{"id":61281,"date":"2024-10-13T09:56:16","date_gmt":"2024-10-13T01:56:16","guid":{"rendered":"https:\/\/server.hk\/cnblog\/61281\/"},"modified":"2024-10-13T09:56:16","modified_gmt":"2024-10-13T01:56:16","slug":"el%e8%a1%a8%e9%81%94%e5%bc%8f%e5%af%a6%e7%8f%be%e6%95%b8%e6%93%9a%e5%ba%ab%e5%9c%96%e7%89%87%e8%bc%b8%e5%87%ba-el-%e8%aa%bf%e6%95%b8%e6%93%9a%e5%ba%ab%e8%bc%b8%e5%87%ba%e5%9c%96%e7%89%87","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/61281\/","title":{"rendered":"EL\u8868\u9054\u5f0f\u5be6\u73fe\u6578\u64da\u5eab\u5716\u7247\u8f38\u51fa (el \u8abf\u6578\u64da\u5eab\u8f38\u51fa\u5716\u7247)"},"content":{"rendered":"

EL\u8868\u9054\u5f0f\u5be6\u73fe\u6578\u64da\u5eab\u5716\u7247\u8f38\u51fa<\/h1>\n

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EL\u8868\u9054\u5f0f\u662f\u4e00\u7a2e\u7528\u65bc\u7c21\u5316Java EE\u61c9\u7528\u7a0b\u5e8f\u4e2d\u6578\u64da\u8a2a\u554f\u7684\u8a9e\u8a00\u3002\u5b83\u5141\u8a31\u958b\u767c\u8005\u5728JSP\uff08JavaServer Pages\uff09\u4e2d\u8f15\u9b06\u5730\u8a2a\u554fJava\u5c0d\u8c61\u7684\u5c6c\u6027\u3002EL\u8868\u9054\u5f0f\u7684\u8a9e\u6cd5\u7c21\u55ae\uff0c\u901a\u5e38\u4ee5${}\u7684\u5f62\u5f0f\u51fa\u73fe\uff0c\u9019\u4f7f\u5f97\u5728\u9801\u9762\u4e2d\u5d4c\u5165Java\u4ee3\u78bc\u8b8a\u5f97\u66f4\u52a0\u76f4\u89c0\u3002<\/p>\n

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\nCREATE TABLE images (\n    id INT PRIMARY KEY AUTO_INCREMENT,\n    name VARCHAR(255),\n    image BLOB\n);\n<\/code><\/pre>\n
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\nimport java.sql.*;\nimport java.io.*;\n\npublic class ImageRetriever {\n    public static byte[] getImage(int id) {\n        byte[] imageBytes = null;\n        try {\n            Connection conn = DriverManager.getConnection(\"jdbc:mysql:\/\/localhost:3306\/yourdb\", \"username\", \"password\");\n            PreparedStatement stmt = conn.prepareStatement(\"SELECT image FROM images WHERE id = ?\");\n            stmt.setInt(1, id);\n            ResultSet rs = stmt.executeQuery();\n            if (rs.next()) {\n                imageBytes = rs.getBytes(\"image\");\n            }\n            conn.close();\n        } catch (SQLException e) {\n            e.printStackTrace();\n        }\n        return imageBytes;\n    }\n}\n<\/code><\/pre>\n
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\n\n\n\n\n\n\n<\/code><\/pre>\n
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