Contexts and Dependency Injection (CDI) is a Jakarta specification that defines how a container creates and manages application objects, resolves their dependencies, and provides related services such as lifecycle callbacks, events, and interceptors. It is more than field-injection annotations: the application declares what it needs, and a CDI-capable container supplies a matching bean and manages it according to its scope.
The current final specification is CDI 5.0, released August 20, 2026. It requires Java SE 17 or later. Jakarta Contexts and Dependency Injection Specification 5.0
What is CDI in Java?
CDI stands for Contexts and Dependency Injection. In Jakarta applications, it is the standard contract for declaring application components, connecting their dependencies, and letting a container manage their creation and lifecycle. The specification describes portable behavior; the exact setup, packaging, and supported features depend on the runtime you choose.
The word “contexts” matters: CDI associates beans with lifecycles and contexts rather than treating every object as an unmanaged instance. A container can create and destroy beans, perform injection and lifecycle callbacks, resolve dependencies, deliver events, and apply interceptors. CDI Full also supports decorators. These capabilities work together around application objects; CDI is not just a shortcut for constructing objects.
Free tools Windows power users keep installed
One-click scans. No signup required.
#1 Best Overall
- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
- Compact & Travel-Friendly: The ultra-compact design allows the adapter to stay plugged into your device without blocking adjacent ports or adding bulk, reducing wear and tear on your original USB ports.
- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
How does CDI know which bean to inject?
CDI resolves an injection point from the bean’s types and qualifiers. Types establish what kind of dependency is being requested; qualifiers are annotation types that distinguish among otherwise suitable beans.
For example, an application could define a payment-service type and qualifiers such as @CardPayment and @BankTransfer. An injection point marked with @CardPayment can then distinguish the card implementation from the bank-transfer implementation. These names illustrate a possible application design; they are not built-in CDI payment features.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
This lets components depend on an appropriate abstraction instead of hard-coding how a dependency is constructed. The container must be able to identify a matching bean from the injection point’s type and qualifiers; ambiguous or unsatisfied dependencies need to be addressed in the application or runtime configuration.
What are CDI scopes?
Every bean has a scope. Scope governs the lifecycle of its instances and the contexts in which they are visible. Choose a scope that matches the state the object represents and how long that state should live. HTTP-related scopes rely on a web application environment; they do not automatically exist in every Java program.
Quick wins for a faster PC:
Repair Windows errors before they cause bigger problemsFix Now →Fix the driver behind crashes, sound loss and screen glitchesFind Drivers →Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
| Scope | Lifecycle and context |
|---|---|
| Request | Applies to one HTTP request. |
| Session | Spans a user’s HTTP requests. |
| Application | Shares state across the application’s users. |
| Dependent | The object has the lifecycle of the bean that uses it as a client. |
| Conversation | Can span multiple requests within boundaries controlled by the developer. |
These summaries follow the Jakarta EE Tutorial’s CDI introduction. Session and conversation scopes are CDI Full features, so check the feature set of the target runtime before relying on them.
What else does CDI do besides injection?
Producers
Producer methods and fields let an application control how an object is obtained while still making the resulting object available for injection. This is useful when construction involves logic or when an application needs to expose an object it does not instantiate through a typical bean constructor.
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
Interceptors
Interceptor bindings associate interception behavior with beans. They provide a way to apply behavior around invocations without putting that cross-cutting behavior directly into every business method.
Events
CDI events allow one component to notify interested components without directly depending on their implementations. That can reduce coupling between the component that raises an event and the components that observe it.
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
Decorators
CDI Full includes decorators, which add behavior around a bean while retaining its bean contract. CDI Lite does not include every advanced CDI Full capability.
The Jakarta CDI guide and the specification describe these features as part of CDI’s broader component model.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What is the difference between CDI Lite and CDI Full?
CDI 5.0 organizes the specification into CDI Lite, CDI Full, and Java SE parts. CDI Lite is a subset for more restricted environments; CDI Full adds advanced capabilities. In practical terms, the feature set matters when selecting a runtime: session and conversation scopes and decorators are Full features, so their availability cannot be assumed in a Lite-oriented environment.
The specification defines the portable contract, but it does not by itself tell you how to enable CDI in a particular server or which implementation-specific configuration to use. Verify runtime support and setup in the current documentation for the chosen implementation.
What changed in CDI 5.0?
The Jakarta CDI 5.0 specification is final and dated August 20, 2026. Its stated minimum Java version is Java SE 17. Those are specification-version facts, not a claim about a particular runtime’s release schedule or compatibility matrix. Consult the runtime’s own documentation for its supported CDI features and Java versions.
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
