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Having problem with Try-Catch block in a Java I/O program.

Answer 1

A:

Have a look at the java api

With some research you will find out why

... getText method is undefined

on your Strings.

But I would suggest you to use a IDE, even for homework.

HeDinges 2009-11-14 08:13:28

Answer 2

+1 A:

For all of the setText methods: you have local variables that override the class variables. Try this instead:

private void writeRecord() {

    String l_employeeName;
    Double l_hourlyRate;
    Integer l_employeeNumber, l_regularHours, l_overtimeHours;


 // this is where I am having errors. It is saying that the getText method is undefined
 // for each respective use (int, string, double). I am also getting error "The method
 // writeString(String) is undefined for the type DataOutputStream" and the same 
 // undefined errors for the setText for each respective use. 

    try {
        l_employeeName = String.parseString(employeeName.getText());
        l_employeeNumber = Integer.parseInt(employeeNumber.getText());
        l_hourlyRate = Double.parseDouble(hourlyRate.getText());
        l_regularHours = Integer.parseInt(regularHours.getText());
        l_overtimeHours = Integer.parseInt(overtimeHours.getText());
        ostream.writeString(l_employeeName);
        ostream.writeInt(l_employeeNumber);
        ostream.writeDouble(l_hourlyRate);
        ostream.writeInt(l_regularHours);
        ostream.writeInt(l_overtimeHours);
        employeeName.setText("");
        employeeNumber.setText("");
        hourlyRate.setText("");
        regularHours.setText("");
        overtimeHours.setText("");

For ostream.writeString: The documentation for DataOutputStream shows that there is no ostream.writeString. Try using ostream.writeChars .

Chip Uni 2009-11-14 08:19:25

The code works but it still gives me the error "The method parseString(String) is undefined for the type String" for the employeeName string. I will look over the info in the link that was posted. I am using Eclipse Galileo b/c that is what the instructor told us to get used to using (whereas he teaches using NetBeans) if that is what you were referring to.

Ryujin89 2009-11-14 08:34:58

Go take a look at the API doc for Integer.parseInt and Double.parseDouble. I suspect that you might not understand exactly what they're doing. Then ask yourself what you're trying to do with the non-existent String.parseString.

nojo 2009-11-14 14:24:36

Answer 3

A:

The problem is that you want to access the member variables but actually access the local variables. The names of the local variables actually hide your member variables! If you define a class like this

public class A {
  private int asdf = 0;

  public void blah() {
    String asdf = "Hello!";
    System.out.println(text);
  }

}

The program will print "Hello!" if you call "blah". This is because the local variable "text" hides the member of the same name. You have two options:

Choose different names like this

public class A {
  private int aNumber = 0;


  public void blah() {
    String asdf = "Hello!";
    System.out.println(aNumber);
  }


}

Use this to access the member like this

   public class A {
      private int asdf = 0;


  public void blah() {
    String asdf = "Hello!";
    System.out.println(this.asdf);
  }


}

Arne 2009-11-14 08:36:09

+1 for suggesting "this." - this makes the code least brittle.

Thorbjørn Ravn Andersen 2009-11-14 11:00:47

Answer 4

+1 A:

You made 3 basic errors

Your local variables in writeRecord() have the same name as the instance variables and thus are hiding them. Already indicated by Chip Uni + solution.
The String class has no function parseString(String). Check the javadoc (JDK API: String). Just remove that completely as getText() anyway returns a String.
DataOutputStream has no function writeString() use writeChars() instead

jitter 2009-11-14 10:28:31

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Having problem with Try-Catch block in a Java I/O program.

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