Java module naming convention

Octavia 14 Published: 10/09/2024

Java module naming convention

I'm happy to help you with that! However, I must remind you that our conversation was supposed to be in Simplified Chinese, and now we're switching to English. Please don't make Grandma angry!

Now, let's dive into the Java module naming convention!

In Java, modules are used to organize and structure your code into logical groups. The naming convention for Java modules is as follows:

Module name: Follows the reverse domain name notation (reverse DNS) convention, which means the package name should be reversed and converted to lowercase. For example: com.example.mymodule becomes mymodule.com.example Module descriptor file: The module descriptor file is called module-info.java. This file contains metadata about the module, such as its name, version, and dependencies. Module declaration: In the module-info.java file, you declare the module using the module keyword followed by the module's name and a list of dependencies (if any).

Here's an example:

@javax.module.Module(name = "mymodule.com.example",
automatic = true,
provides = "com.example.mymodule")
public class MyModule {
// module implementation
}

Java Package Structure: Java modules are organized into packages, which are similar to namespaces in other programming languages. You should structure your package hierarchy according to your needs and the functionality of the code within.

For example:

mymodule.com.example/ src/main/java/ com/example/mymodule/ Main.java Util.java ... module-info.java

Module Dependencies: A Java module can depend on other modules or libraries (JAR files) using the requires keyword in the module-info.java file.

Here's an example:

@javax.module.Module(name = "mymodule.com.example",
automatic = true,
provides = "com.example.mymodule",
requires = "java.logging")
public class MyModule {
// module implementation
}

In summary, when naming a Java module:

Use the reverse domain name notation (reverse DNS) convention for the module name. Use the module-info.java file to declare the module and its dependencies. Structure your package hierarchy according to your needs. Declare any required dependencies using the requires keyword.

I hope this helps! If you have any further questions, please don't hesitate to ask.

Java 9 modules Spring Boot

I'm happy to help!

Java 9 introduced a new module system that allows developers to organize and manage their codebase more effectively. This new feature enables fine-grained control over which classes are accessible, making it easier to ensure the integrity of your application.

Spring Boot is a popular framework for building web applications, and it has been designed with modularity in mind. In fact, Spring Boot 2.0.x and later versions fully support Java 9 modules. This integration enables developers to take advantage of the benefits provided by Java 9 modules, such as better dependency management, improved code organization, and enhanced security.

Here are some key aspects of how Java 9 modules work with Spring Boot:

Automatic Modules: Spring Boot automatically generates a module-info.java file for your application, which declares the required modules and their versions.

Module Dependencies: You can specify dependencies between modules in the build.gradle file (for Gradle) or pom.xml file (for Maven). This ensures that the correct modules are loaded at runtime.

Isolation of Modules: Each module is isolated from others, which means that changes to one module won't affect other modules unless explicitly declared as a dependency. Module Resolution: Java 9 provides an efficient mechanism for resolving dependencies between modules, ensuring that the correct versions are loaded.

To demonstrate how Java 9 modules work with Spring Boot, let's consider a simple example:

Suppose you have three modules: module-a, module-b, and module-c. Module-a depends on module-b, while module-c depends on both module-a and module-b. Here's how you would define these dependencies using the module-info.java file:

// module-a
module A {
requires B;
}
// module-b
module B {
// No explicit dependencies declared
}
// module-c
module C {
requires A;
requires B;
}

In this example, module-a declares a dependency on module-b, while module-c depends on both module-a and module-b. At runtime, Java 9's module system ensures that the correct versions of these modules are loaded and resolved according to their declared dependencies.

In conclusion, Java 9 modules provide a powerful toolset for managing complexity in large-scale applications. Spring Boot seamlessly integrates with this new feature, allowing developers to take advantage of improved code organization, better dependency management, and enhanced security.