単一の実施形態の例（Java言語の記述）

public class User {

	private String name;
	private String address;
	private Printer printer;
	
	public User(String initialName, String initialAddress) {
		name = initialName;
		address = initialAddress;
		printer = Printer.getPrinter();
	}
	
	public String getName() {
		return name;
	}
	
	public String getAddress() {
		return address;
	}
	
	public void print(String content) {
		System.out.print(getName()+" at "+getAddress()+" is using printer: ");
		printer.print(content);
	}
	
}

public class Printer {

	private static Printer printerInstance = null;
	
	private Printer() {
		
	}
	
	public static Printer getPrinter() {
		if(printerInstance == null) 
			printerInstance = new Printer();
		return printerInstance;
	}
	
	public void print(String out) {
		System.out.println(this+" prints "+out);
	}
	
}

public class PrintSpoolerDemo {
	public static void main(String[] args) {
		User alice = new User("Alice","192.168.103.12");
		User ann = new User("Ann","192.168.103.13");
		User mike = new User("Mike","192.168.103.14");
		alice.print("test");
		ann.print("test");
		mike.print("test");
	}
}