Write Hashset To Txt Using Filewriter

Mar 23, 2015

I am trying to write a hashset to a text file. Normally, I have no issues with writing to txt as it is simple for me. However, in this case I am absolutely clueless.

A bit of background about the class: it is a hashset of ComputerScientist objects with 2 fields; name, and field of research (and yes, I know what I put to fill up the HashSet does not count, I was only trying to test to see if I could get this to work).

I know the basic setup to use filewriter to save strings to a txt, but I am getting confused with the HashSet element of it.

import java.util.HashSet;
import java.io.FileWriter;
import java.io.IOException;
/**
* Write a description of class ComputerScientistSet here.
*/
public class ComputerScientistSet {
private HashSet<ComputerScientist> computerScientistSet;

[Code] .....

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Ive been trying to implement the Filewriter to my code. What I want is to have the textfield data written to a text field. Im thinking you have to specify the text field you want to have in the filewriter statement,I've done something like this, Ive used the try catch block.

if (source == jBPay) {
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[code]...

What I want is to have the textfield data written to a text file*Hi all, Ive been trying to implement the Filewriter to my code but I cant figure out what im doing wrong.What I want is to have the file data written to a text field. Im thinking you have to specify the text field you want to have in the filewriter statement.

if (source == jBPay) {
System.out.println("Pay");
{
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[code]...

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How to write a new file:

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import java.io.PrintWriter.*;
import acm.util.*;
import javax.swing.*;
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public void run() {

try {
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(I added the imports at top myself.) However, I am getting compiler errors for the lines: PrintWriter wr = new PrintWriter( new FileWriter ("hello.txt") ) , which says that the constructor PrintWriter( FileWriter ) is undefined, and
wr.close();, which says close() method is undefined.

Pretty sure the only real problem is that PrintWriter is not accepting the FileWriter as constructor, but I don't see why. I have tried this on machine with JRE 1.4 and it worked as expected, creating new file titled "hello.txt", prints line of "Hello world!" in that file, and saves it to the directory I picked in the dialog. But I can't get it to work on this machine that uses Compiler 1.6, Java Runtime v8u25.

I have also tried using just a string in the parameter for PrintWriter, such as PrintWriter wr = new PrintWriter ("hello.txt") , and from what I can tell by reading the java spec for java 8, this should work. [URL] .... But I get error message for that constructor as well.

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Harry Williams Software Engineering

Palbo Kastro Formal Languages

Alex W Advanced SE

James H Operating System

Harry Williams Theoretical Foundation

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Input:

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[Code] ....

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[code]....

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