41 lines
1.2 KiB
Java
41 lines
1.2 KiB
Java
package command;
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/**
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* Command Design Pattern — Runnable Demo
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* Run: javac command/*.java -d out/command && java -cp out/command command.Main
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* Article: https://ankurm.com/command-design-pattern-java/
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*/
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public class Main {
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public static void main(String[] args) {
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System.out.println("=== Command Design Pattern Demo ===\n");
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TextEditor editor = new TextEditor();
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CommandHistory history = new CommandHistory();
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System.out.println("Initial: " + editor);
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history.execute(new InsertCommand(editor, "Hello", 0));
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System.out.println("After: " + editor);
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history.execute(new InsertCommand(editor, " World", 5));
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System.out.println("After: " + editor);
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history.execute(new DeleteCommand(editor, 5, 6));
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System.out.println("After: " + editor);
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System.out.println("\n-- Undo sequence --");
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history.undo();
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System.out.println("After undo: " + editor);
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history.undo();
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System.out.println("After undo: " + editor);
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history.undo();
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System.out.println("After undo: " + editor);
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history.undo(); // nothing left
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System.out.println("\n=== Demo complete ===");
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}
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}
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