Question

1.

Write a public Java class called WriteFile which opens an empty file called letters.dat. This program will read a String array called letters and write each word onto a new line in the file. The method should include an appropriate throws clause and should be defined within a class called TFEditor.

The string should contain the following words:
{“how”, “now”, “brown”, “cow”}

Answer 1

Here are the 2 classes you will be needing - TextFileEditior.java and WriteFile.java.

You need to run the WriteFile.java.

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import java.io.File;
import java.io.FileWriter;
import java.io.IOException;

public class TextFileEditor {

    final private String fileName;

    public TextFileEditor() {
        this.fileName = "letters.dat";
    }

    public void writeToFile(String[] words) throws IOException {

        FileWriter writer = new FileWriter(new File(fileName));
        if (words == null || words.length == 0) throw new IllegalArgumentException("String array empty or null.");

        for (String word : words) {
            writer.write(word + "\r\n");
        }
        writer.flush();
        writer.close();

        System.out.println("File: " + fileName + " updated sucessfully.");

    }


}

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import java.io.IOException;

public class WriteFile {

    public static void main(String[] args) {

        String words[] = {"how", "now", "brown", "cow"};

        TextFileEditor editor = new TextFileEditor();

        try {
            editor.writeToFile(words);

        } catch (IOException e) {
            System.out.println("Error: File not found.");
        } catch (IllegalArgumentException e) {
            System.out.println(e.getMessage());
        }

    }
}

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