@Test public void testReadFileContents() throws Exception { Path testPath = new Path(TestUtils.createTempDir().getAbsolutePath(), "tempFile"); FileSystem fs = testPath.getFileSystem(new Configuration()); fs.create(testPath); // 1) Read back empty file String emptyString = HadoopStoreBuilderUtils.readFileContents(fs, testPath, 1024); Assert.assertEquals(emptyString.length(), 0); // 2) Read back random bytes byte[] randomBytes = writeRandomData(testPath, 10); // Read back data Assert.assertEquals( HadoopStoreBuilderUtils.readFileContents(fs, testPath, 1024), new String(randomBytes)); // 3) Write a json string fs.delete(testPath, true); fs.create(testPath); ReadOnlyStorageMetadata metadata = new ReadOnlyStorageMetadata(); metadata.add(ReadOnlyStorageMetadata.FORMAT, ReadOnlyStorageFormat.READONLY_V2.getCode()); // Write file contents new FileOutputStream(testPath.toString()).write(metadata.toJsonString().getBytes()); ReadOnlyStorageMetadata readMetadata = new ReadOnlyStorageMetadata(HadoopStoreBuilderUtils.readFileContents(fs, testPath, 1024)); Assert.assertEquals( readMetadata.get(ReadOnlyStorageMetadata.FORMAT), ReadOnlyStorageFormat.READONLY_V2.getCode()); }