are deceptively simple to use.

But these can also be overused and fall into some common pitfalls.

To get a better understanding on how Streams work and how to combine them with other language features, check out our guide to Java Streams:

>> Join Pro and download the eBook

eBook – Persistence – NPI EA (cat=Persistence)
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Working on getting your persistence layer right with Spring?

Explore the eBook

Course – LS – NPI EA (cat=REST)

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Get started with Spring Boot and with core Spring, through the Learn Spring course:

>> CHECK OUT THE COURSE

Partner – Moderne – NPI EA (tag=Refactoring)
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Modern Java teams move fast — but codebases don’t always keep up. Frameworks change, dependencies drift, and tech debt builds until it starts to drag on delivery. OpenRewrite was built to fix that: an open-source refactoring engine that automates repetitive code changes while keeping developer intent intact.

The monthly training series, led by the creators and maintainers of OpenRewrite at Moderne, walks through real-world migrations and modernization patterns. Whether you’re new to recipes or ready to write your own, you’ll learn practical ways to refactor safely and at scale.

If you’ve ever wished refactoring felt as natural — and as fast — as writing code, this is a good place to start.

Course – Black Friday 2025 – NPI (All)
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Yes, we're now running our Black Friday Sale. All Access and Pro are 33% off until 2nd December, 2025:

>> EXPLORE ACCESS NOW

eBook Jackson – NPI EA – 3 (cat = Jackson)