Java文件读取与写入的几种方式

本是古典何须时尚 2023-10-13 14:20 8阅读 0赞

### Java读取文件内容的六种方法（详细教程） ###

> 第一种FileInputStream 文件读取

FileInputStream inputStream = null;
    try {
        
        File file = new File("file.txt");
        inputStream = new FileInputStream(file);
        int content;
        while ((content = inputStream.read()) != -1) {
        
            // 处理读取到的字节
        }
    } catch (IOException e) {
        
        e.printStackTrace();
    } finally {
        
        if (inputStream != null) {
        
            try {
        
                inputStream.close();
            } catch (IOException e) {
        
                e.printStackTrace();
            }
        }
    }

> BufferedReader：文件读取

BufferedReader reader = null;
    try {
        
        File file = new File("file.txt");
        FileReader fileReader = new FileReader(file);
        reader = new BufferedReader(fileReader);
        String content;
        while ((content = reader.readLine()) != null) {
        
            // 处理读取到的一行字符串
        }
    } catch (IOException e) {
        
        e.printStackTrace();
    } finally {
        
        if (reader != null) {
        
            try {
        
                reader.close();
            } catch (IOException e) {
        
                e.printStackTrace();
            }
        }
    }

> 文件写入FileOutputStream：

FileOutputStream outputStream = null;
    try {
        
        File file = new File("file.txt");
        outputStream = new FileOutputStream(file);
        String content = "Hello, world!";
        byte[] bytes = content.getBytes();
        outputStream.write(bytes);
    } catch (IOException e) {
        
        e.printStackTrace();
    } finally {
        
        if (outputStream != null) {
        
            try {
        
                outputStream.close();
            } catch (IOException e) {
        
                e.printStackTrace();
            }
        }
    }

> PrintWriter：文件写入

PrintWriter writer = null;
    try {
        
        File file = new File("file.txt");
        FileWriter fileWriter = new FileWriter(file);
        writer = new PrintWriter(fileWriter);
        String content = "Hello, world!";
        writer.println(content);
    } catch (IOException e) {
        
        e.printStackTrace();
    }