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POInconsistent null pointer exceptions
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copied!<p>I am trying to read a .json file from the devices external directory.</p> <p>I have a class called ExternalFile which is used to read in a file and return the contents as a string.</p> <p>Here is the class:</p> <pre><code>public class ExternalFile { final String EXTERNAL_STORAGE = Evironment.getExternalStorageDirectory().toString(); final String FIRSTDROID_DIRECTORY = EXTERNAL_STORAGE + "/firstdroid/"; final String SALES_DIRECTORY = FIRSTDROID_DIRECTORY + "sales/"; final String REFERENCE_DIRECTORY = FIRSTDROID_DIRECTORY + "reference/"; public String readFile(String direcectory, String fileName) { BufferedReader br; StringBuilder sBuffer; File JSON; String line; String retVal = null; try { sBuffer = new StringBuilder(); JSON = new File(direcectory, fileName); br = new BufferedReader(new FileReader(JSON)); while ((line = br.readLine()) != null) { sBuffer.append(line); sBuffer.append('\n'); } retVal = sBuffer.toString(); Log.d("File Results: ", retVal); } catch (Exception e) { Log.e("readJSON", e.getMessage()); } return retVal; } </code></pre> <p>}</p> <p>When i use this class to read a "login.json" file, it works fine. However when I use the class to read a "contacts.json" file, eclipse warns: "Null pointer access: The variable readJSON can only be null at this location".</p> <pre><code> private void getContactNames() { // File jsonCustomers; // BufferedReader br= null; // StringBuilder sb = null; // String line; String result; ExternalFile readJSON = null; try { result = readJSON.readFile(REFERENCE_DIRECTORY, "contacts.json"); // pass through the json string readNames(result, "contact"); } catch (Exception e) { messageBox("getCustomerNames", e.toString()); } } </code></pre> <p>the only difference is that I pass in "contacts.json" instead of "login.json"</p>

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