鍦↗ava涓紝鍙互閫氳繃浠ヤ笅姝ラ浣跨敤session.getAttribute()鏂规硶锛?/p>

1. 鑾峰彇HttpSession瀵硅薄锛氬湪Java Web搴旂敤绋嬪簭涓紝鍙互閫氳繃HttpServletRequest瀵硅薄鐨?code>getSession()鏂规硶鏉ヨ幏鍙?code>HttpSession瀵硅薄銆備緥濡傦細HttpSession session = request.getSession();

2. 浣跨敤getAttribute()鏂规硶鑾峰彇灞炴€у€硷細浣跨敤session.getAttribute("attributeName")鏂规硶鏉ヨ幏鍙栨寚瀹氬睘鎬у悕鐨勫睘鎬у€笺€傚叾涓紝attributeName鏄鑾峰彇鐨勫睘鎬у悕銆備緥濡傦細Object attributeValue = session.getAttribute("username");

3. 瀵瑰睘鎬у€艰繘琛岀被鍨嬭浆鎹細鐢变簬getAttribute()鏂规硶杩斿洖鐨勬槸涓€涓?code>Object绫诲瀷鐨勫璞★紝鍥犳濡傛灉闇€瑕佷娇鐢ㄥ叿浣撶被鍨嬬殑灞炴€у€硷紝闇€瑕佽繘琛岀被鍨嬭浆鎹€備緥濡傦細String username = (String) session.getAttribute("username");

娉ㄦ剰浜嬮」锛?/p>

• 鍦ㄤ娇鐢?code>getAttribute()鏂规硶鑾峰彇灞炴€у€间箣鍓嶏紝闇€瑕佺‘淇濆凡缁忛€氳繃setAttribute()鏂规硶灏嗗睘鎬у€艰缃埌HttpSession瀵硅薄涓€?/p>

• 濡傛灉鎸囧畾鐨勫睘鎬у悕涓嶅瓨鍦ㄦ垨鑰呭睘鎬у€间负null锛?code>getAttribute()鏂规硶灏嗚繑鍥?code>null銆?/p>

绀轰緥浠ｇ爜锛?/p>

HttpSession session = request.getSession();
String username = (String) session.getAttribute("username");
if (username != null) {
System.out.println("Username: " + username);
} else {
System.out.println("Username is not set.");
}