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java ( 2358842 ) - com.iluwatar.de ( 2361551 ) stack: com.iluwatar.dependency.injection.App.main(App.java:57) org.codehaus.mojo.exec.ExecJavaMojo.doMain(ExecJavaMojo.java:385) org.codehaus.mojo.exec.ExecJavaMojo.doExec(ExecJavaMojo.java:374) org.codehaus.mojo.exec.ExecJavaMojo.lambda$execute$0(ExecJavaMojo.java:296) java.base/java.lang.Thread.run(Thread.java:840)
/*
 * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
 *
 * The MIT License
 * Copyright © 2014-2022 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.dependency.injection;

import com.google.inject.Guice;

/**
 * Dependency Injection pattern deals with how objects handle their dependencies. The pattern
 * implements so-called inversion of control principle. Inversion of control has two specific rules:
 * - High-level modules should not depend on low-level modules. Both should depend on abstractions.
 * - Abstractions should not depend on details. Details should depend on abstractions.
 *
 * <p>In this example we show you three different wizards. The first one ({@link SimpleWizard}) is
 * a naive implementation violating the inversion of control principle. It depends directly on a
 * concrete implementation which cannot be changed.
 *
 * <p>The second and third wizards({@link AdvancedWizard} and {@link AdvancedSorceress}) are more
 * flexible. They do not depend on any concrete implementation but abstraction. They utilize
 * Dependency Injection pattern allowing their {@link Tobacco} dependency to be injected through
 * constructor ({@link AdvancedWizard}) or setter ({@link AdvancedSorceress}). This way, handling
 * the dependency is no longer the wizard's responsibility. It is resolved outside the wizard
 * class.
 *
 * <p>The fourth example takes the pattern a step further. It uses Guice framework for Dependency
 * Injection. {@link TobaccoModule} binds a concrete implementation to abstraction. Injector is then
 * used to create {@link GuiceWizard} object with correct dependencies.
 */
public class App {

  /**
   * Program entry point.
   *
   * @param args command line args
   */
  public static void main(String[] args) {
    var simpleWizard = new SimpleWizard();
    simpleWizard.smoke();

    var advancedWizard = new AdvancedWizard(new SecondBreakfastTobacco());
    advancedWizard.smoke();

    var advancedSorceress = new AdvancedSorceress();
    advancedSorceress.setTobacco(new SecondBreakfastTobacco());
    advancedSorceress.smoke();

    var injector = Guice.createInjector(new TobaccoModule());
    var guiceWizard = injector.getInstance(GuiceWizard.class);
    guiceWizard.smoke();
  }
}
Variables All
No.FromNameValue
157args[Ljava.lang.String;@2e8b42f9
END 0 00
Output All Filter Merge
Process FilterThread Filter
2358842 java 2361551 com.iluwatar.de
No.PNPIDTIDTNTLMessage
1java23588422361551com.iluwatar.decom.iluwatar.dependency.injection.TobaccoISimpleWizard smoking OldTobyTobacco
2java23588422361551com.iluwatar.decom.iluwatar.dependency.injection.TobaccoIAdvancedWizard smoking SecondBreakfastTobacco
3java23588422361551com.iluwatar.decom.iluwatar.dependency.injection.TobaccoIAdvancedSorceress smoking SecondBreakfastTobacco
4java23588422361551com.iluwatar.decom.iluwatar.dependency.injection.TobaccoIGuiceWizard smoking RivendellTobacco
END 0 0 0 0 0 00
Project:JavaDesignPatterns
Update:20240509
Commit:bf6456ba6
Source Code:dependency-injection
BuildTool:Java17
Compiler:Java17
Runtime:Openjdk17
System:MySystemD
Kernel:Linux5.10.211
Cpu:Intel:Corei7-7700K
Machine:AwesomeMachine