--- title: What is double-check locking? - Cracking the Java Coding... description: Double-check locking is a pattern originally designed for lazy, thread-safe singleton initialization in Java. While it appears clever, it is error-prone and... canonical: https://daily.dev/posts/what-is-double-check-locking---cracking-the-java-coding-interview-javacoding-javatips-1ojs0nwyg twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: What is double-check locking? - Cracking the Java Coding Interview #javacoding #javatips | daily.dev og:description: Double-check locking is a pattern originally designed for lazy, thread-safe singleton initialization in Java. While it appears clever, it is error-prone and... og:url: https://daily.dev/posts/what-is-double-check-locking---cracking-the-java-coding-interview-javacoding-javatips-1ojs0nwyg og:image: https://api.daily.dev/og/posts/1OJS0NWYg.png og:image:alt: What is double-check locking? - Cracking the Java Coding Interview #javacoding #javatips og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # What is double-check locking? - Cracking the Java Coding Interview #javacoding #javatips **[Java \(Official Oracle\)](https://daily.dev/sources/java-oracle)** · 1 min read · 0 upvotes · 0 comments ## Summary Double-check locking is a pattern originally designed for lazy, thread-safe singleton initialization in Java. While it appears clever, it is error-prone and complex, requiring the field to be declared volatile to prevent race conditions. A simpler and more reliable alternative is using Java enums for singletons, as recommended by Effective Java, and used in the JDK itself (e.g., Comparator.naturalOrder()). ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: --- Tags: [#java](https://daily.dev/tags/java), [#design-patterns](https://daily.dev/tags/design-patterns) [View this post on daily.dev](https://daily.dev/posts/what-is-double-check-locking---cracking-the-java-coding-interview-javacoding-javatips-1ojs0nwyg) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"What is double-check locking? - Cracking the Java Coding Interview #javacoding #javatips","url":"https://daily.dev/posts/what-is-double-check-locking---cracking-the-java-coding-interview-javacoding-javatips-1ojs0nwyg","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/what-is-double-check-locking---cracking-the-java-coding-interview-javacoding-javatips-1ojs0nwyg"},"datePublished":"2026-03-16T08:13:24.248Z","dateModified":"2026-03-16T08:19:12.775Z","description":"Double-check locking is a pattern originally designed for lazy, thread-safe singleton initialization in Java. 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