{"id":1790,"date":"2022-11-26T22:31:46","date_gmt":"2022-11-26T14:31:46","guid":{"rendered":"https:\/\/qaqaq.top\/?p=1790"},"modified":"2022-11-27T12:40:30","modified_gmt":"2022-11-27T04:40:30","slug":"preparedstatement%e8%a7%a3%e5%86%b3sql%e6%b3%a8%e5%85%a5%e9%97%ae%e9%a2%98","status":"publish","type":"post","link":"https:\/\/qaqaq.top\/?p=1790","title":{"rendered":"PreparedStatement\u89e3\u51b3SQL\u6ce8\u5165\u95ee\u9898"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code>package top.qaqaq.P23.statement.crud;\r\n\r\nimport java.lang.reflect.Field;\r\nimport java.sql.Connection;\r\nimport java.sql.PreparedStatement;\r\nimport java.sql.ResultSet;\r\nimport java.sql.ResultSetMetaData;\r\nimport java.util.Scanner;\r\n\r\nimport org.junit.Test;\r\n\r\nimport top.qaqaq.P12.statement.crud.User;\r\nimport top.qaqaq.P14.util.JDBCUtils;\r\n\r\n\/**\r\n * \r\n * @Description \u6f14\u793a\u4f7f\u7528PreparedStatement\u66ff\u6362Statement\uff0c\u89e3\u51b3SQL\u6ce8\u5165\u95ee\u9898\r\n * @author RichieZhang Email:18358892@qq.com\r\n * @version\r\n * @date 2022\u5e7411\u670826\u65e5\u4e0b\u53489:29:01\r\n *\r\n *\/\r\npublic class PreparedStatementTest {\r\n\r\n\t@Test\r\n\tpublic void testLogin() {\r\n\t\tScanner scanner = new Scanner(System.in);\r\n\t\t\r\n\t\tSystem.out.print(\"\u8bf7\u8f93\u5165\u7528\u6237\u540d\uff1a\");\r\n\t\tString user = scanner.nextLine();\r\n\t\tSystem.out.print(\"\u8bf7\u8f93\u5165\u5bc6\u7801\uff1a\");\r\n\t\tString password = scanner.next();\r\n\t\t\/\/SELECT user,password FROM user_table WHERE user = '1' or ' AND password = '=1 or '1' = '1'\r\n\t\tString sql = \"SELECT user,password FROM user_table WHERE user = ? AND password = ?\";\r\n\t\tUser returnUser = getInstance(User.class, sql, user, password);\r\n\t\tif(returnUser != null) {\r\n\t\t\tSystem.out.println(\"\u767b\u9646\u6210\u529f\");\r\n\t\t}else {\r\n\t\t\tSystem.out.println(\"\u7528\u6237\u540d\u4e0d\u5b58\u5728\u6216\u5bc6\u7801\u9519\u8bef\");\r\n\t\t}\r\n\t\t\r\n\t}\r\n\t\r\n\t\/**\r\n\t * \r\n\t * @Description\r\n\t * @author RichieZhang \u9488\u5bf9\u4e8e\u4e0d\u540c\u7684\u8868\u7684\u901a\u7528\u7684\u67e5\u8be2\u64cd\u4f5c\uff0c\u8fd4\u56de\u8868\u4e2d\u7684\u4e00\u6761\u8bb0\u5f55\r\n\t * @date 2022\u5e7411\u670826\u65e5\u4e0b\u53489:04:58\r\n\t * @param &lt;T>\r\n\t * @param clazz\r\n\t * @param sql\r\n\t * @param args\r\n\t * @return\r\n\t *\/\r\n\tpublic &lt;T> T getInstance(Class&lt;T> clazz, String sql, Object... args) {\r\n\t\tConnection conn = null;\r\n\t\tPreparedStatement ps = null;\r\n\t\tResultSet rs = null;\r\n\t\ttry {\r\n\t\t\tconn = JDBCUtils.getConnection();\r\n\r\n\t\t\tps = conn.prepareStatement(sql);\r\n\t\t\tfor (int i = 0; i &lt; args.length; i++) {\r\n\t\t\t\tps.setObject(i + 1, args&#91;i]);\r\n\t\t\t}\r\n\r\n\t\t\trs = ps.executeQuery();\r\n\t\t\t\/\/ \u83b7\u53d6\u7ed3\u679c\u96c6\u7684\u5143\u6570\u636e : ResultSetMetaData\r\n\t\t\tResultSetMetaData rsmd = rs.getMetaData();\r\n\t\t\t\/\/ \u901a\u8fc7ResultSetMetaData\u83b7\u53d6\u7ed3\u679c\u96c6\u4e2d\u7684\u5217\u6570\r\n\t\t\tint columnCount = rsmd.getColumnCount();\r\n\r\n\t\t\tif (rs.next()) {\r\n\t\t\t\tT t = clazz.newInstance();\r\n\t\t\t\t\/\/ \u5904\u7406\u7ed3\u679c\u96c6\u4e00\u884c\u6570\u636e\u4e2d\u7684\u6bcf\u4e00\u4e2a\u5217\r\n\t\t\t\tfor (int i = 0; i &lt; columnCount; i++) {\r\n\t\t\t\t\t\/\/ \u83b7\u53d6\u5217\u503c\r\n\t\t\t\t\tObject columnvalue = rs.getObject(i + 1);\r\n\r\n\t\t\t\t\t\/\/ \u83b7\u53d6\u6bcf\u4e2a\u5217\u7684\u5217\u540d\r\n\/\/\t\t\t\t\tString columnName = rsmd.getColumnName(i + 1);\r\n\t\t\t\t\tString columnLabel = rsmd.getColumnLabel(i + 1);\r\n\r\n\t\t\t\t\t\/\/ \u7ed9t\u5bf9\u8c61\u6307\u5b9a\u7684columnName\u5c5e\u6027\uff0c\u8d4b\u503c\u4e3acolumnvalue\uff1b\u901a\u8fc7\u53cd\u5c04\r\n\t\t\t\t\tField field = clazz.getDeclaredField(columnLabel);\r\n\t\t\t\t\tfield.setAccessible(true);\r\n\t\t\t\t\tfield.set(t, columnvalue);\r\n\r\n\t\t\t\t}\r\n\t\t\t\treturn t;\r\n\t\t\t}\r\n\t\t} catch (Exception e) {\r\n\t\t\te.printStackTrace();\r\n\t\t} finally {\r\n\t\t\tJDBCUtils.closeResource(conn, ps, rs);\r\n\t\t}\r\n\r\n\t\treturn null;\r\n\t}\r\n\r\n}\r\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[38],"tags":[48],"class_list":["post-1790","post","type-post","status-publish","format-standard","hentry","category-jdbc-code","tag-jdbc"],"_links":{"self":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1790"}],"collection":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1790"}],"version-history":[{"count":1,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1790\/revisions"}],"predecessor-version":[{"id":1791,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/1790\/revisions\/1791"}],"wp:attachment":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1790"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1790"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}