Java tutorial
package com.yahoo.labs.samoa.streams.fs; /* * #%L * SAMOA * %% * Copyright (C) 2013 - 2014 Yahoo! Inc. * %% * Licensed 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. * #L% */ import java.io.BufferedWriter; import java.io.BufferedReader; import java.io.File; import java.io.FileWriter; import java.io.InputStream; import java.io.InputStreamReader; import java.io.IOException; import java.io.OutputStream; import java.io.OutputStreamWriter; import java.lang.SecurityException; import java.util.HashSet; import java.util.Iterator; import java.util.Set; import static org.junit.Assert.*; import org.junit.After; import org.junit.Assert; import org.junit.Before; import org.junit.Test; import org.apache.commons.io.FileUtils; public class LocalFileStreamSourceTest { private static final String BASE_DIR = "localfsTest"; private static final int NUM_FILES_IN_DIR = 4; private static final int NUM_NOISE_FILES_IN_DIR = 2; private LocalFileStreamSource streamSource; @Before public void setUp() throws Exception { streamSource = new LocalFileStreamSource(); } @After public void tearDown() throws Exception { FileUtils.deleteDirectory(new File(BASE_DIR)); } @Test public void testInitWithSingleFileAndExtension() { // write input file writeSimpleFiles(BASE_DIR, "txt", 1); // init with path to input file File inFile = new File(BASE_DIR, "1.txt"); String inFilePath = inFile.getAbsolutePath(); streamSource.init(inFilePath, "txt"); //assertions assertEquals("Size of filePaths is not correct.", 1, streamSource.getFilePathListSize(), 0); String fn = streamSource.getFilePathAt(0); assertEquals("Incorrect file in filePaths.", inFilePath, fn); } @Test public void testInitWithSingleFileAndNullExtension() { // write input file writeSimpleFiles(BASE_DIR, "txt", 1); // init with path to input file File inFile = new File(BASE_DIR, "1.txt"); String inFilePath = inFile.getAbsolutePath(); streamSource.init(inFilePath, null); //assertions assertEquals("Size of filePaths is not correct.", 1, streamSource.getFilePathListSize(), 0); String fn = streamSource.getFilePathAt(0); assertEquals("Incorrect file in filePaths.", inFilePath, fn); } @Test public void testInitWithFolderAndExtension() { // write input file writeSimpleFiles(BASE_DIR, null, NUM_NOISE_FILES_IN_DIR); writeSimpleFiles(BASE_DIR, "txt", NUM_FILES_IN_DIR); // init with path to input dir File inDir = new File(BASE_DIR); String inDirPath = inDir.getAbsolutePath(); streamSource.init(inDirPath, "txt"); //assertions assertEquals("Size of filePaths is not correct.", NUM_FILES_IN_DIR, streamSource.getFilePathListSize(), 0); Set<String> filenames = new HashSet<>(); for (int i = 1; i <= NUM_FILES_IN_DIR; i++) { String expectedFn = (new File(inDirPath, Integer.toString(i) + ".txt")).getAbsolutePath(); filenames.add(expectedFn); } for (int i = 0; i < NUM_FILES_IN_DIR; i++) { String fn = streamSource.getFilePathAt(i); assertTrue("Incorrect file in filePaths:" + fn, filenames.contains(fn)); } } @Test public void testInitWithFolderAndNullExtension() { // write input file writeSimpleFiles(BASE_DIR, null, NUM_FILES_IN_DIR); // init with path to input dir File inDir = new File(BASE_DIR); String inDirPath = inDir.getAbsolutePath(); streamSource.init(inDirPath, null); //assertions assertEquals("Size of filePaths is not correct.", NUM_FILES_IN_DIR, streamSource.getFilePathListSize(), 0); Set<String> filenames = new HashSet<>(); for (int i = 1; i <= NUM_FILES_IN_DIR; i++) { String expectedFn = (new File(inDirPath, Integer.toString(i))).getAbsolutePath(); filenames.add(expectedFn); } for (int i = 0; i < NUM_FILES_IN_DIR; i++) { String fn = streamSource.getFilePathAt(i); assertTrue("Incorrect file in filePaths:" + fn, filenames.contains(fn)); } } /* * getNextInputStream tests */ @Test public void testGetNextInputStream() { // write input files & noise files writeSimpleFiles(BASE_DIR, "txt", NUM_FILES_IN_DIR); // init with path to input dir streamSource.init(BASE_DIR, "txt"); // call getNextInputStream & assertions Set<String> contents = new HashSet<>(); for (int i = 1; i <= NUM_FILES_IN_DIR; i++) { contents.add(Integer.toString(i)); } for (int i = 0; i < NUM_FILES_IN_DIR; i++) { InputStream inStream = streamSource.getNextInputStream(); assertNotNull("Unexpected end of input stream list.", inStream); BufferedReader rd = new BufferedReader(new InputStreamReader(inStream)); String inputRead = null; try { inputRead = rd.readLine(); } catch (IOException ioe) { fail("Fail reading from stream at index:" + i + ioe.getMessage()); } assertTrue("File content is incorrect.", contents.contains(inputRead)); Iterator<String> it = contents.iterator(); while (it.hasNext()) { if (it.next().equals(inputRead)) { it.remove(); break; } } } // assert that another call to getNextInputStream will return null assertNull("Call getNextInputStream after the last file did not return null.", streamSource.getNextInputStream()); } /* * getCurrentInputStream tests */ public void testGetCurrentInputStream() { // write input files & noise files writeSimpleFiles(BASE_DIR, "txt", NUM_FILES_IN_DIR); // init with path to input dir streamSource.init(BASE_DIR, "txt"); // call getNextInputStream, getCurrentInputStream & assertions for (int i = 0; i <= NUM_FILES_IN_DIR; i++) { // test also after-end-of-list InputStream inStream1 = streamSource.getNextInputStream(); InputStream inStream2 = streamSource.getCurrentInputStream(); assertSame("Incorrect current input stream.", inStream1, inStream2); } } /* * reset tests */ public void testReset() { // write input files & noise files writeSimpleFiles(BASE_DIR, "txt", NUM_FILES_IN_DIR); // init with path to input dir streamSource.init(BASE_DIR, "txt"); // Get the first input string InputStream firstInStream = streamSource.getNextInputStream(); String firstInput = null; assertNotNull("Unexpected end of input stream list.", firstInStream); BufferedReader rd1 = new BufferedReader(new InputStreamReader(firstInStream)); try { firstInput = rd1.readLine(); } catch (IOException ioe) { fail("Fail reading from stream at index:0" + ioe.getMessage()); } // call getNextInputStream a few times streamSource.getNextInputStream(); // call reset, call next, assert that output is 1 (the first file) try { streamSource.reset(); } catch (IOException ioe) { fail("Fail resetting stream source." + ioe.getMessage()); } InputStream inStream = streamSource.getNextInputStream(); assertNotNull("Unexpected end of input stream list.", inStream); BufferedReader rd2 = new BufferedReader(new InputStreamReader(inStream)); String inputRead = null; try { inputRead = rd2.readLine(); } catch (IOException ioe) { fail("Fail reading from stream at index:0" + ioe.getMessage()); } assertEquals("File content is incorrect.", firstInput, inputRead); } private void writeSimpleFiles(String path, String ext, int numOfFiles) { // Create folder File folder = new File(path); if (!folder.exists()) { try { folder.mkdir(); } catch (SecurityException se) { fail("Failed creating directory:" + path + se); } } // Write files for (int i = 1; i <= numOfFiles; i++) { String fn = null; if (ext != null) { fn = Integer.toString(i) + "." + ext; } else { fn = Integer.toString(i); } try { FileWriter fwr = new FileWriter(new File(path, fn)); fwr.write(Integer.toString(i)); fwr.close(); } catch (IOException ioe) { fail("Fail writing to input file: " + fn + " in directory: " + path + ioe.getMessage()); } } } }