Java Evolution: Decoding Java 8 vs Java 17

Java 8 vs Java 17

  • Java 8: Introduced lambda expressions and streams, focusing on functional programming enhancements and performance improvements for the time.
  • Java 17: Offers advanced features like sealed classes, pattern matching, and enhanced switch expressions; significant improvements in garbage collection and overall performance; designated as a Long-Term Support (LTS) version.

Introduction Java 8 vs Java 17

java 7 vs 17

When considering the evolution of Java, a critical comparison often arises between Java 8 and Java 17.

This article aims to dissect these versions comprehensively, addressing the key aspects that every Java developer and enthusiast should know.

The primary focus is to:

  • Unveil the advancements: Understanding how Java has evolved from Java 8 to Java 17 is crucial for developers to leverage the full potential of Java in modern applications.
  • Identify the differences: Highlighting the differences helps make informed decisions about version upgrades and adopting new features.
  • Acknowledge the impact: Assessing the impact of these changes on software development practices and performance optimization.

Historical Context: Java’s Journey from Java 8 to Java 17

Significant milestones and technological advancements have marked Java’s journey from Java 8 to Java 17.

This evolution reflects the Java community’s response to the changing software development landscape.

The journey includes:

  1. The End of Oracle Premier Support for Java 8: One of the most crucial aspects of this transition was the end of Oracle’s Premier Support for Java 8. This shift signaled a push towards newer versions, encouraging developers to upgrade to benefit from continued support and advancements.
  2. Introduction of Long-Term Support (LTS) Versions: Java 17 is designated an LTS version, a critical factor for enterprises considering stability and long-term viability. LTS versions receive extended support, making them reliable for large-scale and critical applications.
  3. Progressive Introduction of New Features: The journey from Java 8 to Java 17 wasn’t just about support changes. It introduced new features, enhancing the language’s capabilities and offering developers tools to write more efficient and readable code. Key features included the introduction of lambda expressions in Java 8 and sealed classes in Java 17.
  4. Performance Optimizations: A core focus of Java’s evolution has been performance optimization. Each version improved speed, efficiency, and resource management, making Java more suitable for high-performance computing environments.
  5. Increased Emphasis on Security and Robustness: As cyber threats evolved, so did Java’s security features. Java enhanced its security model with each version, offering more robust protection against vulnerabilities and attacks.
  6. Enhancing Developer Productivity and Code Maintainability: New language features, improved garbage collection mechanisms, and enhanced APIs in Java 17 boosted developer productivity and made code more maintainable and scalable.

New Features in Java 17

As we delve into the comparison of Java 8 and Java 17, a standout aspect of Java 17 is the introduction of several impactful features.

These enhancements improve the language’s functionality and streamline the development process, making Java more efficient and developer-friendly.

  • Sealed Classes and Interfaces: A major addition in Java 17 is the concept of sealed classes and interfaces. This feature introduces a way to control which other classes or interfaces may extend or implement them. By declaring a class or an interface as ‘sealed’, developers can specify a restricted set of other types that can extend or implement it. This enhances type safety and provides a more declarative approach to type hierarchies, making code more predictable and less prone to errors.
  • Enhanced instanceOf Operator: Java 17 brings a refined version of the instanceOf operator. This enhancement simplifies the common coding pattern of checking an object’s type and casting it to that type. The new instanceOf operator combines these steps, reducing boilerplate code and improving code readability.
  • Switch Expressions and Pattern Matching: Introducing switch expressions in Java 17 significantly improves the language’s expressiveness. It allows developers to write more concise and error-resistant code. The pattern-matching feature for switch statements enables developers to write more flexible and readable code structures, particularly when dealing with complex data types.
  • Introduction of the InstantSource Interface: Java 17 introduces the InstantSource interface, enhancing handling time-sensitive operations. This interface allows abstracting the system clock, making it easier to test time-based code by manipulating the clock during testing. This is particularly useful for applications where time manipulation and testing against different time scenarios are crucial.

Garbage Collection Improvements

A critical aspect of the Java 8 vs Java 17 comparison lies in the garbage collection (GC) advancements.

Garbage collection is essential for efficient memory management, and the improvements from Java 8 to Java 17 are noteworthy.

  • Overview of GC Progress from JDK 8 to JDK 17: Java 17 has made significant strides in garbage collection, focusing on improving throughput, reducing latency, and optimizing memory usage. These improvements contribute to a more efficient and robust Java runtime capable of easily handling large-scale and complex applications.
  • Differences in GC Approaches and Performance:
    • G1 Garbage Collector: Java 17 continues enhancing the G1 GC, which is designed for applications requiring large heaps with minimal GC latency. G1 GC offers a predictable garbage collection pattern and improved performance over the older collectors.
    • Z Garbage Collector (ZGC): Introduced in later versions and matured by Java 17, ZGC is a scalable, low-latency collector. It’s designed to handle multi-terabyte heaps with minimal impact on application latency.
    • Improvements in Parallel GC: The Parallel GC, often suitable for high-throughput applications, has also seen enhancements. It’s optimized for environments where maximizing the overall throughput is the primary goal, making it ideal for backend processing applications.
    • Impact on Performance: The advancements in GC technology in Java 17 have improved application performance, especially in high-demand, low-latency environments. The diversity in GC options allows developers to choose the most suitable collector based on their application’s specific needs, whether handling large data sets, ensuring consistent response times, or optimizing throughput.

In summary, Java 17’s new features and GC improvements represent a significant leap forward from Java 8, offering developers powerful tools and capabilities to build modern, efficient, and robust applications.

Performance Enhancements

In Java 8 vs Java 17, a significant area of interest is the performance enhancements each version offers.

Java 17, the recent release, has introduced several optimizations, making it a compelling choice for developers focused on building high-performance applications.

  • Comparison of Performance and Optimization Between Java 8 and Java 17:
    • Java 8: Introduced features like lambda expressions and stream API, substantially improving coding efficiency and readability. However, Java 8’s performance was primarily optimized for the hardware and software environments of its time.
    • Java 17: Leaps forward in performance optimization. This version has many improvements that cater to modern hardware capabilities, providing better usage of system resources. Java 17’s JIT compiler, for instance, has been enhanced to generate more efficient machine code, leading to faster application performance.
  • Improvements in Areas Like Throughput, Latency, and Memory Footprint:
    • Throughput: Java 17 has shown marked improvements in throughput, especially in applications involving heavy computational tasks. Enhanced JIT compilation and optimizations in the garbage collection mechanism contribute to this increased throughput.
    • Latency: One of the critical areas where Java 17 excels over Java 8 is in reduced latency. Introducing low-pause garbage collectors like ZGC and improvements in the G1 collector mean that Java 17 can handle large heaps with significantly lower pause times.
    • Memory Footprint: Java 17 also brings optimizations in memory management. Features like the compact string representation and improvements in data-class handling reduce the overall memory footprint of applications, making them more efficient in resource-constrained environments.

Migration Considerations

Migrating from Java 8 to Java 17 is a decision that involves weighing the challenges against the potential benefits. It’s a step that can significantly impact the performance and scalability of applications but also comes with its set of considerations.

  • Challenges and Benefits of Migrating from Java 8 to Java 17:
    • Challenges: Migrating to Java 17 can be challenging, especially for large and complex applications. The migration process might require code refactoring to adapt to new language features and APIs. Additionally, compatibility issues with third-party libraries and tools might arise, requiring thorough testing and validation.
    • Benefits: The benefits of migrating to Java 17 are substantial. Enhanced performance, improved security features, access to modern APIs, and the promise of long-term support make Java 17 an attractive proposition for future-proofing applications.
  • Critical Considerations for Developers and Organizations:
    • Assessment of Existing Codebase: It’s crucial to assess the existing codebase for compatibility with Java 17. This includes evaluating the use of deprecated APIs and features in Java 8 that might not be supported in Java 17.
    • Performance Testing: Before migration, it’s advisable to perform thorough performance testing to understand the impact of the new version on existing applications.
    • Training and Skill Upgradation: Developers need to be trained in the new features and best practices associated with Java 17 to leverage its full potential.
    • Plan for Gradual Migration: A gradual migration strategy is often more manageable for large projects. This approach allows for addressing issues incrementally and reduces the risk of significant disruptions.

In conclusion, the migration from Java 8 to Java 17 presents opportunities for significant performance improvements and access to cutting-edge features. However, it requires careful planning and consideration to ensure a smooth transition.

Best Practices for Java Developers

In the realm of Java 8 vs Java 17, adopting best practices is pivotal for developers aiming to fully leverage the capabilities of Java 17. These practices not only help in harnessing the new features effectively but also contribute to writing high-performing and maintainable code.

  • Effective Use of New Java 17 Features:
    • Embrace Sealed Classes and Interfaces: Utilize sealed classes and interfaces to enforce stricter type hierarchies, leading to more maintainable and error-resistant code.
    • Leverage Enhanced instanceOf: Adopt the enhanced instanceOf operator to simplify type checking and casting, reducing boilerplate code.
    • Implement Switch Expressions Effectively: Use switch expressions for more readable and concise code, particularly when handling multiple conditions.
    • Optimize with InstantSource Interface: Employ the InstantSource interface for better handling and testing of time-based operations.
  • Optimizing Code for Performance and Maintainability:
    • Utilize Modern Garbage Collectors: Choose the appropriate garbage collector based on application needs. For instance, use ZGC for applications requiring low latency.
    • Adopt Modularization: Embrace the modularization features introduced in Java 9 for better project organization and easier dependency management.
    • Refactor Legacy Code: Gradually refactor legacy Java 8 code to use the more efficient features and APIs available in Java 17.
    • Continuous Performance Monitoring: Regularly monitor and optimize the performance of applications, especially when upgrading Java versions or implementing new features.


  • What are the major differences between Java 8 and Java 17? Java 17 introduces several new features like sealed classes, pattern matching for switch statements, and enhanced garbage collection mechanisms, which are not present in Java 8.
  • Is it worth upgrading from Java 8 to Java 17? Upgrading to Java 17 is beneficial for accessing the latest features, performance improvements, and better long-term support, especially for enterprise-level applications.
  • Are there any compatibility issues when migrating from Java 8 to Java 17? Compatibility issues can arise, particularly with third-party libraries and APIs that may not have been updated for Java 17. Thorough testing and gradual migration are recommended.
  • Can Java 8 code run on Java 17 without modifications? In most cases, Java 8 code can run on Java 17, but updating the code to take advantage of the latest features and performance improvements is advisable.


Reflecting on the journey from Java 8 to Java 17, we observe a substantial evolution in Java’s capabilities.

Java 17 brings forward a range of advancements that enhance the programming experience, offering improved performance, better code maintainability, and more robust features.


  • Fredrik Filipsson

    Fredrik Filipsson brings two decades of Oracle license management experience, including a nine-year tenure at Oracle and 11 years in Oracle license consulting. His expertise extends across leading IT corporations like IBM, enriching his profile with a broad spectrum of software and cloud projects. Filipsson's proficiency encompasses IBM, SAP, Microsoft, and Salesforce platforms, alongside significant involvement in Microsoft Copilot and AI initiatives, enhancing organizational efficiency.