{"id":36170,"date":"2024-11-26T14:01:36","date_gmt":"2024-11-26T06:01:36","guid":{"rendered":"https:\/\/fwq.ai\/blog\/36170\/"},"modified":"2024-11-26T14:01:36","modified_gmt":"2024-11-26T06:01:36","slug":"%e5%a6%82%e4%bd%95%e4%bd%bf%e7%94%a8-java-%e5%b0%86%e6%95%b0%e6%8d%ae%e8%a1%8c%e5%bd%a2%e5%bc%8f%e8%bd%ac%e6%8d%a2%e4%b8%ba%e6%8c%89%e7%8f%ad%e7%ba%a7%e5%92%8c%e5%ad%a6%e7%94%9f-id-%e5%88%86%e7%bb%84","status":"publish","type":"post","link":"https:\/\/fwq.ai\/blog\/36170\/","title":{"rendered":"\u5982\u4f55\u4f7f\u7528 Java \u5c06\u6570\u636e\u884c\u5f62\u5f0f\u8f6c\u6362\u4e3a\u6309\u73ed\u7ea7\u548c\u5b66\u751f ID \u5206\u7ec4\u7684\u5217\u5f62\u5f0f\uff1f"},"content":{"rendered":"

\"\u5982\u4f55\u4f7f\u7528<\/p>\n

java \u4e2d\u5c06\u6570\u636e\u884c\u5f62\u5f0f\u8f6c\u6362\u4e3a\u5217\u5f62\u5f0f<\/strong><\/p>\n

\u7ed9\u5b9a\u4e00\u4e2a\u5305\u542b\u73ed\u7ea7\u3001\u5b66\u751fid\u3001\u79d1\u76ee\u548c\u5206\u6570\u7684\u6570\u636e\u96c6\uff0c\u8981\u6c42\u5c06\u5176\u8f6c\u6362\u4e3a\u6309\u73ed\u7ea7\u548c\u5b66\u751fid\u5206\u7ec4\uff0c\u79d1\u76ee\u548c\u5206\u6570\u4f5c\u4e3a\u5217\u7684\u5f62\u5f0f\u3002<\/p>\n

\u8981\u5b9e\u73b0\u6b64\u8f6c\u6362\uff0c\u53ef\u4ee5\u4f7f\u7528 java \u7684 stream\u3001collect \u548c groupingby \u64cd\u4f5c\uff1a<\/p>\n

\/\/ \u6e90\u6570\u636e\nList<Record> records = ...\n\n\/\/ \u6309\u73ed\u7ea7\u548c\u5b66\u751f ID \u5206\u7ec4\nMap<String, Map<Integer, List<Record>>> groupedRecords =\n    records.stream()\n        .collect(groupingBy(Record::getClass, groupingBy(Record::getStudentId)));\n\n\/\/ \u521b\u5efa\u7ed3\u679c\u5217\u8868\nList<Result> results = new ArrayList<>();\n\n\/\/ \u904d\u5386\u5206\u7ec4\u540e\u7684\u6570\u636e\uff0c\u6784\u5efa\u7ed3\u679c\nfor (Map.Entry<String, Map<Integer, List<Record>>> classEntry : groupedRecords.entrySet()) {\n    for (Map.Entry<Integer, List<Record>> studentEntry : classEntry.getValue().entrySet()) {\n        Result result = new Result();\n        result.setClass(classEntry.getKey());\n        result.setStudentId(studentEntry.getKey());\n\n        \/\/ \u586b\u5145\u79d1\u76ee\u548c\u5206\u6570\n        for (Record record : studentEntry.getValue()) {\n            switch (record.getSubject()) {\n                case \"English\":\n                    result.setEnglish(record.getScore());\n                    break;\n                case \"Math\":\n                    result.setMath(record.getScore());\n                    break;\n                case \"PE\":\n                    result.setPe(record.getScore());\n                    break;\n            }\n        }\n\n        \/\/ \u6dfb\u52a0\u5230\u7ed3\u679c\u5217\u8868\n        results.add(result);\n    }\n}<\/pre>\n
 \u767b\u5f55\u540e\u590d\u5236 <\/p>\n
\u6700\u7ec8\uff0cresults \u5217\u8868\u5c06\u5305\u542b\u6309\u73ed\u7ea7\u548c\u5b66\u751fid\u5206\u7ec4\u7684\u8bb0\u5f55\uff0c\u79d1\u76ee\u548c\u5206\u6570\u4f5c\u4e3a\u5217\u5f62\u5f0f\u5c55\u793a\u3002<\/p>\n
\u7acb\u5373\u5b66\u4e60<\/span>\u201c\u201d\uff1b<\/p>\n
\u4ee5\u4e0a\u5c31\u662f\u5982\u4f55\u4f7f\u7528 Java \u5c06\u6570\u636e\u884c\u5f62\u5f0f\u8f6c\u6362\u4e3a\u6309\u73ed\u7ea7\u548c\u5b66\u751f ID \u5206\u7ec4\u7684\u5217\u5f62\u5f0f\uff1f\u7684\u8be6\u7ec6\u5185\u5bb9\uff0c\u66f4\u591a\u8bf7\u5173\u6ce8\u7c73\u4e91\u5176\u5b83\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"
java \u4e2d\u5c06\u6570\u636e\u884c\u5f62\u5f0f\u8f6c\u6362\u4e3a\u5217\u5f62\u5f0f \u7ed9\u5b9a\u4e00\u4e2a\u5305\u542b\u73ed\u7ea7\u3001\u5b66\u751fid\u3001\u79d1\u76ee\u548c\u5206\u6570\u7684\u6570\u636e\u96c6\uff0c\u8981\u6c42\u5c06\u5176\u8f6c\u6362\u4e3a\u6309\u73ed\u7ea7\u548c\u5b66\u751fid\u5206\u7ec4\uff0c\u79d1\u76ee\u548c\u5206\u6570\u4f5c\u4e3a\u5217\u7684\u5f62\u5f0f\u3002 \u8981\u5b9e\u73b0\u6b64\u8f6c\u6362\uff0c\u53ef\u4ee5\u4f7f\u7528 java \u7684 stream\u3001collect \u548c groupingby \u64cd\u4f5c\uff1a \/\/ \u6e90\u6570\u636e List<Record> records = … \/\/ \u6309\u73ed\u7ea7\u548c\u5b66\u751f ID \u5206\u7ec4 Map<String, Map<Integer, List<Record>>> groupedRecords = records.stream() .collect(groupingBy(Record::getClass, groupingBy(Record::getStudentId))); \/\/ \u521b\u5efa\u7ed3\u679c\u5217\u8868 List<Result> results = new ArrayList<>(); \/\/ \u904d\u5386\u5206\u7ec4\u540e\u7684\u6570\u636e\uff0c\u6784\u5efa\u7ed3\u679c for (Map.Entry<String, Map<Integer, List<Record>>> classEntry : groupedRecords.entrySet()) { for (Map.Entry<Integer, List<Record>> studentEntry : classEntry.getValue().entrySet()) { Result result = […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[16],"tags":[],"class_list":["post-36170","post","type-post","status-publish","format-standard","hentry","category-16"],"_links":{"self":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/36170","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/comments?post=36170"}],"version-history":[{"count":0,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/posts\/36170\/revisions"}],"wp:attachment":[{"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/media?parent=36170"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/categories?post=36170"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fwq.ai\/blog\/wp-json\/wp\/v2\/tags?post=36170"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}