Add helper class for mass-regression-tests which scans a directory and provides

the matching FileHandlers for each found file.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1860686 13f79535-47bb-0310-9956-ffa450edef68

src/integrationtest/org/apache/poi/POIFileScanner.java

@@ -0,0 +1,170 @@
+/*
+ *  ====================================================================
+ *    Licensed to the Apache Software Foundation (ASF) under one or more
+ *    contributor license agreements.  See the NOTICE file distributed with
+ *    this work for additional information regarding copyright ownership.
+ *    The ASF licenses this file to You under the Apache License, Version 2.0
+ *    (the "License"); you may not use this file except in compliance with
+ *    the License.  You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ * ====================================================================
+ */
+
+package org.apache.poi;
+
+import org.apache.poi.hssf.usermodel.HSSFWorkbook;
+import org.apache.poi.hwpf.HWPFDocument;
+import org.apache.poi.poifs.filesystem.FileMagic;
+import org.apache.poi.poifs.filesystem.POIFSFileSystem;
+import org.apache.poi.ss.usermodel.WorkbookFactory;
+import org.apache.poi.stress.FileHandler;
+import org.apache.poi.xwpf.usermodel.XWPFDocument;
+import org.apache.tools.ant.DirectoryScanner;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.util.AbstractMap;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * Helper class to scan a folder for files and return a collection of
+ * found files together with the matching {@link FileHandler}.
+ *
+ * Can also be used to get the appropriate FileHandler for a single file.
+ */
+public class POIFileScanner {
+    /**
+     * Scan a folder for files and return a collection of
+     * found files together with the matching {@link FileHandler}.
+     *
+     * Note: unknown files will be assigned to {@link org.apache.poi.TestAllFiles.NullFileHandler}
+     *
+     * @param rootDir The directory to scan
+     * @return A collection with file-FileHandler pairs which can be used for running tests on that file
+     * @throws IOException If determining the file-type fails
+     */
+    public static Collection<Map.Entry<String, FileHandler>> scan(File rootDir) throws IOException {
+
+        DirectoryScanner scanner = new DirectoryScanner();
+        scanner.setBasedir(rootDir);
+
+        scanner.setExcludes(TestAllFiles.SCAN_EXCLUDES);
+
+        System.out.println("Scanning for files in " + rootDir);
+
+        scanner.scan();
+
+        System.out.println("Handling " + scanner.getIncludedFiles().length + " files");
+
+        List<Map.Entry<String, FileHandler>> files = new ArrayList<>();
+        for(String file : scanner.getIncludedFiles()) {
+            // breaks files with slash in their name on Linux:
+            // file = file.replace('\\', '/'); // ... failures/handlers lookup doesn't work on windows otherwise
+
+            FileHandler fileHandler = getFileHandler(rootDir, file);
+
+            files.add(new AbstractMap.SimpleImmutableEntry<>(file, fileHandler));
+
+            if(files.size() % 100 == 0) {
+                System.out.print(".");
+                if(files.size() % 100_000 == 0) {
+                    System.out.println(file);
+                }
+            }
+        }
+        System.out.println();
+
+        return files;
+    }
+
+    /**
+     * Get the FileHandler for a single file
+     *
+     * @param rootDir The directory where the file resides
+     * @param file The name of the file without directory
+     * @return The matching {@link FileHandler}, A {@link org.apache.poi.TestAllFiles.NullFileHandler}
+     *          is returned if no match is found
+     * @throws IOException If determining the file-type fails
+     */
+    protected static FileHandler getFileHandler(File rootDir, String file) throws IOException {
+        FileHandler fileHandler = TestAllFiles.HANDLERS.get(TestAllFiles.getExtension(file));
+        if(fileHandler == null) {
+            File testFile = new File(rootDir, file);
+            FileMagic magic = FileMagic.valueOf(testFile);
+            // if we have a file-type that we can read, but no extension, we try to determine the
+            // file type manually
+
+            switch(magic) {
+                case OLE2: {
+                    try {
+                        try (POIFSFileSystem fs = new POIFSFileSystem(testFile, true)) {
+                            HSSFWorkbook.getWorkbookDirEntryName(fs.getRoot());
+                        }
+
+                        // we did not get an exception, so it seems this is a HSSFWorkbook
+                        fileHandler = TestAllFiles.HANDLERS.get(".xls");
+                    } catch (IOException | RuntimeException e) {
+                        try {
+                            try (FileInputStream istream = new FileInputStream(testFile)) {
+                                try (HWPFDocument ignored = new HWPFDocument(istream)) {
+                                    // seems to be a valid document
+                                    fileHandler = TestAllFiles.HANDLERS.get(".doc");
+                                }
+                            }
+                        } catch (IOException | RuntimeException e2) {
+                            System.out.println("Could not open POIFSFileSystem for OLE2 file " + testFile + ": " + e + " and " + e2);
+                            fileHandler = new TestAllFiles.NullFileHandler();
+                        }
+                    }
+                    break;
+                }
+                case OOXML: {
+                    try {
+                        WorkbookFactory.create(testFile);
+
+                        // seems to be a valid workbook
+                        fileHandler = TestAllFiles.HANDLERS.get(".xlsx");
+                    } catch (IOException | RuntimeException e) {
+                        try {
+                            try (FileInputStream is = new FileInputStream(testFile)) {
+                                try (XWPFDocument ignored = new XWPFDocument(is)) {
+                                    // seems to be a valid document
+                                    fileHandler = TestAllFiles.HANDLERS.get(".docx");
+                                }
+                            }
+                        } catch (IOException | RuntimeException e2) {
+                            System.out.println("Could not open POIFSFileSystem for OOXML file " + testFile + ": " + e + " and " + e2);
+                            fileHandler = new TestAllFiles.NullFileHandler();
+                        }
+                    }
+                    break;
+                }
+
+                // do not warn about a few detected file types
+                case RTF:
+                case PDF:
+                case HTML:
+                    fileHandler = new TestAllFiles.NullFileHandler();
+                    break;
+            }
+
+            if(fileHandler == null) {
+                System.out.println("Did not get a handler for extension " + TestAllFiles.getExtension(file) +
+                        " of file " + file + ": " + magic);
+                fileHandler = new TestAllFiles.NullFileHandler();
+            }
+        }
+        return fileHandler;
+    }
+}