title: Error with writing to a file in Java
body: <p>I am getting the following errors. 
  Exception in thread "main" java.lang.NullPointerException at ReadFile.createDogs(ReadFile.java:41) at ReadFile.main(ReadFile.java:55)
  The file is opening to the desktop. I feel I am missing something very 
  simple. I have included the class file also. The error is specific to 
  dogOutput.println(dogInfo);</p>
  
  <p>Thank you.</p>
  
  <pre><code>    import java.io.*;
      import java.io.PrintWriter;
      public class ReadFile
      {
      private static Canine[] getCanine()
      {
  
      Canine[] canines= new Canine[5];
      canines[0]=new Canine("Thoedore", "Male", "Medium",  7, 50);
      canines[1]=new Canine("Magellan", "Male", "Medium",  5, 50);
      canines[2]=new Canine("Duffy", "Male", "Small",  10, 10);
      canines[3]=new Canine("Sammie", "Female", "Medium",  7, 65);
      canines[4]=new Canine("Snowball", "Male", "Small",  13, 17);
  
      return canines;
  
      }
  
      private static PrintWriter createFile(String fileName)
      {
          try{
              File listOfDogs = new File(fileName);
              PrintWriter  infoToWrite= new PrintWriter
                                         ( new BufferedWriter
                                              (new FileWriter(listOfDogs)));
             }
          catch (IOException e)
             {
              System.out.println(" An I/O Error Occurred.");
              System.exit(0);
  
             }
             return null;
      }
  
         private static void createDogs(Canine dog, PrintWriter dogOutput)
         {
          String dogInfo= dog.name + " " + dog.gender+ " " + dog.size +" ";
         dogInfo += Integer.toString(dog.age)+ " "+ 
           Double.toString(dog.weight);
  
          dogOutput.println(dogInfo);
  
          }
  
      public static void main (String[] args)
      {
  
         Canine[] canines= getCanine();
         System.out.println("Here1");
           PrintWriter dogOutput = 
            createFile("/Users/Teacher/Desktop/Dogs.text");
  
  
         for(Canine dogs: canines)
         {
             createDogs(dogs, dogOutput);
             System.out.println("Here5");
         }
  
         dogOutput.close();
  
      }
     private static class Canine extends Pet
     {
     public static final String type="Dog";
  
      public Canine()
      {
      super.type=this.type;
  
  
      }
  
      public Canine(String name, String gender, String size,  int age, double 
       weight)
      {
      super.type=this.type;
      super.name=name;
      super.gender=gender;
      super.size=size;
      super.age=age;
      super.weight=weight;
  
      }
  
  
      public static void setType(String word)
      {
  
  
      }
  
  
  
  
  
     }
  
  
      private static class Pet
      {
  
      public static String type;
      public static String color;
      public static String gender;
      public static String temperment;
      public static String food;
      public static int age;
      public static double weight;
      public static String name;
      public static String size;
  
  
      public Pet()
      {
      }
  
      public Pet(String type,String color,String gender,String temperment,
      String food,int age,double weight,String name,String size)
      {
          type=type;
          color=color;
          gender=gender;
          temperment=temperment;
          food=food;
          age=age;
          weight=weight;
          name=name;
          size=size;
  
      }
  
      public Pet(String name, String gender, String size,  int age, double 
       weight)
      {
          name=name;
          gender=gender;
              size=size;
              age=age;
              weight=weight;
      }
  
      public static String getType()
      {
          return type;
  
      }
  
      public static String getName()
      {
          return name;
  
      }
  
      public static String getSize()
      {
          return size;
  
      }
      public static String getColor()
      {
          return color;
  
      }
      public static String getTemperment()
      {
          return temperment;
  
      }
      public static String getFood()
      {
          return food;
  
      }
      public static String getGender()
      {
          return gender;
  
      }
      public static int getAge()
      {
          return age;
  
      }
  
      public static void setType(String word)
      {
          type=word;
  
      }
  
      public static void getName(String word)
      {
          name=word;
  
      }
  
      public static void setSize(String word)
      {
          size=word;
  
      }
      public static void setColor(String word)
      {
          color=word;
  
      }
      public static  void getTemperment(String word)
      {
          temperment=word;
  
      }
      public static void setFood(String word)
      {
          food=word;
  
      }
      public static void setGender(String word)
      {
          gender=word;
  
      }
      public static void setAge(int ageSet)
      {
          age=ageSet;
  
      }
  
  
      public static void setWeight(double weightSet)
      {
          weight=weightSet;
  
      }
      public static void setName(String NameSet)
      {
          name=NameSet;
  
      }
  
      public  String toString()
      {
          return ("Type "+type+"\n" +" Name "+name+"\n"+" Age "+age+"\n"+ 
     "Size "+ size+"\n"+" Gender "+gender+"\n"+" Weight "+weight);
  
        }
  
       }
  
  
  
      }
  </code></pre>