implemented issue #25553(Optimize single character equality checks)

[abhishek-abhi]

No description provided.

[abhishek-abhi]

Hi, @snicoll , please review my PR. This time I worked on one raised issue #25553.

[snicoll]

@abhishek-abhi thanks for the PR. Please don't mention individual team member, the team already receives a notification when the PR is created.

[sbrannen]

Thanks for the PR. We are happy to see that you are eager to contribute.

Please note that you actually implemented changes for #25552 and not for #25553.

In addition, both of those issues have descriptions stating "Investigate claims made in Micro optimizations in Java. String.equals() article."

That means that the issues are there as placeholders for the core team to investigate.

If the core team wishes for someone from the community to pick up an issue, we add the status: ideal-for-contribution label.

If you don't see the status: ideal-for-contribution label on an issue, you should post a comment asking the team if a contribution is welcome before submitting a PR.

In addition, some of the changes in this PR are breaking changes that would result in a NullPointerException.

Regarding the tests, if we go to the trouble of updating tests like that we would typically rather refactor the assertions to make use of dedicated AssertJ functionality that better suits the purpose.

In light of the above, I am closing this PR, and the team will investigate #25552 and #25553 in the 5.3 RC1 time frame.

[sbrannen]

For future reference, please make sure that you run a full build locally before submitting any PR.

This PR actually fails the build due to a compilation error:

> Task :spring-core:compileJava FAILED
/source/spring-framework/spring-core/src/main/java/org/springframework/util/StringUtils.java:97: error: cannot find symbol
                return (str == null || str.isEmpty());
                                          ^
  symbol:   method isEmpty()
  location: variable str of type Object
1 error

FAILURE: Build failed with an exception.

If that error is fixed, there are still 3 additional compilation errors:

> Task :spring-messaging:compileJava
/source/spring-framework/spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/reactive/AbstractNamedValueMethodArgumentResolver.java:105: error: cannot find symbol
                else if (arg.isEmpty() && namedValueInfo.defaultValue != null) {
                            ^
  symbol:   method isEmpty()
  location: variable arg of type Object
/source/spring-framework/spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/support/AbstractNamedValueMethodArgumentResolver.java:113: error: cannot find symbol
                else if (arg.isEmpty() && namedValueInfo.defaultValue != null) {
                            ^
  symbol:   method isEmpty()
  location: variable arg of type Object
2 errors

> Task :spring-messaging:compileJava FAILED

> Task :spring-web:compileJava
/source/spring-framework/spring-web/src/main/java/org/springframework/web/method/annotation/AbstractNamedValueMethodArgumentResolver.java:118: error: cannot find symbol
                else if (arg.isEmpty() && namedValueInfo.defaultValue != null) {
                            ^
  symbol:   method isEmpty()
  location: variable arg of type Object
1 error

> Task :spring-web:compileJava FAILED

[abhishek-abhi]

I will fix these and reopen the PR

[sbrannen]

I will fix these and reopen the PR

There is no need to do that.

I have added the status: pending-design-work label to both of those issues and have assigned them to myself for the time being.

[abhishek-abhi]

I will fix these and reopen the PR

There is no need to do that.

I have added the status: pending-design-work label to both of those issues and have assigned them to myself for the time being.

Okay. Can you please assign this to myself if possible. I would love to work on this issue.