Java代码如何将一个文件读取---并转换为字符串存储呢?

实现思路:
    1.使用FileReader读取文件
    2.使用fileReader.readLine()读取字符串

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

public String readFile(String fileName) throws IOException {
    BufferedReader br = new BufferedReader(new FileReader(fileName));
    try {
        StringBuilder sb = new StringBuilder();
        String line = br.readLine();

        while (line != null) {
            sb.append(line);
            sb.append("\n");
            line = br.readLine();
        }
        return sb.toString();
    } finally {
        br.close();
    }
}