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Java 运行程序时写入值_Java - Fatal编程技术网

Java 运行程序时写入值

Java 运行程序时写入值,java,Java,我想将一些数据写入.txt文件 public void writeToFile(String filename) { try { //Construct the BufferedWriter object bufferedWriter = new BufferedWriter(new FileWriter(filename)); //Start writing to the output stream buf

我想将一些数据写入.txt文件

     public void writeToFile(String filename) {

    try {

        //Construct the BufferedWriter object
        bufferedWriter = new BufferedWriter(new FileWriter(filename));

        //Start writing to the output stream
        bufferedWriter.write("first value : " + firstValue);
        bufferedWriter.newLine();

    } catch (FileNotFoundException ex) {
        ex.printStackTrace();
    } catch (IOException ex) {
        ex.printStackTrace();
    } finally {
        //Close the BufferedWriter
        try {

           if (bufferedWriter != null) {
               bufferedWriter.flush();
                bufferedWriter.close();
            }
        } catch (IOException ex) {
           ex.printStackTrace();
        }
    }
}
我使用这段代码,但问题是,它不断地覆盖第一行(我想)。 有人知道我如何解决这个问题吗? 我从串行端口读取了everey 50ms a值,不想写这个。(每个值都在单独的行中)

它应该写入值,直到我关闭程序

致以最诚挚的问候

试着换一行:

bufferedWriter = new BufferedWriter(new FileWriter(filename));
致:


我将以追加模式打开文件写入,它将在文件中添加内容,而不是覆盖它。

按如下方式打开写入程序:

bufferedWriter = new BufferedWriter(new FileWriter(filename, true));
这将打开要追加的文件。看

bufferedWriter = new BufferedWriter(new FileWriter(filename, true));