[SNAP-3479] Exception in decode qualification of ZnapProductReader

not only productRoot could have been null but also the return of productRoot.getFileName()

Author: marpet

snap-znap/src/main/java/org/esa/snap/dataio/znap/ZnapProductReaderPlugIn.java

@@ -54,7 +54,8 @@ public DecodeQualification getDecodeQualification(Object input) {
         } else {
             productRoot = inputPath.getParent();
         }
-        final boolean isValidRootDirName = productRoot != null && productRoot.getFileName().toString().toLowerCase().endsWith(ZNAP_CONTAINER_EXTENSION);
+        Path productRootName = productRoot != null ? productRoot.getFileName() : null;
+        final boolean isValidRootDirName = productRootName != null && productRootName.toString().toLowerCase().endsWith(ZNAP_CONTAINER_EXTENSION);
         if (isValidRootDirName) {
             final boolean productRootIsDirectory = Files.isDirectory(productRoot);
             final Path productHeader = productRoot.resolve(FILENAME_DOT_ZGROUP);
@@ -74,7 +75,7 @@ public DecodeQualification getDecodeQualification(Object input) {
                 }
             }
         }
-        final boolean isValidZnapZipArchiveName = productRoot != null && productRoot.getFileName().toString().toLowerCase().endsWith(ZNAP_ZIP_CONTAINER_EXTENSION);
+        final boolean isValidZnapZipArchiveName = productRootName != null && productRootName.toString().toLowerCase().endsWith(ZNAP_ZIP_CONTAINER_EXTENSION);
         if (isValidZnapZipArchiveName) {
             try (ZipStore zipStore = new ZipStore(productRoot)) {
                 final InputStream productHeaderStream = zipStore.getInputStream(FILENAME_DOT_ZGROUP);

snap-znap/src/test/java/org/esa/snap/dataio/znap/ZnapProductReaderPlugInTest_getDecodeQualification.java

@@ -19,21 +19,26 @@
 package org.esa.snap.dataio.znap;
 
 import com.bc.zarr.ZarrConstants;
+import com.google.common.jimfs.Configuration;
 import com.google.common.jimfs.Jimfs;
 import org.esa.snap.core.dataio.DecodeQualification;
 import org.esa.snap.core.util.io.TreeDeleter;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 
+import java.io.File;
 import java.io.IOException;
 import java.nio.file.FileSystem;
 import java.nio.file.Files;
 import java.nio.file.Path;
+import java.nio.file.Paths;
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
+import static org.junit.Assume.assumeNotNull;
 
 public class ZnapProductReaderPlugInTest_getDecodeQualification {
 
@@ -95,7 +100,7 @@ public void decodeQualification_INTENDED_perfectMatch_inputStringObject() throws
 
     @Test
     public void decodeQualification_INTENDED_perfectMatch_inputHasNoParent() throws IOException {
-        try(FileSystem fileSystem = Jimfs.newFileSystem()) {
+        try (FileSystem fileSystem = Jimfs.newFileSystem()) {
             Path path = fileSystem.getPath("snap_zarr_product_root_dir.znap");
 
             Path dataDir = path.resolve("a_raster_data_dir");
@@ -127,17 +132,30 @@ public void decodeQualification_UNABLE_inputObjectIsNullOrCanNotBeConvertedToPat
     }
 
     @Test
-    public void decodeQualification_UNABLE_productRootDoesNotExist() {
-        // No file or directory as expected
+    public void decodeQualification_UNABLE_productRootDoesNotExist() throws IOException {
+        try (FileSystem fileSystem = Jimfs.newFileSystem()) {
+            Path path = fileSystem.getPath("any_not_supported_file.tar");
 
-        final DecodeQualification decodeQualification = plugIn.getDecodeQualification(productRoot);
+            final DecodeQualification decodeQualification = plugIn.getDecodeQualification(path);
+            assertThat(decodeQualification, is(equalTo(DecodeQualification.UNABLE)));
+        }
+
+    }
+
+    @Test()
+    public void decodeQualification_UNABLE_AnyFileAtRootLevel() {
+        String systemDrive = System.getenv("SystemDrive");
+        assumeNotNull(systemDrive); // only on windows not null
+        Path root = Paths.get(systemDrive);
+        Path notValid = root.resolve("any_not_supported_file.notznap");
 
+        final DecodeQualification decodeQualification = plugIn.getDecodeQualification(notValid);
         assertThat(decodeQualification, is(equalTo(DecodeQualification.UNABLE)));
     }
 
     @Test
     public void decodeQualification_UNABLE_aZGroupFileWhichHasNoParentDir() throws IOException {
-        try(FileSystem fileSystem = Jimfs.newFileSystem()) {
+        try (FileSystem fileSystem = Jimfs.newFileSystem()) {
             Path path = fileSystem.getPath("any_zarr_group_file_without_parent.zgroup");
             final DecodeQualification decodeQualification = plugIn.getDecodeQualification(path);