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Usage

@TempDir with JimfsTempDirFactory

The simplest way to use Jimfs JUnit Jupiter is to set the factory attribute of @TempDir to JimfsTempDirFactory:

import io.github.scordio.jimfs.junit.jupiter.JimfsTempDirFactory;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.io.TempDir;

@Test
void test(@TempDir(factory = JimfsTempDirFactory.class) Path tempDir) {
    assertEquals("jimfs", tempDir.getFileSystem().provider().getScheme());
}

tempDir is resolved to an in-memory temporary directory based on Jimfs, configured appropriately for the current platform.

While the example shows the injection of the temporary directory into a test method parameter, the same can also be done with class fields and constructor parameters.

@JimfsTempDir

@JimfsTempDir is an annotation that can be used as a drop-in replacement for @TempDir(factory = JimfsTempDirFactory.class):

import io.github.scordio.jimfs.junit.jupiter.JimfsTempDir;
import org.junit.jupiter.api.Test;

@Test
void test(@JimfsTempDir Path tempDir) {
    assertEquals("jimfs", tempDir.getFileSystem().provider().getScheme());
}

The default behavior of the annotation is equivalent to using JimfsTempDirFactory directly: tempDir is resolved to an in-memory temporary directory based on Jimfs, configured appropriately for the current platform.

For better control over the underlying in-memory file system, @JimfsTempDir offers an optional value attribute that can be set to the desired configuration, one of:

  • DEFAULT: based on the corresponding configuration parameter (default)
  • FOR_CURRENT_PLATFORM: appropriate to the current platform
  • OS_X: for a Mac OS X-like file system
  • UNIX: for a UNIX-like file system
  • WINDOWS: for a Windows-like file system

For example, the following defines a Windows-like temporary directory, regardless of the platform on which the test is running:

import io.github.scordio.jimfs.junit.jupiter.JimfsTempDir;
import org.junit.jupiter.api.Test;

import static io.github.scordio.jimfs.junit.jupiter.JimfsTempDir.Configuration.WINDOWS;

@Test
void test(@JimfsTempDir(WINDOWS) Path tempDir) {
    assertEquals("\\", tempDir.getFileSystem().getSeparator());
}