{"id":62441,"date":"2024-10-13T19:00:15","date_gmt":"2024-10-13T11:00:15","guid":{"rendered":"https:\/\/server.hk\/cnblog\/62441\/"},"modified":"2024-10-13T19:00:15","modified_gmt":"2024-10-13T11:00:15","slug":"java%e6%87%89%e7%94%a8%e7%a8%8b%e5%ba%8f%e5%a6%82%e4%bd%95%e9%a9%97%e8%ad%89%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e9%87%8d%e8%a4%87%e6%80%a7%ef%bc%9f-java%e9%a9%97%e8%ad%89%e6%95%b8%e6%93%9a%e5%ba%ab","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/62441\/","title":{"rendered":"Java\u61c9\u7528\u7a0b\u5e8f\u5982\u4f55\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\uff1f (java\u9a57\u8b49\u6578\u64da\u5eab\u91cd\u8907\u6027)"},"content":{"rendered":"<h1 id=\"java%e6%87%89%e7%94%a8%e7%a8%8b%e5%ba%8f%e5%a6%82%e4%bd%95%e9%a9%97%e8%ad%89%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e9%87%8d%e8%a4%87%e6%80%a7%ef%bc%9f-PgnQnyWsPb\">Java\u61c9\u7528\u7a0b\u5e8f\u5982\u4f55\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\uff1f<\/h1>\n<p>\u5728\u958b\u767cJava\u61c9\u7528\u7a0b\u5e8f\u6642\uff0c\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\u9a57\u8b49\u662f\u4e00\u500b\u91cd\u8981\u7684\u8003\u91cf\u3002\u91cd\u8907\u6578\u64da\u4e0d\u50c5\u6703\u5f71\u97ff\u6578\u64da\u7684\u5b8c\u6574\u6027\uff0c\u9084\u53ef\u80fd\u5c0e\u81f4\u61c9\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u4e0b\u964d\u3002\u56e0\u6b64\uff0c\u4e86\u89e3\u5982\u4f55\u5728Java\u4e2d\u6709\u6548\u5730\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\u662f\u81f3\u95dc\u91cd\u8981\u7684\u3002<\/p>\n<h2 id=\"%e7%82%ba%e4%bb%80%e9%ba%bc%e9%9c%80%e8%a6%81%e9%a9%97%e8%ad%89%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e9%87%8d%e8%a4%87%e6%80%a7%ef%bc%9f-PgnQnyWsPb\">\u70ba\u4ec0\u9ebc\u9700\u8981\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\uff1f<\/h2>\n<p>\u6578\u64da\u5eab\u4e2d\u7684\u91cd\u8907\u6578\u64da\u53ef\u80fd\u6703\u5c0e\u81f4\u591a\u7a2e\u554f\u984c\uff0c\u5305\u62ec\uff1a<\/p>\n<ul>\n<li>\u6578\u64da\u4e0d\u4e00\u81f4\u6027\uff1a\u91cd\u8907\u6578\u64da\u53ef\u80fd\u5c0e\u81f4\u4e0d\u540c\u7684\u6578\u64da\u4f86\u6e90\u7522\u751f\u77db\u76fe\u3002<\/li>\n<li>\u6027\u80fd\u554f\u984c\uff1a\u67e5\u8a62\u91cd\u8907\u6578\u64da\u6703\u589e\u52a0\u6578\u64da\u5eab\u7684\u8ca0\u64d4\uff0c\u5f71\u97ff\u67e5\u8a62\u901f\u5ea6\u3002<\/li>\n<li>\u696d\u52d9\u908f\u8f2f\u932f\u8aa4\uff1a\u5728\u67d0\u4e9b\u60c5\u6cc1\u4e0b\uff0c\u91cd\u8907\u6578\u64da\u53ef\u80fd\u6703\u5c0e\u81f4\u696d\u52d9\u908f\u8f2f\u7684\u932f\u8aa4\u57f7\u884c\u3002<\/li>\n<\/ul>\n<h2 id=\"%e5%a6%82%e4%bd%95%e5%9c%a8java%e4%b8%ad%e9%a9%97%e8%ad%89%e6%95%b8%e6%93%9a%e5%ba%ab%e7%9a%84%e9%87%8d%e8%a4%87%e6%80%a7-PgnQnyWsPb\">\u5982\u4f55\u5728Java\u4e2d\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027<\/h2>\n<p>\u5728Java\u4e2d\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\u901a\u5e38\u6d89\u53ca\u4ee5\u4e0b\u5e7e\u500b\u6b65\u9a5f\uff1a<\/p>\n<h3 id=\"1-%e8%a8%ad%e8%a8%88%e6%95%b8%e6%93%9a%e5%ba%ab%e7%b5%90%e6%a7%8b-PgnQnyWsPb\">1. \u8a2d\u8a08\u6578\u64da\u5eab\u7d50\u69cb<\/h3>\n<p>\u9996\u5148\uff0c\u8a2d\u8a08\u6578\u64da\u5eab\u6642\u61c9\u8003\u616e\u5230\u91cd\u8907\u6027\u554f\u984c\u3002\u53ef\u4ee5\u901a\u904e\u8a2d\u7f6e\u552f\u4e00\u7d22\u5f15\u4f86\u9632\u6b62\u91cd\u8907\u6578\u64da\u7684\u63d2\u5165\u3002\u4f8b\u5982\uff0c\u5728MySQL\u4e2d\uff0c\u53ef\u4ee5\u9019\u6a23\u8a2d\u7f6e\uff1a<\/p>\n<pre><code>CREATE TABLE users (\n    id INT AUTO_INCREMENT PRIMARY KEY,\n    email VARCHAR(255) UNIQUE NOT NULL\n);<\/code><\/pre>\n<h3 id=\"2-%e4%bd%bf%e7%94%a8sql%e6%9f%a5%e8%a9%a2%e6%aa%a2%e6%9f%a5%e9%87%8d%e8%a4%87%e6%80%a7-PgnQnyWsPb\">2. \u4f7f\u7528SQL\u67e5\u8a62\u6aa2\u67e5\u91cd\u8907\u6027<\/h3>\n<p>\u5728\u63d2\u5165\u65b0\u6578\u64da\u4e4b\u524d\uff0c\u53ef\u4ee5\u4f7f\u7528SQL\u67e5\u8a62\u4f86\u6aa2\u67e5\u662f\u5426\u5df2\u5b58\u5728\u76f8\u540c\u7684\u6578\u64da\u3002\u4f8b\u5982\uff0c\u6aa2\u67e5\u96fb\u5b50\u90f5\u4ef6\u662f\u5426\u5df2\u5b58\u5728\uff1a<\/p>\n<pre><code>SELECT COUNT(*) FROM users WHERE email = ?;<\/code><\/pre>\n<p>\u5982\u679c\u8fd4\u56de\u7684\u8a08\u6578\u5927\u65bc0\uff0c\u5247\u8868\u793a\u8a72\u96fb\u5b50\u90f5\u4ef6\u5df2\u5b58\u5728\u3002<\/p>\n<h3 id=\"3-%e5%9c%a8java%e4%b8%ad%e5%af%a6%e7%8f%be%e9%87%8d%e8%a4%87%e6%80%a7%e9%a9%97%e8%ad%89-PgnQnyWsPb\">3. \u5728Java\u4e2d\u5be6\u73fe\u91cd\u8907\u6027\u9a57\u8b49<\/h3>\n<p>\u4ee5\u4e0b\u662f\u4e00\u500b\u7c21\u55ae\u7684Java\u793a\u4f8b\uff0c\u5c55\u793a\u5982\u4f55\u5728\u63d2\u5165\u6578\u64da\u4e4b\u524d\u6aa2\u67e5\u91cd\u8907\u6027\uff1a<\/p>\n<pre><code>import java.sql.Connection;\nimport java.sql.DriverManager;\nimport java.sql.PreparedStatement;\nimport java.sql.ResultSet;\n\npublic class UserRegistration {\n    private static final String DB_URL = \"jdbc:mysql:\/\/localhost:3306\/yourdatabase\";\n    private static final String USER = \"username\";\n    private static final String PASS = \"password\";\n\n    public boolean isEmailExists(String email) {\n        String query = \"SELECT COUNT(*) FROM users WHERE email = ?\";\n        try (Connection conn = DriverManager.getConnection(DB_URL, USER, PASS);\n             PreparedStatement pstmt = conn.prepareStatement(query)) {\n            pstmt.setString(1, email);\n            ResultSet rs = pstmt.executeQuery();\n            if (rs.next()) {\n                return rs.getInt(1) &gt; 0;\n            }\n        } catch (Exception e) {\n            e.printStackTrace();\n        }\n        return false;\n    }\n\n    public void registerUser(String email) {\n        if (isEmailExists(email)) {\n            System.out.println(\"\u8a72\u96fb\u5b50\u90f5\u4ef6\u5df2\u5b58\u5728\uff01\");\n        } else {\n            \/\/ \u63d2\u5165\u65b0\u7528\u6236\u7684\u4ee3\u78bc\n            System.out.println(\"\u7528\u6236\u8a3b\u518a\u6210\u529f\uff01\");\n        }\n    }\n}\n<\/code><\/pre>\n<h3 id=\"4-%e4%bd%bf%e7%94%a8%e4%ba%8b%e5%8b%99%e8%99%95%e7%90%86-PgnQnyWsPb\">4. \u4f7f\u7528\u4e8b\u52d9\u8655\u7406<\/h3>\n<p>\u5728\u9032\u884c\u6578\u64da\u63d2\u5165\u6642\uff0c\u4f7f\u7528\u4e8b\u52d9\u53ef\u4ee5\u78ba\u4fdd\u6578\u64da\u7684\u4e00\u81f4\u6027\u3002\u5982\u679c\u63d2\u5165\u904e\u7a0b\u4e2d\u767c\u751f\u932f\u8aa4\uff0c\u53ef\u4ee5\u56de\u6efe\u4e8b\u52d9\uff0c\u907f\u514d\u6578\u64da\u4e0d\u4e00\u81f4\u7684\u60c5\u6cc1\u3002<\/p>\n<pre><code>try {\n    conn.setAutoCommit(false);\n    \/\/ \u63d2\u5165\u6578\u64da\u7684\u4ee3\u78bc\n    conn.commit();\n} catch (SQLException e) {\n    conn.rollback();\n    e.printStackTrace();\n} finally {\n    conn.setAutoCommit(true);\n}<\/code><\/pre>\n<h2 id=\"%e7%b8%bd%e7%b5%90-PgnQnyWsPb\">\u7e3d\u7d50<\/h2>\n<p>\u5728Java\u61c9\u7528\u7a0b\u5e8f\u4e2d\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\u662f\u4e00\u500b\u91cd\u8981\u7684\u6b65\u9a5f\uff0c\u80fd\u5920\u6709\u6548\u5730\u63d0\u9ad8\u6578\u64da\u7684\u5b8c\u6574\u6027\u548c\u61c9\u7528\u7a0b\u5e8f\u7684\u6027\u80fd\u3002\u901a\u904e\u8a2d\u8a08\u5408\u7406\u7684\u6578\u64da\u5eab\u7d50\u69cb\u3001\u4f7f\u7528SQL\u67e5\u8a62\u6aa2\u67e5\u91cd\u8907\u6027\u3001\u5728Java\u4e2d\u5be6\u73fe\u9a57\u8b49\u908f\u8f2f\u4ee5\u53ca\u4f7f\u7528\u4e8b\u52d9\u8655\u7406\uff0c\u53ef\u4ee5\u6709\u6548\u5730\u9632\u6b62\u91cd\u8907\u6578\u64da\u7684\u63d2\u5165\u3002<\/p>\n<p>\u5982\u679c\u60a8\u6b63\u5728\u5c0b\u627e\u9ad8\u6548\u7684 <a href=\"https:\/\/server.hk\">VPS<\/a> \u89e3\u6c7a\u65b9\u6848\u4f86\u652f\u6301\u60a8\u7684Java\u61c9\u7528\u7a0b\u5e8f\uff0cServer.HK\u63d0\u4f9b\u7a69\u5b9a\u7684 <a href=\"https:\/\/server.hk\">\u9999\u6e2fVPS<\/a> \u670d\u52d9\uff0c\u5e6b\u52a9\u60a8\u8f15\u9b06\u7ba1\u7406\u6578\u64da\u5eab\u548c\u61c9\u7528\u7a0b\u5e8f\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u4e86\u89e3\u5982\u4f55\u5728Java\u61c9\u7528\u7a0b\u5e8f\u4e2d\u9a57\u8b49\u6578\u64da\u5eab\u7684\u91cd\u8907\u6027\uff0c\u78ba\u4fdd\u6578\u64da\u7684\u552f\u4e00\u6027\u548c\u5b8c\u6574\u6027\uff0c\u63d0\u5347\u61c9\u7528\u6027\u80fd\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-62441","post","type-post","status-publish","format-standard","hentry","category-database"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/62441","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=62441"}],"version-history":[{"count":1,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/62441\/revisions"}],"predecessor-version":[{"id":62442,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/62441\/revisions\/62442"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=62441"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=62441"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=62441"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}