使用 Java 操作文件的 10 大最佳实践

// 使用 Path 类操作文件
Path path = Paths.get("my-file.txt");
Files.readAllBytes(path);

// 使用 nio.Path 类操作文件
java.nio.file.Path path = java.nio.file.Paths.get("my-file.txt");
java.nio.file.Files.readAllBytes(path);

try (BufferedReader reader = new BufferedReader(new FileReader("my-file.txt"))) {
String line;
while ((line = reader.readLine()) != null) {
// Process the line
}
} catch (IOException e) {
// Handle the exception
}

// 创建一个新文件
Files.createFile(Paths.get("my-file.txt"));

// 写入文件
Files.write(Paths.get("my-file.txt"), "Hello world!".getBytes());

// 读取文件
byte[] bytes = Files.readAllBytes(Paths.get("my-file.txt"));
String content = new String(bytes);

// 删除文件
Files.delete(Paths.get("my-file.txt"));

// 写入文件
try (BufferedWriter writer = new BufferedWriter(new FileWriter("my-file.txt"))) {
writer.write("Hello world!");
} catch (IOException e) {
// Handle the exception
}

// 读取文件
try (BufferedReader reader = new BufferedReader(new FileReader("my-file.txt"))) {
String line;
while ((line = reader.readLine()) != null) {
// Process the line
}
} catch (IOException e) {
// Handle the exception
}

// 写入文件
try (FileChannel channel = FileChannel.open(Paths.get("my-file.txt"), StandardOpenOption.WRITE)) {
MappedByteBuffer buffer = channel.map(FileChannel.MapMode.READ_WRITE, 0, 1024);
buffer.put("Hello world!".getBytes());
} catch (IOException e) {
// Handle the exception
}

// 读取文件
try (FileChannel channel = FileChannel.open(Paths.get("my-file.txt"), StandardOpenOption.READ)) {
MappedByteBuffer buffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, 1024);
String content = new String(buffer);
} catch (IOException e) {
// Handle the exception
}

// 遍历文件和目录
Files.walk(Paths.get("/home/user"), new SimpleFileVisitor<Path>() {
@Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) throws IOException {
// Process the file
return FileVisitResult.CONTINUE;
}
});

// 复制文件
Files.copy(Paths.get("src.txt"), Paths.get("dest.txt"));

// 移动文件
Files.move(Paths.get("src.txt"), Paths.get("dest.txt"));

// 删除文件
Files.delete(Paths.get("my-file.txt"));

// 获取文件信息
File file = new File("my-file.txt");
System.out.println(file.getName());
System.out.println(file.getPath());
System.out.println(file.length());

// 在文件中随机访问数据
try (RandomAccessFile file = new RandomAccessFile("my-file.txt", "rw")) {
// Seek to a specific position in the file
file.seek(100);

// Read data from the file
byte[] bytes = new byte[10];
file.read(bytes);
} catch (IOException e) {
// Handle the exception
}

// 选择性地写入文件
FileFilter filter = new FileFilter() {
@Override
public boolean accept(File file) {
return file.getName().endsWith(".txt");
}
};

try (FileOutputStream output = new FileOutputStream("output.txt")) {
Files.copy(Files.list(Paths.get("/home/user")).filter(filter), output);
} catch (IOException e) {
// Handle the exception
}