crawler1.addUrl("https://site1.com");

Crawler crawler2 = container.getComponent("crawler");  
crawler2.setSessionId("session2");
crawler2.addUrl("https://site2.com");

// Execute concurrently
crawler1.setBackground(true);
crawler2.setBackground(true);

String sessionId1 = crawler1.execute();
String sessionId2 = crawler2.execute();

crawler1.awaitTermination();
crawler2.awaitTermination();
```

### Custom Interval Control

            file.delete();
            file.mkdirs();
            file.deleteOnExit();
            fileTransformer.setPath(file.getAbsolutePath());
            crawler.setBackground(true);
            ((UrlFilterImpl) crawler.urlFilter).setIncludeFilteringPattern("$1$2$3.*");
            crawler.addUrl(url);
            crawler.getCrawlerContext().setMaxAccessCount(maxCount);

            file.delete();
            file.mkdirs();
            file.deleteOnExit();
            fileTransformer.setPath(file.getAbsolutePath());
            crawler.setBackground(true);
            ((UrlFilterImpl) crawler.urlFilter).setIncludeFilteringPattern("$1$2$3.*");
            crawler.addUrl(url);
            crawler.getCrawlerContext().setMaxAccessCount(maxCount);

            file.mkdirs();
            file.deleteOnExit();
            fileTransformer.setPath(file.getAbsolutePath());

            final Crawler crawler1 = getComponent(Crawler.class);
            crawler1.setBackground(true);
            ((UrlFilterImpl) crawler1.urlFilter).setIncludeFilteringPattern("$1$2$3.*");
            crawler1.addUrl(url1);
            crawler1.getCrawlerContext().setMaxAccessCount(maxCount);

    /**
     * Sets the background mode for the crawler.
     * If true, the execute method will not wait for termination.
     * @param background true to run in background, false otherwise.
     */
    public void setBackground(final boolean background) {
        this.background = background;
    }

    /**
     * Checks if the crawler threads are daemon threads.
     * @return true if daemon threads, false otherwise.
     */