Reading files with code value pairs

Question

I have a text file with about a hundred code value pairs [$code, Value].

For example:

Sample file

$codeA
valueOfA
$codeB
valueofB
.
.
.

These values need to be initiated into textFields, radioButtons, checkBoxes, etc over "several panels" contained within a main Controller panel. I switch between panels through a simple card layout.

I read through the lines and use if/else statements to get values for the fields, which isn't efficient. I was wondering if there is a better approach, a more elegant approach maybe.

 /*
 * read File
 */
private void readFile() {
 BufferedReader br = null;
 try {
 br = new BufferedReader(new FileReader(fileName));
 String line = null;
 while ((line = br.readLine()) != null) {
 if (line.equals("$codeA")) {
 panel1.txtFieldA.setText(br.readLine()));
 } else if (line.equals("$codeB")) {
 panel2.txtFieldB.setText(br.readLine()));
 }
 //.....
 //.....
 }
 } catch (IOException e) {
 e.printStackTrace();
 } finally {
 if (br != null) {
 try {
 br.close();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }
}

• Flown: I would suggest to create a mapping between a String and the textfield like ["$codeA" -> txtFieldA, ...] during the initialization process of the UI components. Then you can perform such things like: txtFields.get(line).setText(br.readLine())
• Phrancis: Please note, if you want to move this to Code Review site, make sure you include all the code to be reviewed, rather than having //..... sections. Otherwise, it may get closed as stub code.

Answer 1

Make a Map like this

Map<String, JTextField> map = new HashMap<>();
map.put("$codeA", panel1.txtFieldA);
map.put("$codeB", panel2.txtFieldB);

and change your loop like this

String code = null;
while ((code = br.readLine()) != null) {
 JTextField jtf = map.get(code);
 if (jtf != null)
 jtf.setText(br.readLine());
 else
 br.readLine();
}

• San Mor: Lets say, I have a group of radio buttons, check boxes. Can I just declare a hashmap of a generic object

Answer 2

I think I found a better solution. I welcome critique.

 Map<String, Operate> map = map = new HashMap<String, Operate>();
 map.put("$codeA", new TextFieldsOp(textField1));
 map.put("$codeB", new TextFieldsOp(textField2));
 map.put("$codeD", new RadBtnsOp(btnGroup));

Operate is an interface which is implemented by classes TextFieldsOp and RadBtnsOp.

public class TextFieldsOp implements Operate {
private JTextField txtF = null;
public TextFieldsOp(JTextField txtF) {
 this.txtF = txtF;
}
@Override
public void execute(String str) {
 txtF.setText(str);
 }
}

...

public class RadBtnsOp implements Operate {
ButtonGroup btnGroup;
public RadBtnsOp(ButtonGroup btnGroup) {
 this.btnGroup = btnGroup;
}
@Override
public void execute(String str) {
 //set Radio Buttons here
 }
}

...

 /*
 * read File
 */
private void readFile() {
 BufferedReader br = null;
 try {
 br = new BufferedReader(new FileReader(file));
 String code = null;
 while ((code = br.readLine()) != null) {
 Operate c = map.get(code);
 if (c != null) {
 c.execute(br.readLine());
 }
 }
 } catch (IOException e) {
 e.printStackTrace();
 } finally {
 if (br != null) {
 try {
 br.close();
 } catch (IOException e) {
 e.printStackTrace();
 }
 }
 }
}