如何通过读取文本文件来替换java中两个字符串之间的字符串

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public class FileStringReplacement {
    public static void main(String[] args) {
        String filePath = "path/to/file.txt"; // 替换前的文本文件路径
        String searchString = "string1"; // 要替换的字符串1
        String replacementString = "string2"; // 替换后的字符串2

        try {
            // 读取文本文件
            BufferedReader reader = new BufferedReader(new FileReader(filePath));
            StringBuilder stringBuilder = new StringBuilder();
            String line;
            while ((line = reader.readLine()) != null) {
                stringBuilder.append(line);
                stringBuilder.append(System.lineSeparator());
            }
            String content = stringBuilder.toString();
            reader.close();

            // 替换字符串
            String replacedContent = content.replace(searchString, replacementString);

            // 写入替换后的内容到文本文件
            FileWriter writer = new FileWriter(filePath);
            writer.write(replacedContent);
            writer.close();

            System.out.println("字符串替换成功！");
        } catch (IOException e) {
            System.out.println("发生错误：" + e.getMessage());
        }
    }
}