An application development interface (API) is a computing interface that defines interactions between software. APIs allow developers to skip diving deeply in the source code of some third-party software. They simplify programming by abstracting the underlying implementation and only exposing objects or actions the developer needs. Thus developers don’t need to understand the file system operations occurring behind the scenes.
In Java development, most basic programming tasks are performed by the API’s classes and packages, which helps to minimize the number of lines written within one piece of code.
Java Development Kit (JDK) is comprised of three basic components, as follows:
- Java compiler;
- Java Virtual Machine (JVM);
- Java Application Programming Interface (API).
Java API describes the function of each of its components. Many of these components are pre-written and commonly used so developers can apply the pre-written code via the Java API. After referring to the available API classes and packages, developers can invoke the necessary code classes and packages for implementation.
Types of APIs
There are numerous kinds of APIs. There are about 15,000 publicly available APIs and many thousands of private APIs that companies use to expand their internal and external capabilities.
- Web APIs. Web APIs can be accessed using the HTTP protocol. They include the APIs used to communicate with the browser. They may be services such as web notifications and web storage.
- Public APIs. Public APIs are available to developers with minimal restrictions however they may require registration or the use of an API key. Many companies use public APIs from larger organizations like Facebook and Google to get access to data that would not be otherwise available.
- Internal APIs. Internal APIs can’t be accessed by external developers. They are used within a company and allow its developers to consume each other’s tools, data, and programs.
- Partner APIs. Partner APIs provide limited access that is controlled through a third-party API gateway. They are created for a particular purpose such as providing access to paid services.
- Composite APIs. Composite APIs provide access to several endpoints in one call. They are particularly useful in microservice architectures, where a user may need information from several services to perform a single task.
Why Do We Need API in Java?
Automation: With Java APIs, the work can be controlled by computer systems, programmers’ involvement is not required. Throughout APIs, software development companies can upgrade workflows to make them faster and more efficient.
Application: Since Java APIs can easily access the software components, there is much more flexibility in delivering data and services.
Efficiency: Once the access to a Java API is provided, the produced content can be released instantly and made available for each channel. This allows for quick content distribution.
Integration: Java APIs allow for easier content embedding. This ensures additional dynamic data delivery.
Actions You Can Take Through an API
There are four types of actions an API can take:
- GET requests data from a server;
- POST sends changes from the client to the server;
- PUT revises or adds to existing data;
- DELETE: deletes existing data.
When you combine the endpoints with these actions, you can search or update any available data over an API. These actions are all different and you will have to check the API documentation to learn how to code them.
These are the ways you can make a request on a server:
- HTTP: this is a really easy way to access data, but if you request a lot of data it won’t come back to you in a pretty format. It uses your internet browser as the client, and you get back a text document in coding language to sort through.
- Text formats: XML and JSON are the main languages for accessing data over an API. When you receive your data, you will need to wade through the XML or JSON code to understand what the server gave you.
Most APIs require an API key. Once you find an API you want to use, you will need to check out access requirements in the documentation. Then you will likely have to go through an identity verification. After that, you will get a unique string of letters and numbers to use when accessing the API.
The easiest way to start using an API is by finding an HTTP client online, like REST-Client, Paw or Postman. These tools can help you structure your requests with the API key you have for accessing existing APIs. You will still need knowledge of the documentation syntax, but there is very little coding knowledge required.
Another good way to get data from an API is to build a URL from existing API documentation. An API request doesn’t generally look that much different from a normal browser URL, but the returned data will be in a form that’s easy for computers to read.
An API is quite useful for pulling data from another app or software. If you know how to read the documentation and write the requests, you can get a large volume of data, but parsing all this data may be overwhelming. That’s where developers come into play. They can create programs that display data directly in a browser or an app in a format that is easy to understand.
This article barely describes the iceberg of the API technology. If you want to use APIs for your Java development project but don’t know how, our experienced team of Java developers can be of help. Feel free to contact us.