How to Manage Multiple API Versions Within a Single Java Source File?

What are the best practices for managing different API versions in the same Java source file?

Managing multiple API versions within a single Java source file can enhance maintainability and reduce code duplication. Here are strategies and best practices to consider when implementing this approach.

public interface ApiVersion { public void execute(); }
class ApiV1 implements ApiVersion { public void execute() { /* V1 Logic */ }}
class ApiV2 implements ApiVersion { public void execute() { /* V2 Logic */ }}
public class ApiHandler { public void handleRequest(String version) { ApiVersion api;
if(version.equals("v1")) { api = new ApiV1(); }
else { api = new ApiV2(); }
api.execute(); }}

Causes

• Overlapping functionalities between different versions of an API.
• The requirement to maintain backwards compatibility for existing clients.

Solutions

• Use versioning in the URL or request headers to differentiate between API versions.
• Implement a versioning system in your code structure. For example, use separate classes or methods for each version.
• Ensure that shared functionalities are abstracted away into common utilities to avoid repetition.

Mistake: Not properly abstracting shared functionalities between versions.

Solution: Utilize base classes or interfaces to encapsulate shared properties and methods.

Mistake: Confusing version routing logic, making maintenance difficult.

Solution: Clearly define routing strategies for each version and keep your version control logic simple.