code: private void init() {
  		this.paused = false;
  		this.stopped = true;
  		this.tasksDoneCount = 0;
  		this.tasksTotalCount = 0;
  		this.initialized = false;
  
  		// Add a default fetch filter and any custom ones
  		defaultFetchFilter = new DefaultFetchFilter();
  		this.addFetchFilter(defaultFetchFilter);
  		
  		for (FetchFilter filter : extension.getCustomFetchFilters()) {
  			this.addFetchFilter(filter);
  		}
  
  		// Add a default parse filter and any custom ones
  		this.addParseFilter(new DefaultParseFilter(spiderParam, extension.getMessages()));
  		for (ParseFilter filter : extension.getCustomParseFilters())
  			this.addParseFilter(filter);
  		
  		// Add the scan context, if any
  		defaultFetchFilter.setScanContext(this.scanContext);
  		defaultFetchFilter.setDomainsAlwaysInScope(spiderParam.getDomainsAlwaysInScopeEnabled());
  
  	}
docs: Initialize the spider.