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turingfly
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NIO.2
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‎Java-8/src/nio2/CreatingPaths.java

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package nio2;
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import java.io.File;
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import java.net.URI;
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import java.net.URISyntaxException;
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import java.nio.file.FileSystem;
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import java.nio.file.FileSystems;
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import java.nio.file.Path;
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import java.nio.file.Paths;
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/**
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*
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* @author chengfeili
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* Jun 20, 2017 9:31:31 AM
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*
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* Path is a direct replacement for the legacy java.io.File class, and
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* conceptually it contains many of the same properties. For example,
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* both File and Path objects may refer to a file or a directory. Both
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* also may refer to an absolute path or relative path within the file
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* system.
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*/
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public class CreatingPaths {
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public void path() {
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Path path1 = Paths.get("/home/zoo");
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Path path2 = Paths.get("/", "home", "zoo");
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// Use URI values for both local and remote paths
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// URIs must reference absolute paths at runtime;
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Path path3 = Paths.get("file:///home/zoo");
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URI uri = path3.toUri();
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try {
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FileSystem fileSystem = FileSystems.getFileSystem(new URI("http://www.selikoff.net"));
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Path path4 = fileSystem.getPath("duck.txt");
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} catch (URISyntaxException e) {
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}
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// Legacy File Instances
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File file = new File("/home/zoo");
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Path path5 = file.toPath();
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File file2 = path5.toFile();
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}
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}

‎Java-8/src/nio2/InteractingWithPathsAndFiles.java

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package nio2;
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import java.io.BufferedReader;
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import java.io.BufferedWriter;
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import java.io.FileInputStream;
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import java.io.FileOutputStream;
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import java.io.IOException;
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import java.io.InputStream;
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import java.io.OutputStream;
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import java.nio.charset.Charset;
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import java.nio.file.Files;
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import java.nio.file.Path;
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import java.nio.file.Paths;
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import java.util.ArrayList;
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import java.util.List;
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/**
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*
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* @author chengfeili
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* Jun 20, 2017 9:57:52 PM
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*
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* Path Object VS Actual File A Path object is not a file but a
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* representation of a location with the file system. Most operations
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* available in the Path and Paths classes can be accomplished
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* regardless of whether the underlying file that the path object
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* references actually exists.
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*
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* Java is fond of singular names for container classes and plural names
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* for factory and helper classes. I
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*
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* the Files class operates on Path instances, not File instances. Keep
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* in mind that File belongs to the legacy java.io API, while Files
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* belongs to the NIO.2 API.
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*/
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public class InteractingWithPathsAndFiles {
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public void testFile() {
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Files.exists(Paths.get("/home/zoo"));
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Files.exists(Paths.get("/home/zoo/dog.jpg"));
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/**
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* The isSameFile() method first checks if the Path objects are equal in
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* terms of equal(), and if so, it automatically returns true without
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* checking to see if either files exists. If the Path object equals()
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* comparison returns false, then it locates each file to which the path
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* refers in the file system and determines if they are the same,
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* throwing a checked IOException if either file does not exist.
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*/
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try {
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// cobra is a symbolic link to the snake
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System.out.println(Files.isSameFile(Paths.get("/user/home/cobra"), Paths.get("/user/home/snake"))); // true
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System.out.println(Files.isSameFile(Paths.get("/user/tree/../monkey"), Paths.get("/user/monkey"))); // true
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System.out.println(Files.isSameFile(Paths.get("/leaves/./giraffe.exe"), Paths.get("/leaves/giraffe.exe"))); // false
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System.out.println(Files.isSameFile(Paths.get("/flamingo/tail.data"), Paths.get("/cardinal/tail.data")));
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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/**
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*
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* The example creates a new directory, field, in the directory /bison,
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* assuming /bison exists; or else an exception is thrown. Contrast this
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* with the second example that creates the directory green along with
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* any of the following parent directories if they do not already exist,
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* such as /bison, /bison/field, or /bison/pasture.
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*/
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try {
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Files.createDirectory(Paths.get("/bison/field"));
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Files.createDirectories(Paths.get("/bison/field/pasture/green"));
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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/**
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* Duplicating File Contents with copy()
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*
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* The copy() method throws the checked IOException, such as when the
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* file or directory does not exist or cannot be read. Directory copies
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* are shallow rather than deep, meaning that files and sub directories
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* within the directory are not copied. T
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*/
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try {
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Files.copy(Paths.get("/panda"), Paths.get("/panda-save"));
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Files.copy(Paths.get("/panda/bamboo.txt"), Paths.get("/panda-save/bamboo.txt"));
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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try (InputStream is = new FileInputStream("source-data.txt");
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OutputStream out = new FileOutputStream("output-data.txt")) {
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// Copy stream data to file
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Files.copy(is, Paths.get("c:\\mammals\\wolf.txt"));
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// Copy file data to stream
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Files.copy(Paths.get("c:\\fish\\clown.xsl"), out);
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} catch (IOException e) {
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// Handle file I/O exception... }
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}
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// Changing a File Location with move()
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try {
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Files.move(Paths.get("c:\\zoo"), Paths.get("c:\\zoo-new"));
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Files.move(Paths.get("c:\\user\\addresses.txt"), Paths.get("c:\\zoo-new\\addresses.txt"));
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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/**
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* Removing a File with delete() and deleteIfExists()
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*
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* The first example deletes the features.txt file in the vulture
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* directory, and it throws a NoSuchFileException if the file or
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* directory does not exist. The second example deletes the pigeon
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* directory assuming it is empty. If the pigeon directory does not
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* exist, then the second line will not throw an exception.
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*/
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try {
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Files.delete(Paths.get("/vulture/feathers.txt"));
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Files.deleteIfExists(Paths.get("/pigeon"));
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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/**
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*
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* Reading and Writing File Data with newBufferedReader() and
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* newBufferedWriter()
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*/
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Path path = Paths.get("/animals/gopher.txt");
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try (BufferedReader reader = Files.newBufferedReader(path, Charset.forName("US-ASCII"))) {
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// Read from the stream
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String currentLine = null;
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while ((currentLine = reader.readLine()) != null)
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System.out.println(currentLine);
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} catch (IOException e) {
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// Handle file I/O exception... }
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}
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try (BufferedWriter writer = Files.newBufferedWriter(path, Charset.forName("UTF-16"))) {
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writer.write("Hello World");
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} catch (IOException e) {
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// Handle file I/O exception... }
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}
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/**
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* Reading Files with readAllLines()
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*/
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try {
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final List<String> lines = Files.readAllLines(path);
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for (String line : lines) {
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System.out.println(line);
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}
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} catch (IOException e) {
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// Handle file I/O exception...
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}
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}
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}

‎Java-8/src/nio2/UnderstandingFileAttributes.java

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package nio2;
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/**
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*
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* @author chengfeili
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* Jun 21, 2017 9:07:47 PM
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*
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*/
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public class UnderstandingFileAttributes {
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}

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