[Java] Dependency Injection

Dependency.java

/**
 * Dependency class for the Dependency Injection example.
 */
class Dependency {
  /**
   * The value enclosed inside this Dependency
   */
  private final Object value;
  
  /**
   * Single-parameter constructor accepting an Object as a value for this Dependency
   */
  public Dependency(Object value) {
    // Use explicit this inside a constructor to reference the field when the field and parameter are named the same.
    this.value = value;
  }
  
  /**
   * Returns the Object value stored in this Dependency
   */
  public Object getValue() { return value; }
}

DependencyInjection.java

/**
 * Entrypoint class for the Dependency Injection example.
 */
class DependencyInjection {
  /*
   * Entrypoint method for the Dependency Injection example.
   */
  public static void main(String[] args) {
     // Create a new 'Dependency' to be used by 'Dependent' classes
     // Dependency has a single parameter constructor for setting the enclosed value.
     final Dependency dependency = new Dependency("Hello, World!");
     // Create a new 'Dependent' using the created Dependency
     // Dependent has a single parameter constructor for setting the Dependency to execute.
     final Dependent dependent = new Dependent(dependency);
     // Execute the dependent class
     dependent.execute();

    // Standard output: 'Hello, World!'
  }
}

Dependent.java

/**
 * Dependent class for the Dependency Injection example.
 */
class Dependent {
  /**
   * The Dependency enclosed inside this Dependent
   */
  private final Dependency dependency;
  
  /**
   * Single-parameter constructor accepting a Dependency as a dependency for this Dependent
   */
  public Dependent(Dependency dependency) {
    // Use explicit this inside a constructor to reference the field when the field and parameter are named the same.
    this.dependency = dependency;
  }
  
  /**
   * Print the stored Dependency's 'getValue' output to the standard output.
   */
  public void execute() { 
    System.out.println(dependency.getValue());
  }
}