Thank you for your contribution!

What is your use case for this operation? Why you need to delete a protected file with H2?

I just run test org.h2.test.store.TestMVStore on Windows, and it failed with exception AccessDeniedException

And Exception stack is shown as follows

Exception in thread "main" org.h2.message.DbException: Cannot delete file "./data/test/TestMVStore" [90025-219] at org.h2.message.DbException.get(DbException.java:212) at org.h2.store.fs.disk.FilePathDisk.delete(FilePathDisk.java:209) at org.h2.store.fs.FileUtils.delete(FileUtils.java:109) at org.h2.test.store.TestMVStore.testCompactFully(TestMVStore.java:470) at org.h2.test.store.TestMVStore.test(TestMVStore.java:71) at org.h2.test.TestBase.testFromMain(TestBase.java:477) at org.h2.test.store.TestMVStore.main(TestMVStore.java:50) Caused by: org.h2.jdbc.JdbcSQLNonTransientException: Cannot delete file "./data/test/TestMVStore" [90025-219] at org.h2.message.DbException.getJdbcSQLException(DbException.java:554) at org.h2.message.DbException.getJdbcSQLException(DbException.java:477) ... 7 more Caused by: java.nio.file.AccessDeniedException: .\data\test\TestMVStore at sun.nio.fs.WindowsException.translateToIOException(WindowsException.java:83) at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:97) at sun.nio.fs.WindowsException.rethrowAsIOException(WindowsException.java:102) at sun.nio.fs.WindowsFileSystemProvider.implDelete(WindowsFileSystemProvider.java:269) at sun.nio.fs.AbstractFileSystemProvider.deleteIfExists(AbstractFileSystemProvider.java:108) at java.nio.file.Files.deleteIfExists(Files.java:1165) at org.h2.store.fs.disk.FilePathDisk.delete(FilePathDisk.java:200) ... 5 more

I do not think it's such a good idea. RO flag exist for a reason, and if user decide to remove file, there are tools to do so.
What if user has no permissions to remove file (unix), what if it is a directory, what if ...
On the other hand, test need to be fixed.

I do not think it's such a good idea. RO flag exist for a reason, and if user decide to remove file, there are tools to do so. What if user has no permissions to remove file (unix), what if it is a directory, what if ... On the other hand, test need to be fixed.

So only delete file on Windows file systems with AccessDeniedException.

@andreitokar
Internal file system API of H2 is designed in that way:

And it doesn't provide any way to reset this flag back.

Actually I don't see how it can be reset on POSIX systems, we don't preserve original access permissions on them anywhere.

H2 can set RO flag only on Windows. This flag also prevents deletion on this system.

On POSIX systems H2 removes write permissions from owner, group and others instead (ACLs, if any, aren't touched). It doesn't prevent file deletion, H2 was always able to remove read-only files on them.

I think older versions of H2 were able to delete read-only files on Windows too, because legacy File.delete() calls removeFileOrDirectory() in WinNTFileSystem_md.c and it resets attributes back to normal before deletion, but I don't have a Windows system to test it.

New versions of H2 use NIO.2 API and this API throws an AccessDeniedException instead.

So this PR is expected to restore consistent behavior of old version of H2.

If we don't like it, we can add a new setWriteable() to FilePath and call in everywhere. But CI tests are run only on Linux, so unnoticed regressions are possible.

H2 can set RO flag

If that's the case, and it was a regression, then I take it back, sorry for the noise.