Close DeferredFileOutputStream to prevent FileNotFoundException on temp files (#157)

--------- Co-authored-by: copilot-swe-agent[bot] <[email protected]> Co-authored-by: slachiewicz <[email protected]>

Author: Copilot

src/main/java/org/codehaus/plexus/components/io/resources/Deferred.java

@@ -47,9 +47,10 @@ public Deferred(final PlexusIoResource resource, PlexusIoResourceCollection owne
  .get()
  : null;
 if (dfos != null){
-InputStreaminputStream = owner.getInputStream(resource);
-IOUtils.copy(inputStream, dfos);
-IOUtils.closeQuietly(inputStream);
+try (InputStreaminputStream = owner.getInputStream(resource);
+DeferredFileOutputStreamcloseable = dfos){
+IOUtils.copy(inputStream, dfos);
+ }
  }
  }
 

src/main/java/org/codehaus/plexus/components/io/resources/PlexusIoFileResource.java

@@ -108,11 +108,11 @@ private static DeferredFileOutputStream asDeferredStream(
  .setThreshold(5000000)
  .setPrefix("p-archiver")
  .get();
-InputStreaminputStream = supplier.getContents();
-InputStreamtransformed = transToUse.transform(resource, inputStream);
-IOUtils.copy(transformed, dfos);
-IOUtils.closeQuietly(inputStream);
-IOUtils.closeQuietly(transformed);
+try (InputStreaminputStream = supplier.getContents();
+InputStreamtransformed = transToUse.transform(resource, inputStream);
+DeferredFileOutputStreamcloseable = dfos){
+IOUtils.copy(transformed, dfos);
+}
 returndfos;
  }
 

src/test/java/org/codehaus/plexus/components/io/resources/PlexusIoFileResourceDeferredTest.java

@@ -0,0 +1,116 @@
+packageorg.codehaus.plexus.components.io.resources;
+
+importjava.io.File;
+importjava.io.IOException;
+importjava.io.InputStream;
+importjava.io.OutputStream;
+importjava.nio.charset.StandardCharsets;
+importjava.nio.file.Files;
+
+importorg.apache.commons.io.IOUtils;
+importorg.codehaus.plexus.components.io.attributes.FileAttributes;
+importorg.codehaus.plexus.components.io.functions.InputStreamTransformer;
+importorg.junit.jupiter.api.Test;
+importorg.junit.jupiter.api.io.TempDir;
+
+importstaticorg.junit.jupiter.api.Assertions.*;
+
+/**
+ * Tests for PlexusIoFileResource with DeferredFileOutputStream scenarios.
+ * This specifically tests the fix for issue #118 where temp files were deleted
+ * before they could be accessed, causing FileNotFoundException.
+ */
+publicclassPlexusIoFileResourceDeferredTest{
+
+@TempDir
+FiletempDir;
+
+@Test
+voidtestFileResourceWithTransformerCanReadContentsMultipleTimes() throwsIOException{
+// Create a test file with content larger than typical buffer size
+FiletestFile = newFile(tempDir, "test-file.txt");
+byte[] largeContent = newbyte[10000]; // 10KB
+for (inti = 0; i < largeContent.length; i++){
+largeContent[i] = (byte) ('A' + (i % 26));
+ }
+Files.write(testFile.toPath(), largeContent);
+
+// Create a transformer that modifies the content
+InputStreamTransformertransformer = (resource, inputStream) ->{
+// Simple transformer that reads and returns the same content
+returninputStream;
+ };
+
+// Create PlexusIoFileResource with transformer
+PlexusIoFileResourceresource =
+newPlexusIoFileResource(testFile, testFile.getName(), newFileAttributes(testFile), null, transformer);
+
+// First read - this should work and not delete the temp file
+try (InputStreamis1 = resource.getContents()){
+byte[] read1 = IOUtils.toByteArray(is1);
+assertEquals(largeContent.length, read1.length);
+ }
+
+// Second read - this should also work if the temp file wasn't prematurely deleted
+// This is the key test - without the fix, this would throw FileNotFoundException
+try (InputStreamis2 = resource.getContents()){
+byte[] read2 = IOUtils.toByteArray(is2);
+assertEquals(largeContent.length, read2.length);
+ }
+ }
+
+@Test
+voidtestFileResourceWithTransformerLargeFile() throwsIOException{
+// Create a large file that exceeds the DeferredFileOutputStream threshold (5MB)
+FiletestFile = newFile(tempDir, "large-test-file.bin");
+byte[] chunk = newbyte[1024 * 1024]; // 1MB chunks
+for (inti = 0; i < chunk.length; i++){
+chunk[i] = (byte) i;
+ }
+
+// Write 6MB to exceed the 5MB threshold
+try (OutputStreamos = Files.newOutputStream(testFile.toPath())){
+for (inti = 0; i < 6; i++){
+os.write(chunk);
+ }
+ }
+
+InputStreamTransformertransformer = (resource, inputStream) -> inputStream;
+
+PlexusIoFileResourceresource =
+newPlexusIoFileResource(testFile, testFile.getName(), newFileAttributes(testFile), null, transformer);
+
+// Verify we can read the content - this tests that the temp file
+// created by DeferredFileOutputStream is properly accessible
+longsize = resource.getSize();
+assertTrue(size > 5_000_000, "File should be larger than 5MB threshold");
+
+try (InputStreamis = resource.getContents()){
+assertNotNull(is);
+byte[] firstBytes = newbyte[1024];
+intread = is.read(firstBytes);
+assertEquals(1024, read);
+ }
+ }
+
+@Test
+voidtestFileResourceWithTransformerSmallFile() throwsIOException{
+// Test with a small file that stays in memory (below 5MB threshold)
+FiletestFile = newFile(tempDir, "small-test-file.txt");
+Stringcontent = "Hello, World!";
+Files.write(testFile.toPath(), content.getBytes(StandardCharsets.UTF_8));
+
+InputStreamTransformertransformer = (resource, inputStream) -> inputStream;
+
+PlexusIoFileResourceresource =
+newPlexusIoFileResource(testFile, testFile.getName(), newFileAttributes(testFile), null, transformer);
+
+// Multiple reads should work for small files too
+for (inti = 0; i < 3; i++){
+try (InputStreamis = resource.getContents()){
+StringreadContent = IOUtils.toString(is, StandardCharsets.UTF_8);
+assertEquals(content, readContent);
+ }
+ }
+ }
+}