Strategy design pattern with Java

Algorithm.java

public interface Algorithm {

	void execute();

}

AlgorithmA.java

public class AlgorithmA implements Algorithm {

	@Override
	public void execute() {
		System.out.println("doing great in A");
	}

}

AlgorithmB.java

public class AlgorithmB implements Algorithm {

	@Override
	public void execute() {
		System.out.println("B is doing great");
	}

}

StrategyContext.java

public class StrategyContext {

	private Algorithm algorithm;

	public StrategyContext(Algorithm algorithm) {
		this.algorithm = algorithm;
	}

	public void doIt() {
		this.algorithm.execute();
	}

	public void setAlgorithm(Algorithm algorithm) {
		this.algorithm = algorithm;
	}

}

StrategyDemo.java

public class StrategyDemo {

	public static void main(String[] args) {
		Algorithm algorithmA = new AlgorithmA();
		Algorithm algorithmB = new AlgorithmB();
		
		StrategyContext strategyContext = new StrategyContext(algorithmA);
		
		strategyContext.doIt();
		
		strategyContext.setAlgorithm(algorithmB);
		
		strategyContext.doIt();
	}

}