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DongHoon Lee
5c2ad14f50
ClassLoaderFilesResourcePatternResolver.isDeleted() calls resource.exists() and resource.getURI() inside the loop over the uploaded files, so both are repeated once per DELETED entry although neither depends on the entry. Every resource lookup made while the application context is being built goes through this method - about 1300 times per restart in the application I measured - so a session that has accumulated 100 deleted files performs around 130 000 file system lookups where 1300 are enough. This commit hoists both calls out of the loop: the resource is inspected at most once per call, on the first DELETED entry, and the URI comparison then uses the cached value. The method still returns on the first match and still reports a failing getURI() as an IllegalStateException, so behaviour is unchanged. The loop now walks the per-directory entry sets, which is what ClassLoaderFiles.addAll() and RestartServer already do, instead of the flattened view added in gh-46289. That view is wrapped in Collections.unmodifiableSet(), whose iterator is shared JDK code; in a running application its delegate calls are megamorphic and C2 stops inlining them, which made restarts with many accumulated files and no deletions slower than before gh-46289. isDeleted() returns a boolean, so the visiting order of the entries cannot change its result. Measured on a Spring Boot application driven through the remote restart path (restart request to ApplicationReadyEvent), 12 JVMs per variant and 20 restarts per JVM, medians: 100 source directories, 10 000 entries, 10 deleted: 278 ms -> 200 ms 100 source directories, 10 000 entries, 100 deleted: 891 ms -> 201 ms 100 source directories, 10 000 entries, 500 deleted: 3536 ms -> 200 ms 100 source directories, 50 000 entries, none deleted: 431 ms -> 341 ms 100 source directories, 10 000 entries, none deleted: 202 ms -> 192 ms no uploaded files: 150 ms -> 148 ms See gh-51841 Signed-off-by: DongHoon Lee <dhl1924@naver.com>
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:docs: https://docs.spring.io/spring-boot
:github: https://github.com/spring-projects/spring-boot
Spring Boot helps you to create Spring-powered, production-grade applications and services with absolute minimum fuss.
It takes an opinionated view of the Spring platform so that new and existing users can quickly get to the bits they need.
You can use Spring Boot to create stand-alone Java applications that can be started using `java -jar` or more traditional WAR deployments.
We also provide a command-line tool that runs Spring scripts.
Our primary goals are:
* Provide a radically faster and widely accessible getting started experience for all Spring development.
* Be opinionated, but get out of the way quickly as requirements start to diverge from the defaults.
* Provide a range of non-functional features common to large classes of projects (for example, embedded servers, security, metrics, health checks, externalized configuration).
* Absolutely no code generation and no requirement for XML configuration.
== Installation and Getting Started
The {docs}[reference documentation] includes detailed {docs}/installing.html[installation instructions] as well as a comprehensive {docs}/tutorial/first-application/index.html[``getting started``] guide.
Here is a quick teaser of a complete Spring Boot application in Java:
[source,java]
----
import org.springframework.boot.*;
import org.springframework.boot.autoconfigure.*;
import org.springframework.web.bind.annotation.*;
@RestController
@SpringBootApplication
public class Example {
@RequestMapping("/")
String home() {
return "Hello World!";
}
public static void main(String[] args) {
SpringApplication.run(Example.class, args);
}
}
----
== Getting Help
Are you having trouble with Spring Boot? We want to help!
* Check the {docs}/[reference documentation], especially the {docs}/how-to/index.html[How-to's] -- they provide solutions to the most common questions.
* Learn the Spring basics -- Spring Boot builds on many other Spring projects; check the https://spring.io[spring.io] website for a wealth of reference documentation.
If you are new to Spring, try one of the https://spring.io/guides[guides].
* If you are upgrading, read the {github}/wiki[release notes] for upgrade instructions and "new and noteworthy" features.
* Ask a question -- we monitor https://stackoverflow.com[stackoverflow.com] for questions tagged with https://stackoverflow.com/tags/spring-boot[`spring-boot`].
* Report bugs with Spring Boot at {github}/issues[github.com/spring-projects/spring-boot/issues].
== Contributing
We welcome contributions of all kinds!
Please read our link:CONTRIBUTING.adoc[contribution guidelines] before submitting a pull request.
== Reporting Issues
Spring Boot uses GitHub's integrated issue tracking system to record bugs and feature requests.
If you want to raise an issue, please follow the recommendations below:
* Before you log a bug, please search the {github}/issues[issue tracker] to see if someone has already reported the problem.
* If the issue doesn't already exist, {github}/issues/new[create a new issue].
* Please provide as much information as possible with the issue report.
We like to know the Spring Boot version, operating system, and JVM version you're using.
* If you need to paste code or include a stack trace, use Markdown.
+++```+++ escapes before and after your text.
* If possible, try to create a test case or project that replicates the problem and attach it to the issue.
== Building from Source
You don't need to build from source to use Spring Boot.
If you want to try out the latest and greatest, Spring Boot can be built and published to your local Maven cache using the https://docs.gradle.org/current/userguide/gradle_wrapper.html[Gradle wrapper].
You also need JDK 25.
[source,shell]
----
$ ./gradlew publishToMavenLocal
----
This command builds all modules and publishes them to your local Maven cache.
It won't run any of the tests.
If you want to build everything, use the `build` task:
[source,shell]
----
$ ./gradlew build
----
== Guides
The https://spring.io/[spring.io] site contains several guides that show how to use Spring Boot step-by-step:
* https://spring.io/guides/gs/spring-boot/[Building an Application with Spring Boot] is an introductory guide that shows you how to create an application, run it, and add some management services.
* https://spring.io/guides/gs/actuator-service/[Building a RESTful Web Service with Spring Boot Actuator] is a guide to creating a REST web service and also shows how the server can be configured.
== License
Spring Boot is Open Source software released under the https://www.apache.org/licenses/LICENSE-2.0.html[Apache 2.0 license].