Integrated Development Environment (IDE) is a comprehensive software platform that wraps tasks like code development, building, debugging, and testing within a single application or framework. Some popular graphical IDEs include Visual Studio, Eclipse, IntelliJ IDEA, NetBeans, and Xcode. Some popular text-based IDEs include Vim, Emacs, Sublime text, and Nano.
Table of contents
IDEs offer a unified graphical user interface with tightly integrated components. Developers can compile, build, deploy, and run programs; and manage dependencies, plugins, and project files within a single window. Features like auto-code completion, unit testing, and code suggestions speed up development tasks by handling syntax and build issues, allowing developers to focus on core business logic.
Most of the high-level programming languages have an IDE. For instance, Eclipse is a multi-language IDE that supports Java, JavaScript, HTML, and many more languages using plugins.
Here is an example screenshot of Eclipse:
Eclipse IDE screenshot displaying main features of the IDE
Integrated Development Environment comprises essential components that facilitate an "integrated" development process and eliminate the need for switching between multiple applications to perform the basic development tasks.
Main features and working of IDE
To use an IDE (excluding cloud-based IDE), install the compatible version for your operating system. IDE provides a programming experience like a regular text editor and also handles compilation, execution, testing, project management, and version control seamlessly within its unified environment.
You can also choose your own themes and colors for syntax errors and highlighting. Note that a GUI (graphical user interface) or CLI (command line interface) source code editor, like notepad++ and Vim, also provides this functionality. However, they still lack the power of other features — like code refactoring, autocompletion, and indexing — that IDE text editors have. These features improve developer productivity and speed up the software development process.
An IDE eliminates the need to manually call the compiler for every code change. Without an IDE, you would have to execute compiler commands specific to the language for code compilation. The IDE automates the build process and program execution, displaying the output in a console.
Similarly, for interpreted languages like Python, an IDE eliminates the need to run the code in a separate shell or terminal. As code complexity grows, executing code outside an IDE becomes challenging.
You can set up debug points or breakpoints in your IDE for examining the code. During execution, the built-in debugger pauses the execution at each breakpoint one by one, and the developer can run and examine the code line by line. This eases the work of software developers and lets them find the hardest of bugs in the software code.
IDEs also help running automated tests using a testing framework like JUnit, pytest, or PHPUnit.
Next, let’s talk about the main ingredients of an IDE.
The code editor is where you type your program code. The IDE provides syntax highlighting, where the keywords and errors are shown in a different color and font for easy identification. In the below screenshot, the code editor is at the center where we can write all the code.
Code editor displaying a small Java program on Eclipse IDE
Note the color coding in the text editor. The keywords are in orange, the system and custom classes are in blue, variable names are in yellow, and so on. This makes the code more readable and easy to debug.
A lexical analyzer takes code character by character and converts it into a sequence of tokens. The tokens are then sent to the syntax analyzer to evaluate the correctness. The lexical analyzer sends only those characters that are part of the actual code — for instance, keywords like void, return; identifiers like variable name; operators and separators.
The first stage of compilation i.e. lexical analysis or scanning
The syntax analyzer receives tokens from lexical analyzer and checks if the received input is in correct syntax. It builds a parse tree or a syntax tree, using the predefined grammatical rules of the language, and reports any syntax errors in the code. Look at the below example, where the keyword “public” is spelled incorrectly. The syntax checker gives instant feedback:
After syntax analysis, the tokens are passed to the semantic analyzer, which analyzes semantic errors including type checking, flow control checking, and label checking. Examples include usage of the same variable name in the same scope, using undeclared variables, and assigning the wrong type to a variable.
A semantic error caught by the Integrated Development Environment semantic analyzer looks like this:
Once the developer addresses errors identified by the lexical, syntax, and semantic analyzers, the compiler generates machine-independent intermediate code, which is then transformed into object code. The compiler checks for all errors in the source code simultaneously.
The compiler shows all the errors simultaneously before the program is executed
The compiler also looks for optimizations in the code, indicated as a warning — for example, eliminating unused variables and combining similar code snippets. After optimization, the compiler converts the intermediate (object) code into the machine code for the specific target machine.
Example showing the warning given by compiler for unused variable
Some languages use interpreters instead of a compiler. Interpreters execute the code line by line and do not convert the source code into machine code. Any error in one line of the source code has to be corrected for the interpreter to move to the next line. Languages like PHP and Perl use an interpreter.
Below is an example of a Jupyter Notebook IDE that has a built-in interpreter:
Interpreter checks for errors line by line during execution
Using an in-built debugger allows developers to run code line by line, facilitating error detection and troubleshooting. A debugger indicates the specific line where code execution fails, such as when encountering a null value causing a failed dot operation, as in the screenshot below.
Debugger stopping at a line causing the program error
IDEs also offer plugin support, allowing you to import or add plugins from a URL or your local system. Popular plugins include GitToolBox, translate, Maven helper, and Rainbow brackets. Additionally, IDEs often offer features like context-based intelligent code completion, refactoring support, best practices suggestions, code search, test case, and build automation tools. Some modern IDEs even support visual programming, such as Scratch programming language, where code elements can be dragged and dropped in a graphical interface.
Our earlier examples with Eclipse IDE demonstrated its use as a desktop-based Java development IDE. You can use Eclipse for other programming languages like C and Python using plugins, which means Eclipse is also a multi-language IDE. Similarly, various IDEs fall into different categories, including:
Multi-language IDEs support coding in multiple programming languages. Visual Studio is a good example of a multiple language IDE that supports about 36 different languages. It consists of a suite of installers for various languages, including optional plug-ins and packages. NetBeans, IntelliJ IDEA, and Eclipse are popular IDEs that support multiple languages.
Cloud IDEs can be accessed via a browser. Other than being platform-independent, they do not consume your system space and computational resources, as nothing needs to be installed. It is also easy to collaborate and share the project with others. Some examples are CodePen (for HTML, CSS, and JavaScript), and Jupyter (Python). Repl.it is a cloud-based multi-language Integrated Development Environment that supports languages like Python, Node.js, Java, and C.
Mobile IDEs like Android Studio and Xcode specifically cater to mobile development. Apart from the basic IDE features, these IDEs include an emulator that allows developers to simulate mobile applications across multiple devices. Some IDEs like Visual Studio provide cross-platform mobile development support out-of-the-box.
Language-specific IDEs function with a single language. These IDEs are good for projects or organizations that work with only one programming language. By using a language specific IDE, developers can add specialized features and development tools that help in faster application or web development. Some popular ones are C-free for C/C++ and RubyMine for Ruby/Rails.
By integrating development tools into a single screen, IDEs eliminate the need for separate applications. They are beneficial for beginners to learn and explore coding, enabling project development without initial setup or integrations. IDEs provide a great platform for developers to expand their skill set. To reiterate, here are the most important benefits of an IDE:
IDEs offer unparalleled capabilities for projects with extensive codebases, setting them apart from plain text editors. Lightweight desktop versions (like Atom, Visual Studio Code) and cloud-based IDEs eliminate the space and resource consumption issues. Choosing an IDE empowers developers, novice or experienced, to optimize their code for enhanced efficiency and expedite software development.
No. Notepad++ is a source code editor with rich IDE-like features, like syntax highlighting, file version comparison, and search/replace functionality. Its capabilities can be enhanced using plugins. However, it does not come under the category of an IDE.