一种方法是使用 String.replaceAll():

File log= new File("log.txt");
String search = "textFiles/a\\.txt";  // <- changed to work with String.replaceAll()
String replacement = "something/bob.txt";
//file reading
FileReader fr = new FileReader(log);
String s;
try {
    BufferedReader br = new BufferedReader(fr);

    while ((s = br.readLine()) != null) {
        s.replaceAll(search, replacement);
        // do something with the resulting line
    }
}

您还可以使用正则表达式或 String.indexOf() 来查找搜索字符串在一行中出现的位置.

You could also use regular expressions, or String.indexOf() to find where in a line your search string appears.