对文本的读出和写入字符串操作

代码示例：

package filestring;

import java.io.*;

public class FileTest {
    public static void main(String[] args) {
        try {
            // 创建目录
            File dir = new File("Chapter");
            dir.mkdirs();
            
            // 创建文件
            File f = new File("D:/eclipseWJ/HelloWorld/Chapter/File1.txt");
            f.createNewFile();
            
            // 写入文件
            FileWriter writer = new FileWriter(f);
            BufferedWriter bufferedwriter = new BufferedWriter(writer);
            bufferedwriter.write("File1");
            bufferedwriter.close();

            // 输出目录中的文件
            if (dir.isDirectory()) {
                String[] fileContents = dir.list();
                for (String i : fileContents)
                    System.out.println(i);
            }

            // 读出文件内容
            FileReader fileReader = new FileReader(f);
            BufferedReader reader = new BufferedReader(fileReader);
            String line = null;
            while ((line = reader.readLine()) != null)
                System.out.println(line);
            reader.close();

        } catch (IOException ex) {
            ex.printStackTrace();
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}