java替换文件内容

public static void writeToTxtByRandomAccessFile(File file, String str){
        RandomAccessFile randomAccessFile = null;
        try {
            randomAccessFile = new RandomAccessFile(file,"rw");
            long len = randomAccessFile.length();
            randomAccessFile.seek(len);
            randomAccessFile.writeBytes(new String(str.getBytes(),"iso8859-1")+"rn");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }catch (IOException e) {
            e.printStackTrace();
        }finally{
            try {
                randomAccessFile.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

传入要替换的文件路径和内容即可