30 replies to this topic

[PicklishDoorknob]

Very short beginning here.

import java.io.*;


public class FileReader {

	BufferedReader reader = new BufferedReader(new Reader());

}

It doesn't work giving a compiler error: Cannot instantiate the type Reader. :confused::confused::confused:

EDIT: Same with this:

import java.io.*;


public class FileWriter {

	BufferedWriter writer = new BufferedWriter(new Writer());

}

Cannot instantiate the type Writer.

[Animus]

just what exactly are you trying to make here?

[wim DC]

Reader and Writer are abstract classes, you need to create a concrete class which extend those.
For Reader:
BufferedReader, CharArrayReader, FilterReader, InputStreamReader, PipedReader, StringReader
For Writer:
BufferedWriter, CharArrayWriter, FilterWriter, OutputStreamWriter, PipedWriter, PrintWriter, StringWriter

[PicklishDoorknob]

So I've done this:

import java.io.*;


public abstract class FileWriter extends Writer{

	FileWriter() {

		BufferedWriter writer = new BufferedWriter(this);

	}

}

But now I can't use the constructor because the class is abstract! I don't want to change the methods so I can't override them. help?
Main class:

public class Begin {


	/**

	 * @param args

	 */

	public static void main(String[] args) {

		new GUI(); new FileReader(); new FileWriter();

	}


}

EDIT:
OK so I overrode[?] them and now I need to know how to delete characters (other than reading the whole file, deleting it, and making a new file without the character(s).

EDIT: AHH
I can't access writer and reader from my main class! (the ones created in the constructor!

OH WAIT never mind couldn't I just make somepublic methods in my other classes? Wait a minute I'm confused. :confused:

[Sinipull]

I have no idea, what you are trying to do, but here's an example how to instantiate one.

File file = new File("alphabet_soup.txt");
BufferedReader in = new BufferedReader(new FileReader(file));

[PicklishDoorknob]

Sinipull said:

I have no idea, what you are trying to do, but here's an example how to instantiate one.

File file = new File("alphabet_soup.txt");

BufferedReader in = new BufferedReader(new FileReader(file));

I did that an it gave an error. Time to update Java?

[Norm]

Quote

it gave an error.

When you get errors that you want help with, copy and paste them on the forum.

[PicklishDoorknob]

 error.png   9.06K   11 downloads

[Norm]

Can you post something that is readable?

To copy the contents of the command prompt window:
Click on Icon in upper left corner
Select Edit
Select 'Select All' - The selection will show
Click in upper left again
Select Edit and click 'Copy'

Paste here.

[PicklishDoorknob]

It's an image. Click it.

Anyway, the code:

import java.io.*;


public class FileReader {

	File file = new File("data.txt");

	BufferedReader in = new BufferedReader(new FileReader(file));

}

The errors:
The constructor BufferedReader(FileReader) is undefined.
Theconstructor FileReader(File) is undefined.

[Norm]

Thanks.

Compiles with no errors for me with jdk1.6.

What versions of software are you using to do your compiles?

[PicklishDoorknob]

Norm said:

Thanks.

Very helpful?