Day 246: work with files example - bad examples, I'm sorry

src/main/java/com/demotivirus/Day_246/FindInBigFile.java

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+package com.demotivirus.Day_246;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.nio.charset.Charset;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.regex.Pattern;
+
+public class FindInBigFile {
+    public static void main(String[] args) throws IOException {
+        Path path = Path.of("src/main/java/com/demotivirus/Day_246/chinese.txt");
+        System.out.println(countOccurrences(path, "11"));
+        System.out.println(countOccurrences(path, "22"));
+    }
+
+    private static int countOccurrences(Path path, String text) {
+        return countOccurrences(path, text, StandardCharsets.UTF_16);
+    }
+
+    private static int countOccurrences(Path path, String text, Charset charset) {
+        if (charset == null)
+            charset = StandardCharsets.UTF_16;
+
+        int count = 0;
+
+        try (BufferedReader br = Files.newBufferedReader(path, charset)) {
+            String line;
+            while ((line = br.readLine()) != null) { //not work correctly
+                count += countStringInInt(line, text);
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        return count;
+    }
+
+    private static int countStringInInt(String string, String toFind) {
+        return string.split(Pattern.quote(toFind), -1).length - 1;
+    }
+}

src/main/java/com/demotivirus/Day_246/ReadBigFileExample.java

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+package com.demotivirus.Day_246;
+
+import java.io.IOException;
+import java.nio.MappedByteBuffer;
+import java.nio.channels.FileChannel;
+import java.nio.file.Path;
+import java.nio.file.StandardOpenOption;
+import java.util.EnumSet;
+
+public class ReadBigFileExample {
+    public static void main(String[] args) throws IOException {
+        Path chinese = Path.of("src/main/java/com/demotivirus/Day_246/chinese.txt");
+//        List<String> allLines = Files.readAllLines(chinese, StandardCharsets.UTF_16);
+//        allLines.forEach(System.out::println);
+
+        int MAP_SIZE = 524880; //5 MB
+        try (FileChannel fileChannel = (FileChannel.open(chinese, EnumSet.of(StandardOpenOption.READ)))) {
+            int position = 0;
+            long length = fileChannel.size();
+
+            while (position < length) {
+                long remaining = length - position;
+                int bytesToMap = (int) Math.min(MAP_SIZE, remaining);
+
+                MappedByteBuffer mappedByteBuffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, position, bytesToMap);
+                //to do
+
+                position += bytesToMap;
+            }
+        }
+    }
+}

src/main/java/com/demotivirus/Day_246/ReadBinaryFiles.java

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+package com.demotivirus.Day_246;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.attribute.BasicFileAttributes;
+
+public class ReadBinaryFiles {
+    public static void main(String[] args) throws IOException {
+        Path binaryFile = Paths.get("src/main/java/com/demotivirus/Day_246/ReadBigFileExample.java");
+        int fileSize = (int) Files.readAttributes(binaryFile, BasicFileAttributes.class).size();
+
+        final byte[] buffer = new byte[fileSize];
+
+        try (InputStream is = new FileInputStream(binaryFile.toString())) {
+            int i;
+            while ((i = is.read(buffer)) != -1) {
+                System.out.println("Reading...");
+                System.out.println(is.read());
+            }
+        }
+    }
+}

src/main/java/com/demotivirus/Day_246/WriteBinaryFile.java

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+package com.demotivirus.Day_246;
+
+import java.io.BufferedOutputStream;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
+import java.nio.file.attribute.BasicFileAttributes;
+
+public class WriteBinaryFile {
+    public static void main(String[] args) throws IOException {
+        Path binaryFile = Paths.get("src/main/java/com/demotivirus/Day_246/ReadBigFileExample.java");
+        int fileSize = (int) Files.readAttributes(binaryFile, BasicFileAttributes.class).size();
+
+        final byte[] buffer = new byte[fileSize];
+
+        BufferedOutputStream bufferedOutputStream = new BufferedOutputStream(
+                Files.newOutputStream(binaryFile, StandardOpenOption.CREATE,
+                StandardOpenOption.WRITE));
+        bufferedOutputStream.write(buffer);
+    }
+}

src/main/java/com/demotivirus/Day_246/WriteTextFile.java

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+package com.demotivirus.Day_246;
+
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.StandardOpenOption;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+public class WriteTextFile {
+    private static Logger LOGGER = Logger.getLogger(WriteTextFile.class.getName());
+    public static void main(String[] args) {
+        Path textFile = Paths.get("written-file.txt");
+
+        try (BufferedWriter bw = Files.newBufferedWriter(textFile, StandardCharsets.UTF_8, StandardOpenOption.CREATE, StandardOpenOption.WRITE)) {
+            bw.write("Code everyday for be harder");
+            bw.newLine();
+            bw.write("Repeat ten if you not understand");
+        } catch (IOException ex) {
+            LOGGER.log(Level.WARNING, "Something wos wrong {}", ex.getMessage());
+        }
+    }
+}

src/main/java/com/demotivirus/Day_246/chinese.txt

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+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+你好世界中文
+111111
+222
+22
+22

written-file.txt

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+Code everyday for be harder
+Repeat ten if you not understand