20 lines
739 B
Java
20 lines
739 B
Java
package singleton;
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public class Main {
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public static void main(String[] args) {
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System.out.println("=== Singleton Pattern Demo ===\n");
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DatabaseConnection c1 = DatabaseConnection.getInstance();
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DatabaseConnection c2 = DatabaseConnection.getInstance();
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DatabaseConnection c3 = DatabaseConnection.getInstance();
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System.out.println("\nAll three references same instance? " + (c1 == c2 && c2 == c3));
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System.out.println(c1.executeQuery("SELECT * FROM users"));
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System.out.println(c2.executeQuery("SELECT * FROM orders"));
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System.out.println(c3.executeQuery("SELECT COUNT(*) FROM products"));
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System.out.println("\nTotal queries: " + c1.getQueryCount());
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}
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}
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