Java文件输入输出：读写操作实例

原创小灰灰 2024-11-06 23:45 7阅读 0赞

Java提供了多种方式来处理文件的输入输出操作。以下是一些基本的文件读写操作的实例：

###1. 使用`FileInputStream`和`FileOutputStream`类```javaimport java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

public class FileIOExample {
 public static void main(String[] args) {
String sourceFile = "source.txt";
String destFile = "destination.txt";

try (FileInputStream fis = new FileInputStream(sourceFile);
 FileOutputStream fos = new FileOutputStream(destFile)) {
int content;
 while ((content = fis.read()) != -1) {
 fos.write(content);
 }
} catch (IOException e) {
e.printStackTrace();
 }
 }
}
```###2. 使用`BufferedReader`和`BufferedWriter`类```javaimport java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class BufferedFileIOExample {
 public static void main(String[] args) {
String sourceFile = "source.txt";
String destFile = "destination.txt";

try (BufferedReader br = new BufferedReader(new FileReader(sourceFile));
 BufferedWriter bw = new BufferedWriter(new FileWriter(destFile))) {
String line;
 while ((line = br.readLine()) != null) {
 bw.write(line);
 bw.newLine();
 }
} catch (IOException e) {
e.printStackTrace();
 }
 }
}
```###3. 使用`Files`类（Java7及以上）

```javaimport java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.stream.Stream;

public class NIOFileIOExample {
 public static void main(String[] args) {
String sourceFile = "source.txt";
String destFile = "destination.txt";

try (Stream<String> lines = Files.lines(Paths.get(sourceFile))) {
 lines.forEach(line -> {
 try {
Files.write(Paths.get(destFile), (line + System.lineSeparator()).getBytes());
} catch (IOException e) {
e.printStackTrace();
 }
 });
} catch (IOException e) {
e.printStackTrace();
 }
 }
}
```###4. 使用`ObjectInputStream`和`ObjectOutputStream`类（用于对象序列化）

```javaimport java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.Serializable;

public class ObjectFileIOExample {
 public static void main(String[] args) {
String fileName = "data.obj";

try {
//写入对象 ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream(fileName));
oos.writeObject("Hello, World!");
oos.close();

//读取对象ObjectInputStream ois = new ObjectInputStream(new FileInputStream(fileName));
Object obj = ois.readObject();
ois.close();

System.out.println(obj);
} catch (Exception e) {
e.printStackTrace();
 }
 }
}
```这些例子展示了如何使用Java进行基本的文件读写操作。根据你的具体需求，你可以选择适合的方法来处理文件。记得在实际应用中处理异常和资源释放。