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Android Build a Blog Reader Android App Getting Data from the Web Getting JSON Data from an HTTP Request

Posted by Jos s
Jos s
Courses Plus Student 44 Points

Problem with compile error - responseData

Task:

Finally, set the 'responseData' String variable with the data in 'charArray'. Convert it using the String constructor that takes a char array as its parameter.

String responseData = "";

try {
    URL treehouseUrl = new URL("http://blog.teamtreehouse.com/api/get_recent_summary/?count=20");
    HttpURLConnection connection = (HttpURLConnection) treehouseUrl.openConnection();
    connection.connect();
    int responseCode = connection.getResponseCode();

    if (responseCode == HttpURLConnection.HTTP_OK) {

        // Code to read InputStream goes here!
       InputStream is = connection.getInputStream();
       Reader reader =  new InputStreamReader(is);
       char[] charArray = new char[connection.getContentLength()];
       reader.read(charArray);
       String responseData = new String(charArray);
    }
}
catch (MalformedURLException e) {
    Log.e(TAG, "MalformedURLException caught!", e);
}
catch (IOException e) {
    Log.e(TAG, "IOException caught!", e);
}

What's problem with this. Compiler says:  JavaTester.java:74: responseData is already defined in run()
       String responseData = new String(charArray);
              ^
1 error

2 Answers

Chris Shaw
Chris Shaw
26,676 Points
Chris Shaw
Chris Shaw
26,676 Points

Hi Jos,

This error is occurring because you're attempting to refine the variable responseData which you've already defined before the try/catch block, simply remove the String typecast from the try catch and it should work as expected.

responseData = new String(charArray);
Jos s
PLUS
Jos s
Courses Plus Student 44 Points
Jos s
Jos s
Courses Plus Student 44 Points

So the solution is to remove it out and place before or after in try/catch block ?

Chris Shaw
Chris Shaw
26,676 Points
Chris Shaw
Chris Shaw
26,676 Points

No, the try/catch block isn't the issue, the problem is you've already defined responseData outside of the try/catch block and have also attempted to define it again within the try/catch block which won't work as variables with the same name can only be defined once within the same scope.

Currently you have the below.

reader.read(charArray);
String responseData = new String(charArray);

Instead what you want is the following, I've shortened the code quite a bit but have retained the overall structure.

// Define the `responseData` variable
String responseData = "";

try {
    // Connection code here...

    if (responseCode == HttpURLConnection.HTTP_OK) {
        // Assign the response text to the already defined `responseData` variable
        responseData = new String(charArray);
    }
}
catch (MalformedURLException e) {
    Log.e(TAG, "MalformedURLException caught!", e);
}
catch (IOException e) {
    Log.e(TAG, "IOException caught!", e);
}

Hope that makes it's a little more clear.