{"id":11388,"date":"2024-03-14T14:01:45","date_gmt":"2024-03-14T14:01:45","guid":{"rendered":"https:\/\/www.silicloud.com\/blog\/how-can-java-generate-unique-random-numbers\/"},"modified":"2025-08-04T11:17:22","modified_gmt":"2025-08-04T11:17:22","slug":"how-can-java-generate-unique-random-numbers","status":"publish","type":"post","link":"https:\/\/www.silicloud.com\/blog\/how-can-java-generate-unique-random-numbers\/","title":{"rendered":"Java Unique Random Numbers Guide"},"content":{"rendered":"<p>In Java, you can generate unique random numbers by using the Random class and Set collection. Here is an example code:<\/p>\n<pre class=\"post-pre\"><code><span class=\"hljs-keyword\">import<\/span> java.util.Random;\r\n<span class=\"hljs-keyword\">import<\/span> java.util.Set;\r\n<span class=\"hljs-keyword\">import<\/span> java.util.HashSet;\r\n\r\n<span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">class<\/span> <span class=\"hljs-title class_\">RandomNumberGenerator<\/span> {\r\n\r\n    <span class=\"hljs-keyword\">public<\/span> <span class=\"hljs-keyword\">static<\/span> <span class=\"hljs-keyword\">void<\/span> <span class=\"hljs-title function_\">main<\/span><span class=\"hljs-params\">(String[] args)<\/span> {\r\n        Set&lt;Integer&gt; set = <span class=\"hljs-keyword\">new<\/span> <span class=\"hljs-title class_\">HashSet<\/span>&lt;&gt;();\r\n        <span class=\"hljs-type\">Random<\/span> <span class=\"hljs-variable\">random<\/span> <span class=\"hljs-operator\">=<\/span> <span class=\"hljs-keyword\">new<\/span> <span class=\"hljs-title class_\">Random<\/span>();\r\n        \r\n        <span class=\"hljs-keyword\">while<\/span> (set.size() &lt; <span class=\"hljs-number\">10<\/span>) {\r\n            <span class=\"hljs-type\">int<\/span> <span class=\"hljs-variable\">randomNumber<\/span> <span class=\"hljs-operator\">=<\/span> random.nextInt(<span class=\"hljs-number\">100<\/span>); <span class=\"hljs-comment\">\/\/ \u751f\u62100\u523099\u4e4b\u95f4\u7684\u968f\u673a\u6570<\/span>\r\n            set.add(randomNumber);\r\n        }\r\n        \r\n        <span class=\"hljs-keyword\">for<\/span> (<span class=\"hljs-type\">int<\/span> num : set) {\r\n            System.out.println(num);\r\n        }\r\n    }\r\n}\r\n<\/code><\/pre>\n<p>In the example code above, a HashSet collection is first created to store the generated random numbers. Then, the Random class is used to generate random numbers and add them to the collection. The generation of random numbers stops when the number of elements in the collection equals the desired number of unique random numbers to be generated. Finally, the collection is traversed and the unique random numbers are printed out.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In Java, you can generate unique random numbers by using the Random class and Set collection. Here is an example code: import java.util.Random; import java.util.Set; import java.util.HashSet; public class RandomNumberGenerator { public static void main(String[] args) { Set&lt;Integer&gt; set = new HashSet&lt;&gt;(); Random random = new Random(); while (set.size() &lt; 10) { int randomNumber = [&hellip;]<\/p>\n","protected":false},"author":11,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_import_markdown_pro_load_document_selector":0,"_import_markdown_pro_submit_text_textarea":"","footnotes":""},"categories":[1],"tags":[3459,578,7142,799,14685],"class_list":["post-11388","post","type-post","status-publish","format-standard","hentry","category-uncategorized","tag-hashset","tag-java-collections","tag-java-random","tag-programming-tutorial","tag-unique-numbers"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v21.5 (Yoast SEO v21.5) - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>Java Unique Random Numbers Guide - 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