java/Project/command/RetryCommand.java

package command;

import model.CrawlResult;
import exception.CrawlerException;
import view.CrawlerView;

import java.util.List;

public class RetryCommand implements Command {
    private final Command originalCommand;
    private final int maxRetries;
    private final CrawlerView view;

    public RetryCommand(Command originalCommand, int maxRetries, CrawlerView view) {
        this.originalCommand = originalCommand;
        this.maxRetries = maxRetries;
        this.view = view;
    }

    @Override
    public List<CrawlResult> execute() throws CrawlerException {
        CrawlerException lastException = null;

        for (int attempt = 1; attempt <= maxRetries; attempt++) {
            try {
                view.showMessage("执行命令: " + originalCommand.getName() 
                        + " (尝试 " + attempt + "/" + maxRetries + ")");
                return originalCommand.execute();
            } catch (CrawlerException e) {
                lastException = e;
                view.showError("命令执行失败: " + e.getMessage());

                if (attempt < maxRetries) {
                    view.showMessage("等待重试...");
                    try {
                        Thread.sleep(1000 * attempt);
                    } catch (InterruptedException ie) {
                        Thread.currentThread().interrupt();
                        break;
                    }
                }
            }
        }

        view.showError("命令执行失败，已达到最大重试次数 " + maxRetries);
        throw lastException;
    }

    @Override
    public String getName() {
        return "Retry[" + originalCommand.getName() + "]";
    }
}