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Once the early-adopter seats are all used, the price will go up and stay at $33/year.

Partner – Microsoft – NPI EA (cat = Baeldung)
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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

Of course, Azure Container Apps has really solid support for our ecosystem, from a number of build options, managed Java components, native metrics, dynamic logger, and quite a bit more.

To learn more about Java features on Azure Container Apps, visit the documentation page.

You can also ask questions and leave feedback on the Azure Container Apps GitHub page.

Partner – Microsoft – NPI EA (cat= Spring Boot)
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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

Of course, Azure Container Apps has really solid support for our ecosystem, from a number of build options, managed Java components, native metrics, dynamic logger, and quite a bit more.

To learn more about Java features on Azure Container Apps, you can get started over on the documentation page.

And, you can also ask questions and leave feedback on the Azure Container Apps GitHub page.

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.

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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.

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eBook – Guide Spring Cloud – NPI EA (cat=Spring Cloud)
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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.

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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.

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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:

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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:

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

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eBook – HTTP Client – NPI EA (cat=Http Client-Side)
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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:

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Explore Spring Boot 3 and Spring 6 in-depth through building a full REST API with the framework:

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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:

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Course – All Access – NPI EA (cat= Spring)
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All Access is finally out, with all of my Spring courses. Learn JUnit is out as well, and Learn Maven is coming fast. And, of course, quite a bit more affordable. Finally.

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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.

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Partner – LambdaTest – NPI EA (cat=Testing)
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End-to-end testing is a very useful method to make sure that your application works as intended. This highlights issues in the overall functionality of the software, that the unit and integration test stages may miss.

Playwright is an easy-to-use, but powerful tool that automates end-to-end testing, and supports all modern browsers and platforms.

When coupled with LambdaTest (an AI-powered cloud-based test execution platform) it can be further scaled to run the Playwright scripts in parallel across 3000+ browser and device combinations:

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eBook – Java Concurrency – NPI (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.

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1. Overview

In this tutorial, we’ll discuss various ways to capture the thread dump of a Java application.

A thread dump is a snapshot of the state of all the threads of a Java process. The state of each thread is presented with a stack trace, showing the content of a thread’s stack. A thread dump is useful for diagnosing problems, as it displays the thread’s activity. Thread dumps are written in plain text, so we can save their contents to a file and look at them later in a text editor.

In the next sections, we’ll go through multiple tools and approaches to generate a thread dump.

2. Using JDK Utilities

The JDK provides several utilities that can capture the thread dump of a Java application. All of the utilities are located under the bin folder inside the JDK home directory. Therefore, we can execute these utilities from the command line as long as this directory is in our system path.

2.1. jstack

jstack is a command-line JDK utility we can use to capture a thread dump. It takes the pid of a process and displays the thread dump in the console. Alternatively, we can redirect its output to a file.

Let’s take a look at the basic command syntax for capturing a thread dump using jstack:

jstack [-F] [-l] [-m] <pid>

All the flags are optional. Let’s see what they mean:

  • -F option forces a thread dump; handy to use when jstack pid doesn’t respond (the process is hung)
  • -l option instructs the utility to look for ownable synchronizers in the heap and locks
  • -m option prints native stack frames (C & C++) in addition to the Java stack frames

Let’s put this knowledge to use by capturing a thread dump and redirecting the result to a file:

jstack 17264 > /tmp/threaddump.txt

Remember that we can easily get the pid of a Java process by using the jps command.

2.2. Java Mission Control

Java Mission Control (JMC) is a GUI tool that collects and analyzes data from Java applications. After we launch JMC, it displays the list of Java processes running on a local machine. We can also connect to remote Java processes through JMC.

We can right-click on the process and click on the “Start Flight Recording” option. After this, the Threads tab shows the Thread Dumps:

JMC

2.3. jvisualvm

jvisualvm is a tool with a graphical user interface that lets us monitor, troubleshoot, and profile Java applications. The GUI is simple, but very intuitive and easy to use.

One of its many options allows us to capture a thread dump. If we right-click on a Java process and select the “Thread Dump” option, the tool will create a thread dump and open it in a new tab:

JVisualVM

As of JDK 9, Visual VM isn’t included in the Oracle JDK and Open JDK distributions. Therefore, if we’re using Java 9 or newer versions, we can get the JVisualVM from the Visual VM open source project site.

2.4. jcmd

jcmd is a tool that works by sending command requests to the JVM. Although powerful, it doesn’t contain any remote functionality; we have to use it in the same machine where the Java process is running.

One of its many commands is Thread.print. We can use it to get a thread dump just by specifying the pid of the process:

jcmd 17264 Thread.print

2.5. jconsole

jconsole lets us inspect the stack trace of each thread. If we open jconsole and connect to a running Java process, we can navigate to the Threads tab and find each thread’s stack trace:

JConsole

2.6. Summary

As it turns out, there are many ways to capture a thread dump using JDK utilities. Let’s take a moment to reflect on each and outline their pros and cons:

  • jstack: provides the quickest and easiest way to capture a thread dump; however, better alternatives are available starting with Java 8
  • jmc: enhanced JDK profiling and diagnostics tool. It minimizes the performance overhead that’s usually an issue with profiling tools.
  • jvisualvm: lightweight and open-source profiling tool with an excellent GUI console
  • jcmd: extremely powerful and recommended for Java 8 and later. A single tool that serves many purposes: capturing thread dump (jstack), heap dump (jmap), system properties, and command-line arguments (jinfo)
  • jconsole: lets us inspect thread stack trace information

3. From the Command Line

In enterprise application servers, only the JRE is installed for security reasons. Thus, we can’t use the above-mentioned utilities, as they’re part of JDK. However, there are various command-line alternatives that let us capture thread dumps easily.

3.1. kill -3 Command (Linux/Unix)

The easiest way to capture a thread dump in Unix-like systems is through the kill command, which we can use to send a signal to a process using the kill() system call. In this use case, we’ll send it the -3 signal.

Using our same pid from earlier examples, let’s take a look at how to use kill to capture a thread dump:

kill -3 17264

This way the signal-receiving Java process will print the thread dump on the standard output.

If we run the Java process with the following combination of tuning flags, then it’ll also redirect the thread dump to the given file:

-XX:+UnlockDiagnosticVMOptions -XX:+LogVMOutput -XX:LogFile=~/jvm.log

Now if we send the -3 signal, in addition to the standard output, the dump will be available at ~/jvm.log file.

3.2. Ctrl + Break (Windows)

In Windows operating systems, we can capture a thread dump using the CTRL and Break key combination. To take a thread dump, navigate to the console used to launch the Java application, and press the CTRL and Break keys together.

It’s worth noting that, on some keyboards, the Break key isn’t available. Therefore, in such cases, a thread dump can be captured using the CTRL, SHIFT, and Pause keys together.

Both of these commands print the thread dump to the console.

4. Programmatically Using ThreadMxBean

The last approach we’ll discuss in this article is using JMX. We’ll use ThreadMxBean to capture the thread dump. Let’s see it in code:

private static String threadDump(boolean lockedMonitors, boolean lockedSynchronizers) {
    StringBuffer threadDump = new StringBuffer(System.lineSeparator());
    ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
    for(ThreadInfo threadInfo : threadMXBean.dumpAllThreads(lockedMonitors, lockedSynchronizers)) {
        threadDump.append(threadInfo.toString());
    }
    return threadDump.toString();
}

In the above program, we’re performing several steps:

  1. At first, an empty StringBuffer is initialized to hold the stack information of each thread.
  2. We then use the ManagementFactory class to get the instance of ThreadMxBean. A ManagementFactory is a factory class for getting managed beans for the Java platform. In addition, a ThreadMxBean is the management interface for the thread system of the JVM.
  3. Setting lockedMonitors and lockedSynchronizers values to true indicates to capture the ownable synchronizers and all locked monitors in the thread dump.

5. Conclusion

In this article, we learned multiple ways to capture a thread dump.

First, we discussed various JDK Utilities, and then the command-line alternatives. Finally, we concluded with the programmatic approach using JMX.

The code backing this article is available on GitHub. Once you're logged in as a Baeldung Pro Member, start learning and coding on the project.
Baeldung Pro – NPI EA (cat = Baeldung)
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Baeldung Pro comes with both absolutely No-Ads as well as finally with Dark Mode, for a clean learning experience:

>> Explore a clean Baeldung

Once the early-adopter seats are all used, the price will go up and stay at $33/year.

Partner – Microsoft – NPI EA (cat = Spring Boot)
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Azure Container Apps is a fully managed serverless container service that enables you to build and deploy modern, cloud-native Java applications and microservices at scale. It offers a simplified developer experience while providing the flexibility and portability of containers.

Of course, Azure Container Apps has really solid support for our ecosystem, from a number of build options, managed Java components, native metrics, dynamic logger, and quite a bit more.

To learn more about Java features on Azure Container Apps, visit the documentation page.

You can also ask questions and leave feedback on the Azure Container Apps GitHub page.

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 – 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:

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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:

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

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Course – LS – NPI EA (cat=REST)

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Course – Spring Sale 2025 – NPI EA (cat= Baeldung)
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Course – Spring Sale 2025 – NPI (All)
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eBook – Java Concurrency – NPI (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 Jackson – NPI EA – 3 (cat = Jackson)