I got a null pointer exeption error on Attempt to invoke virtual method void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference.  public class MainActivity {     TextView servingqueue; }   This is onCreate      DatabaseReference mRootRef = FirebaseDatabase.getInstance().getReference(); DatabaseReference mServingQueue = mRootRef.child("ServingQueue");  servingqueue = (TextView) findViewById(R.id.queueServing);  mServingQueue.addValueEventListener(new ValueEventListener() {     @Override     public void onDataChange(DataSnapshot dataSnapshot) {         Double number = dataSnapshot.getValue(Double.class);         servingqueue.setText(String.valueOf(number));     }      @Override     public void onCancelled(DatabaseError databaseError) {      }   The error appeared right on   servingqueue.setText(String.valueOf(number));   It just does not want to pass the value from Firebase to my textview. I get force close from my app upon loading the activity.
129
What are Null Pointer Exceptions (java.lang.NullPointerException) and what causes them?  What methods/tools can be used to determine the cause so that you stop the exception from causing the program to terminate prematurely?
95979
There were custom validation error(s) encountered while saving the affected record(s). The first validation error encountered was:      Apex trigger updatequotestatus caused an unexpected exception, contact your administrator: updatequotestatus: execution of AfterInsert caused by: System.NullPointerException: Attempt to de-reference a null object: Trigger.updatequotestatus line 5, column 1.   Error Occured at Line:     if((t.what.getsobjecttype() == quote__c.sobjecttype) &amp;&amp; (t.subject.substring(0,5) == 'Email')  trigger updatequotestatus on task (after insert, after update){     Set&lt;Id&gt; quoteIds = new Set&lt;Id&gt;();     List&lt;quote__c&gt; quotes = new List&lt;quote__c&gt;();      for(task t:trigger.new){         if(t.whatId!=null){             if((t.what.getsobjecttype() == quote__c.sobjecttype) &amp;&amp; (t.subject.substring(0,5) == 'Email')){                 quoteIds.add(t.whatId);             }         }     }      for(quote__c q:[select StageName__c from quote__c where Id IN : quoteIds]){         quote__c qt = new quote__c();         qt.Id = q.Id;         qt.StageName__c = 'Proposal Sent';         quotes.add(qt);     }      if(quotes.size()&gt;0){         update quotes;     } }
77120
I am trying to implement  and below is my code and debug log - any help is appreciated.  Http httpProtocol = new Http();    HttpRequest request = new HttpRequest(); request.setHeader('Content-Type', 'application/json;'); request.setEndPoint('https://test.salesforce.com/services/oauth2/token'); request.setMethod('POST'); String strbody = '{"grant_type":"Password", "password":"MY PASSWORD + TOKEN", "username":"SANDBOX USER NAME",  "client_secret":"secret",   "client_id":"Client id from remote setttings"}'; request.setBody(strbody); HttpResponse response = httpProtocol.send(request); String jsonInput = response.getBody(); system.debug('jsonInput===&gt;'+jsonInput);   Debug log -   15:55:38.068 (68324000)|SYSTEM_METHOD_ENTRY|[5]|System.HttpRequest.setMethod(String) 15:55:38.068 (68346000)|SYSTEM_METHOD_EXIT|[5]|System.HttpRequest.setMethod(String) 15:55:38.068 (68350000)|STATEMENT_EXECUTE|[6] 15:55:38.068 (68356000)|HEAP_ALLOCATE|[6]|Bytes:357 15:55:38.068 (68381000)|VARIABLE_ASSIGNMENT|[6]|strbody|"{\"grant_type\":\"Passw (337 more) ..." 15:55:38.068 (68387000)|STATEMENT_EXECUTE|[7] 15:55:38.068 (68407000)|SYSTEM_METHOD_ENTRY|[7]|System.HttpRequest.setBody(String) 15:55:38.068 (68440000)|SYSTEM_METHOD_EXIT|[7]|System.HttpRequest.setBody(String) 15:55:38.068 (68445000)|STATEMENT_EXECUTE|[8] 15:55:38.068 (68478000)|SYSTEM_METHOD_ENTRY|[8]|System.Http.send(APEX_OBJECT) 15:55:38.068 (68568000)|CALLOUT_REQUEST|[8]|System.HttpRequest[Endpoint=https://test.salesforce.com/services/oauth2/token, Method=POST] 15:55:38.483 (483258000)|HEAP_ALLOCATE|[EXTERNAL]|Bytes:219 15:55:38.483 (483399000)|CALLOUT_RESPONSE|[8]|System.HttpResponse[Status=Bad Request, StatusCode=400] 15:55:38.483 (483424000)|HEAP_ALLOCATE|[8]|Bytes:96 15:55:38.483 (483444000)|SYSTEM_METHOD_EXIT|[8]|System.Http.send(APEX_OBJECT) 15:55:38.483 (483615000)|VARIABLE_ASSIGNMENT|[8]|response|"System.HttpResponse[Status=Bad Request, StatusCode=400]"|0x1b22c3f1 15:55:38.483 (483627000)|STATEMENT_EXECUTE|[9] 15:55:38.483 (483666000)|SYSTEM_METHOD_ENTRY|[9]|System.HttpResponse.getBody() 15:55:38.483 (483742000)|HEAP_ALLOCATE|[9]|Bytes:81 15:55:38.483 (483751000)|SYSTEM_METHOD_EXIT|[9]|System.HttpResponse.getBody() 15:55:38.483 (483780000)|VARIABLE_ASSIGNMENT|[9]|jsonInput|"{\"error\":\"unsupporte (61 more) ..." 15:55:38.483 (483786000)|STATEMENT_EXECUTE|[10] 15:55:38.483 (483794000)|HEAP_ALLOCATE|[10]|Bytes:13 15:55:38.483 (483980000)|HEAP_ALLOCATE|[10]|Bytes:94 15:55:38.483 (483999000)|SYSTEM_METHOD_ENTRY|[10]|System.debug(ANY) 15:55:38.484 (484025000)|USER_DEBUG|[10]|DEBUG|jsonInput===&gt;{"error":"unsupported_grant_type","error_description":"grant type not supported"}
7576
I have a lookup to a custom object called Project on my Opportunity object. I am trying to write a trigger that updates an Active, Awarded, and Title on the Project object whenever the Active, Awarded, or Title field is updated on Opportunity based some on more logic that isn't in my code below. This is my first trigger and needing a little help due to a NullPointerException where I try to set Project__r.Active__c = true. Any thoughts?      trigger ProjectFieldsTrigger on Opportunity (before insert, before update) {       //List&lt;Opportunity&gt; opp = [SELECT Name, Active__c, Funded__c, Title__c, Project__r.Name, Project__r.Active__c, Project__r.Awarded__c      //  FROM Opportunity WHERE Id IN :Trigger.New];      for(Opportunity o: Trigger.New){          if(o.Project__c != null){              if(o.Active__c == 'Y'){                 o.Project__r.Active__c = true;             }      }  }
7898
The StackExchange app crashes for me on every start when I click a link in the browser. It seems (based on the StackTrace) that the url parser causes a null pointer exception. I'm using 0.1.90.
16290
This is a canonical question and answer developed by the community to help address common questions. If you've been directed here, or your question has been closed as a duplicate, please look through the resources here and use them to shape more specific questions. To browse all canonical questions and answers, navigate to the  tag. This question and answer is owned by the community! If you can improve it and make it more useful, you're welcome to edit it. I am building a trigger, a unit test, or other Apex code. I'm working with sObject records, and trying to access related record information. For example, I might have a structure like this: Account a = new Account(Name = 'Test'); insert a;  Opportunity o = new Opportunity(Name = 'Donation', AccountId = a.Id); insert o;  System.assertEquals(o.Account.Name, 'Test', 'Correct Account associated'); // Assertion fails!  Or, in a trigger, I might be aiming for something like this: trigger ContactTrigger on Contact (after insert) {     for (Contact c : Trigger.new) {         if (c.Account.Name == 'Test') {             // Take some action here         }      } }  Why doesn't this work? Why am I getting null values, or NullPointerExceptions?
49085
I am facing difficulty in passing parameters to apex method from test method. In apex method, I am getting parameters from my VF page. Example of Apex Method: public PageReference create_contact()  {         String callfrom = System.currentPageReference().getParameters().get('callfrom');                  Contact newCon = new Contact(lastname = 'Anonymous', phone = callfrom);           insert newCon;                  return null; }  My Test method: static testMethod void testmatchingcontactController() {         test.startTest();         matching_contacts mc = new matching_contacts();         mc.create_contact();         test.stopTest(); }  On running test method, I get an error that &quot;Argument cannot be null&quot; because the parameter callfrom in apex code is provided by Visualforce page in application. I don't know how can I pass it from test method. Please help if you know solution to this problem.
18236
Steps to Reproduce   Tap faster on the code. or Tap once on a huge code.   but happens only when  setupForGeneric() is called, might be a bug related to   private void setupForCode()   { String str = getIntent().getStringExtra("com.stackexchange.marvin:code_block"); PrettyWebView localPrettyWebView = (PrettyWebView)findViewById(R.id.code); localPrettyWebView.setPostBody("&lt;pre&gt;&lt;code&gt;" + TextUtils.htmlEncode(str) + "&lt;/pre&gt;&lt;/code&gt;", false); localPrettyWebView.setBackgroundColor("#eeeeee"); }  private void setupForGeneric() { String str = getIntent().getStringExtra("com.stackexchange.marvin:web_url"); PrettyWebView localPrettyWebView = (PrettyWebView)findViewById(R.id.code); localPrettyWebView.getSettings().setBuiltInZoomControls(true); localPrettyWebView.getSettings().setLoadWithOverviewMode(true); localPrettyWebView.getSettings().setUseWideViewPort(true); localPrettyWebView.loadUrl(str); localPrettyWebView.setBackgroundColor("#eeeeee"); }   Log  09-05 03:54:30.312: E/AndroidRuntime(26264): FATAL EXCEPTION: WebViewCoreThread  09-05 03:09:39.522: E/Crittercism(18318): java.lang.NullPointerException: [v0.1.22]  09-05 03:09:39.522: E/Crittercism(18318):   at android.content.ComponentName.&lt;init&gt;(ComponentName.java:75) 09-05 03:09:39.522: E/Crittercism(18318):   at android.content.Intent.&lt;init&gt;(Intent.java:3156) 09-05 03:09:39.522: E/Crittercism(18318):   at com.stackexchange.marvin.ui.ViewPopupActivity.showCode(ViewPopupActivity.java:25) 09-05 03:09:39.522: E/Crittercism(18318):   at com.stackexchange.marvin.ui.question.QuestionFragment$1.onCodeClicked(QuestionFragment.java:67) 09-05 03:09:39.522: E/Crittercism(18318):   at com.stackexchange.marvin.ui.common.PrettyWebView$WebAppInterface.codeClicked(PrettyWebView.java:197) 09-05 03:09:39.522: E/Crittercism(18318):   at android.webkit.WebViewCore.nativeTouchUp(Native Method) 09-05 03:09:39.522: E/Crittercism(18318):   at android.webkit.WebViewCore.nativeTouchUp(Native Method) 09-05 03:09:39.522: E/Crittercism(18318):   at android.webkit.WebViewCore.access$4000(WebViewCore.java:59) 09-05 03:09:39.522: E/Crittercism(18318):   at android.webkit.WebViewCore$EventHub$1.handleMessage(WebViewCore.java:1449) 09-05 03:09:39.522: E/Crittercism(18318):   at android.os.Handler.dispatchMessage(Handler.java:99) 09-05 03:09:39.522: E/Crittercism(18318):   at android.os.Looper.loop(Looper.java:137) 09-05 03:09:39.522: E/Crittercism(18318):   at android.webkit.WebViewCore$WebCoreThread.run(WebViewCore.java:790) 09-05 03:09:39.522: E/Crittercism(18318):   at java.lang.Thread.run(Thread.java:856)
110820
I'm currently making a callout to a 3rd party vendor and I'm getting a huge response. What is currently messing me up is this section:   "MessageSeq":13,"Description":"config file: config-qa1.txt\"","MessageTS":"2014-02-17T14:46:58","MessageLevel":4,"IsSystemMessage":false   As you can see here, the portion at the end of the Description value is ended with backslash double quote. If I attempt to parse this via the JSONParser I get an exception. Does anyone have an recommendations on how to resolve this?  Exception Message:  System.JSONException: Unexpected character ('"' (code 34)): was expecting comma to separate OBJECT entries at [line:1, column:3699]  Updated with sample Code   public class ResponseWrapper{     // fields from JSON to auto map     public Integer messageSeq;     public String Description;     public String messageTS;     public Integer messageLevel;     public Boolean isSystemMessage;     // parsing fields     private ResponseWrapper theResponse;     private JSONParser parser;      public void parse(String jsonString){         parser = JSON.createParser(jsonString);         parseJSON();     }      private void parseJSON(){            while (parser.nextToken() != null) {             if (parser.getCurrentToken() == JSONToken.START_OBJECT) {                 theResponse = (ResponseWrapper)parser.readValueAs(ResponseWrapper.class);                            }         }     } }  String responseString = '{"MessageSeq":13,"Description":"config file: config-qa1.txt\"","MessageTS":"2014-02-17T14:46:58","MessageLevel":4,"IsSystemMessage":false}'; system.debug('\n\nBEFORE\n' + responseString); ****Place code in here to test such as ReplaceALL*** ResponseWrapper parser = new ResponseWrapper(); parser.parse(responseString);
8224
Since many users are facing the NullReferenceException: Object reference not set to an instance of an object error in Unity, I thought that it would be a good idea to gather from multiple source some explanation and ways to fix this error.  Symptoms I am getting the error below appearing in my console, what does it mean and how do I fix it?  NullReferenceException: Object reference not set to an instance of an object
86546
I have been trying to integrate Google Shortener API into my salesforce org. I wrote a class to make the call out, but am having difficulty bringing the value back into the record. I have a custom object called "referral_advocate__c" with a field called "Short_URL__c". Anytime the field "unique_ID__c" has a value, I am wanting to send this value with a static URL to google shortener and then save the response value to "referral_advocate__c.short_URL__c" on the record. This is the class to make the call out:  public class URLshort {  final string urls = 'https://www.myurl.com'; referral_advocate__c adv = new referral_advocate__c();  @future(callout = true) public static void URLshortner() {      HttpRequest req = new HttpRequest();     HttpResponse res = new HttpResponse();     Http http = new Http();      req.setEndpoint('https://www.googleapis.com/urlshortener/v1/url?key=myapikey');     req.setMethod('POST');     req.setHeader('Content-Type','application/json');            req.setBody('{"longUrl":+urls + adv.unique_reference_number_c}');       try {         res = http.send(req);         System.debug(res.getBody());     } catch(System.CalloutException e) {         System.debug('Callout error: '+ e);         System.debug(res.toString());     }   }  }   The after insert trigger on "referral_advocate__c" I wrote is not firing correctly. How do I return the results from this class and update the field "short_URL__C" with the returned value from a trigger?
14635
private string? typeOfContract {   get { return (string?)ViewState["typeOfContract"]; }   set { ViewState["typeOfContract"] = value; } }   Later in the code I use it like this:  typeOfContract = Request.QueryString["type"];   I am getting the following error at the declaration of typeOfContract line stating:     The type 'string' must be a non-nullable value type in order to use   it as parameter 'T' in the generic type or method   'System.Nullable&lt;T>'   Any ideas? Basically, I want to make sure that "type" exists in the QueryString before performing an action.
34848
I used to use the implicit call of toString when wanting some debug info about an object, because in case of the object is null it does not throw an Exception.  For instance:    System.out.println("obj: "+obj);   instead of:  System.out.println("obj: "+obj.toString());   Is there any difference apart from the null case? Can the latter case work, when the former does not?  Edit: What exactly is done, in case of the implicit call?
80203
This error should be a simple one but I cant seem to make it work. The problem lies in the fact that this very same code works earlier in the program. I don's see any reason for it to be sending an error on this instance and not the four previous ones. Reference the code below, and feel free to provide any criticism you may have as it should make me better. If it matters, I am using Sharp Develop 2.2.  Here is an example of the code that works:  void calc2Click(object sender, EventArgs e) {     if (!String.IsNullOrEmpty(tb2_fla.Text) &amp; String.IsNullOrEmpty(tb2_e.Text) | String.IsNullOrEmpty(tb2_fla.Text) &amp; String.IsNullOrEmpty(tb2_e.Text) | String.IsNullOrEmpty(tb2_e.Text))     {         MessageBox.Show("Enter either kVA and Voltage or FLA and Voltage", "Invalid Data Entry", MessageBoxButtons.OK);     }                 if (!String.IsNullOrEmpty(tb2_kva.Text) &amp; !String.IsNullOrEmpty(tb2_e.Text))     {              decimal x, y, z;             x = decimal.Parse(tb2_kva.Text);                   y = decimal.Parse(tb2_e.Text);             z = (x * 1000) / (1.732050808m * y); //the m at the end of the decimal allows for the multiplication of decimals                 tb2_fla.Text = z.ToString();             tb2_fla.Text = Math.Round(z,2).ToString();     }         else     {         if (!String.IsNullOrEmpty(tb2_fla.Text) &amp; !String.IsNullOrEmpty(tb2_e.Text))     {              decimal x, y, z;             x = decimal.Parse(tb2_fla.Text);                   y = decimal.Parse(tb2_e.Text);             z = (x * y * 1.732050808m) / 1000; //the m at the end of the decimal allows for the multiplication of decimals               tb2_kva.Text = Math.Round(z,2).ToString();      }   Here is the example of the code that sends the error in the subject line of this post:  void Calc4Click(object sender, EventArgs e) {         if (!String.IsNullOrEmpty(tb4_fla.Text) &amp;&amp; String.IsNullOrEmpty(tb4_e.Text) || String.IsNullOrEmpty(tb4_kw.Text) &amp; String.IsNullOrEmpty(tb4_e.Text) || String.IsNullOrEmpty(tb4_e.Text))         {   //If values are entered improperly, the following message box will appear         MessageBox.Show("Enter either FLA and Voltage or kW and Voltage", "Invalid Data Entry", MessageBoxButtons.OK);         }              if (!String.IsNullOrEmpty(tb4_fla.Text)&amp;&amp; !String.IsNullOrEmpty(tb4_e.Text)&amp;&amp; String.IsNullOrEmpty(tb4_kw.Text))         {//If the user eneters FLA and Voltage calculate for kW              decimal x, y, z;             x = decimal.Parse(tb4_fla.Text);             y = decimal.Parse(tb4_e.Text);             z = (x*y)*(.8 * 1.732050808m);             tb4_kw.Text = Math.Round(z,0).ToString();          }                         if (!String.IsNullOrEmpty(tb4_kw.Text) &amp;&amp; !String.IsNullOrEmpty(tb4_e.Text) &amp;&amp; String.IsNullOrEmpty(tb4_fla.Text))         {;//If the user enters kW and Voltage calculate for FLA             decimal x, y, z;             x = decimal.Parse(tb4_kw.Text);             y = decimal.Parse(tb4_e.Text);             z = (1000 * x)/(y * 1.732050808m)* .8;             tb4_fla.Text = Math.Round(z,0).ToString();         }      }   I appreciate any help that I can get.  Thank you.
23909
Looking for reviewers to suggest optimization and improvements, and to evaluate coding practices.  final class Variables {     private final int x;     private final int y;      Variables(int x2, int y2) {         this.x = x2;         this.y = y2;     }      public int getX() {         return x;     }      public int getY() {         return y;     }      @Override public String toString()  {          return "x = " + x + " y = " + y;     } }  public final class FindMissing {      private FindMissing() {};      /**  * Takes an input a sorted array with two variables that repeat in the  * range. Remaining variable are consecutive. and returns two variables that repeats  *   * eg: for a range of 1,2,3,4, a valid input is [1, 4], [1, 3] etc.  *   * @param a : the sorted array.  */ /*  * Why is start needed ?  * If start is not given then if a1 is empty how do we know if missing numbers were  * [1, 2] or [4, 5] ??.   */ public static Variables sortedConsecutiveTwoMissing (int[] a, int startOfRange) {     if (a == null) throw new NullPointerException("a1 cannot be null. ");      int low = startOfRange;     // calculating the highest value of the range. it needs to be 2 more than length since all elememts are consecutive.     int high = startOfRange + (a.length - 1) + 2;      int i = 0;     boolean foundX = false;     int x = 0;       while (i &lt; a.length) {         if (a[i] != low) {             if (foundX) {                 return new Variables(x, low);             } else {                 x = low;                 foundX = true;             }         } else {             i++;         }         low++;     }      return new Variables(x, high);  }  public static void main(String[] args) {         // unsortedConsecutiveTwoMissing         int[] a6 = {1, 4};         System.out.println("Expected 2 and 3, Actual " + sortedConsecutiveTwoMissing(a6, 1));         // unsortedConsecutiveTwoMissing         int[] a7 = {-4, -1};         System.out.println("Expected -3 and -2, Actual " + sortedConsecutiveTwoMissing(a7, -4));         int[] a8 = {-4, -3, -2, -1};         System.out.println("Expected 0 and 1, Actual " + sortedConsecutiveTwoMissing(a8, -4));         int[] a9 = {5};         System.out.println("Expected 4 and 6, Actual " + sortedConsecutiveTwoMissing(a9, 4));         }      }
78597
I keep getting the System.NullPointerException: Attempt to de-reference a null object on my trigger at line 21. I've attempted to add != null to that line and I get an error too. Please see the code below.  trigger UpdateDMAAccount on Account (before insert, before update) { //get set of Postal Codes from leads to be inserted or updated Set&lt;String&gt; BillingpostalCodes = new Set&lt;String&gt;(); for(Account l : trigger.new){ if(l.BillingPostalCode != null){     BillingpostalCodes.add(l.BillingPostalCode);  } } if(BillingpostalCodes.size() &gt; 0){ //create Map of custom object records with Name (PostalCode) as key Map&lt;String,DMA_Value__c&gt; validBillingPostalCode = new Map&lt;String,DMA_Value__c&gt;(); for(DMA_Value__c obj : [SELECT Id, Name, DMA_Value__c FROM DMA_Value__c WHERE Name IN :BillingpostalCodes]){     validBillingPostalCode.put(obj.Name,obj); } for(Account l : trigger.new){     if((Trigger.isInsert || trigger.oldMap.get(l.Id).BillingPostalCode != l.BillingPostalCode) &amp;&amp; validBillingPostalCode.containsKey(l.BillingPostalCode)){          l.DMA__c = validBillingPostalCode.get(l.BillingPostalCode).DMA_Value__c;     }     else if(trigger.oldMap.get(l.Id).BillingPostalCode != NULL || l.BillingPostalCode &amp;&amp; !validBillingPostalCode.containsKey(l.BillingPostalCode)){         //blank value if new PostalCode does not match a record in the Map         l.DMA__c = Null;     }   }  } }
37422
I'm getting this error every few days. I won't see the error for a few days then I'll get a flurry of 20 or so all with in a minute or so.  I've been very thorough going throw my code so that I'm using this basic setup for my DB access.  try {   myConnection.Open();   mySqlDataAdapter.Fill(myDataTable);   myConnection.Close(); } Catch (Exception err) {   if (myConnection.State != ConnectionState.Closed) myConnection.Close();   throw err; }   The way I understand it this should execute my queries and immediately release the connection back to the pool but if something goes wrong with the query then I catch the excpetion close my connection then throw the error up, which eventually gets trapped at the application level and logs and emails me the error.  Even using this throughout my code I'm still running across the issue. What can I do to diagnose the root cause of the issue?