java - 尝试显示创建的输出文件

Question

所以我将一个文件传递给文件编写器，然后传递给打印编写器。然而，根据我的分配指令，我应该打印这些变量，我使用父类(super class)中的 toString 方法传递给 printwriter。这是一项作业，因此规则非常明确，说明教师希望输出如何。

 System.out.print("Please enter a file name: ");
    fileName = input.next();
    File fw = new File(fileName + ".txt");       

 AccountWithException acctException = new AccountWithException(fullName, balance, id, RATE);

 System.out.println(acctException.toString()); <---This works


 // pass object to printwriter and pw to write to the file
        pw = new PrintWriter(fw);
        // print to created file
        pw.println(firstName);
        pw.println(lastName);
        pw.println(balance);
        pw.println(id);
        pw.println(RATE);
        System.out.println(pw.toString());  <---Doesn't work. Only prints location and im supposed to somehow use the overloaded toString method to output the data within the file (i guess after its written)

Answer 1

你实际上已经给出了自己的解决方案，但你需要这样的东西 -

pw = new PrintWriter(fw);
try {
  // print to created file
  // pw.println(firstName);
  // pw.println(lastName);
  // pw.println(balance);
  // pw.println(id);
  // pw.println(RATE);
  pw.println(acctException.toString()); // <-- Since 
                    // System.out.println(acctException.toString()); works!
} finally {
  pw.close(); // <-- Always close()!
}