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Thread: Error in Main

  1. #1
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    Question Error in Main

    Hello and thank you for your help in advance. I keep receiving the error as it is shown below and I can not figure out what is wrong with it as I have a comment marked out at line 16. My code is three classes that is suppose to return 50 state objects back to me when I run it. I am also to include a bubble sort(returns states in ascending order), sequential search(returns found/not found from search key state name) and binary search(returns found, not found, probes). Once again your help is appreciated.



    HTML Code:
    Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - cannot find symbol
      symbol:   class StateController
      location: class main.Main
    	at main.Main.main(Main.java:16)



    import java.io.*;
     
    public class Main {
     
        /**
         * @param args the command line arguments
         * 
         */
     
        public static void main(String[] args) throws IOException 
        {
            // Create an array of individual state objects to hold 50 items
            StateController myStateController;
            myStateController = new StateController(50);
     
            //call method to retrieve data and store in new array
            myStateController.loadData("States.Fall2014.txt");
     
            // display original array of states with headers
            myStateController.displayStates();
     
                // use bubble sort for state objects
                 myStateController.bubblesort();
     
                 myStateController.getCount();
     
                // contains search keys from file search
            myStateController.loadSearchKeys("State.Trans.txt");
     
              // Use binary search for alternate way to show results
                myStateController.binarySearch();
     
        }
     
        public Main() {
        }
     
    }// end Class Main



    public class State {
     
        private String stateName;
        private String stateCapital;
        private String stateAbbrev;
        private String stateRegion;
        private int statePopulation;
        private int regionNumber;
     
        /** 
        * @param name the name of the state
        * @param capital the capital of the state
        * @param abbrev the state's abbreviation
        * @param pop the population of the state
        * @param region the region of the state
        * @param regNum the region number of the state
        */
     
       public State (String name, String capital, String abbrev, String region,int pop, int regNum) 
        {
            stateName = name;
            stateCapital = capital;
            stateAbbrev = abbrev;
            stateRegion = region;
            statePopulation = pop;
            regionNumber = regNum;
     
        }//End State
     
       // Create getters for the six attributes
     
         /**
         * Returns the name of the state
         * @param None
         * @return stateName
         */
            public String getstateName()
            {
                return stateName;
            }
     
         /**
         * Returns state capital
         * @param None
         * @return stateCapital
         */
            public String getstateCapital()
            {
                return stateCapital;
            }
     
         /**
         * Returns state abbreviation
         * @param None
         * @return stateAbbrev
         */
            public String getstateAbbrev()
            {
                return stateAbbrev;
            }
     
     
         /**
         * Returns state region
         * @param None
         * @return stateRegion
         */
            public String getstateRegion()
            {
                return stateRegion;
            }
     
     
         /**
         * Returns region number
         * @param None
         * @return regionNumber
         */    
             public int getregionNumber()
            {
                return regionNumber;
            }
     
         /**
         * Returns statePopulation
         * @param None
         * @return statePopulation
         */     
            public int getstatePopulation()
            {
                return statePopulation;
            }
     
     
        /**
         * Data needed for the column headers
         * @return string
         */ 
        public String toString()
        {
            String str = String.format("%15s-%15s-%5s-%10s-%20s-%5s",
                stateName,stateCapital,stateAbbrev,stateRegion,regionNumber,statePopulation);
            return str;
        }//end toString
    }// end State class



    /**
     * Create class for state controller
     */
    public class StateController 
    {
        private State [] myStates;
        private int numStates = 0;
        private String[] searchKey = new String[14];
        private int numKeys;
        public int numSwap;   
     
     
     
    /**
     * Creates the Controller and array of state objects
     * @param maxSize 
     */
     
        public StateController(int maxSize)
        {
     
            myStates = new State[maxSize];
     
        }//end StateController
     
        public void loadData(String filename) throws IOException
        {
           FileInputStream fis1 = new FileInputStream("State.Fall2014.txt");
           BufferedReader br1 = new BufferedReader (new InputStreamReader(fis1));
           String name,capital,abbrev,region;
           int pop,regNum;  
     
           String inputString;
           inputString = br1.readLine();
     
           System.out.printf("%15s-%15s-%5s-%10s-%20s-%5s","Name","Capital","Abbrev",
                   "Population","Region","Region Number");
           System.out.println("==================================================================================================");
     
           while (inputString != null)
           {
               name = inputString.substring(0, 15).trim();
               capital=inputString.substring(15, 30).trim();
               abbrev=inputString.substring(30, 32).trim();
               region=inputString.substring(40, 55).trim();
               pop = Integer.parseInt(inputString.substring(32,40).trim());
               regNum = Integer.parseInt(inputString.substring(55,56).trim());
     
               myStates[numStates] = new State (name, capital, abbrev, region,pop, regNum);
               numStates++;
               inputString = br1.readLine();
           }
            br1.close();
        }
     
        public void displayStates()
        {
            int index;
            for(index = 0; index < numStates; index++)
            {
            System.out.println(myStates[index]);
        }//end for
    }//end displayStates
     
        public void bubbleSort()
        {
            int out,in;
            numSwap = 0;
            { 
            for (out = numStates - 1; out>1; out--)
                 for (in = 0; in<out; in++)
                 {
                     if (myStates[in].getStateName().compareTo(myStates[in +1].getStateName()) < 0)
                         swap (in, in +1);
                 }// end if(swap)
     
     
        }//end inner for loop
     
     
            System.out.println("Array of State Objects Sorted with A Bubble Sort");
            System.out.printf("%15s-%15s-%5s-%10s-%20s-%5s","Name","Capital","Abbrev",
                   "Population","Region","Region Number");
            System.out.println("==================================================================================================");
           displayStates();
        }//end bubble sort
     
        /**
         * //swap method to carry out the swap
         * @param one
         * @param two 
         */
        private void swap (int one, int two)
        {
            State name = myStates[one];
            myStates[one] = myStates[two];
            myStates[two] = name;
     
        }// end swap(int one, int two)
     
        public void getCount()
        {
            System.out.println("Number of swaps Using the Bubble sort on the Array of State Objects was: "+numSwap);
        }//end getCount()
     
        /**
         * reads input file
         * @param filename
         * @throws IOException 
         */
        public void loadSearchKeys(String filename) throws IOException
        {
            FileInputStream fis1 = new FileInputStream("State.Trans.txt");
            BufferedReader br1 = new BufferedReader(new InputStreamReader(fis1));
            int end;
            String key;
     
            String inputString;
            inputString = br1.readLine();
     
            while(inputString !=null)
            {
                end = Math.min(14, inputString.length());
                key = inputString.substring(0,end);
               searchKey[numKeys] = key;
               numKeys++;
               inputString = br1.readLine();
     
            }//end while
            br1.close();
        }//end load searchkeys
     
        /**
         * displays result from search keys
         */
        public void displayKeys()
        {
            for(int index = 0; index < numKeys; index++)
            {
                System.out.println(searchKey[index]);
            }//end for        
        }//end display keys
     
        /**
         * Create a sequential search that uses "State.Trans.txt" file
         * @param searchKey
         * @return 
         */
      public String seqSearch(String searchKey) {
            int probe;
            String answer;
     
            for (probe = 0; probe < numStates; probe++) //for each object in array
            {
                if (myStates[probe].getName().compareToIgnoreCase(searchKey) == 0) //if found searchKey
                {
                    probe++;
                    break;                    //exit before end of loop
                }//end if
            }//end for
            if (probe == numStates) //searched all array elements?
            {
                probe++;
                answer = ("            X    ");      //if yes, can't find
            }//end if
            else {
                probe++;
                answer = ("  X              ");          //if no, found searchKey
            }//end else
     
            String format = "%1$-15s %2$-20s %3$6d"; //to align under column headers
            String result = String.format(format, searchKey, answer, probe);
            //format result
     
            return result;
     
      }//end sequential search
     
      /**
       * Create Binary search
       * @param searchKey
       * @return 
       */
     
      public String binarySearch(String searchKey) {
            int curIn;
            int probe = 0, lowerBound = 0, upperBound = numStates - 1;
            String format = "%1$-15s %2$-20s %3$6d";
            //to align results under column headers
            String answer, result;
     
            while (true) {
                curIn = (lowerBound + upperBound) / 2;//set curIn to middle of array
     
                if (myStates[curIn].getName().compareToIgnoreCase(searchKey) == 0) //found searchKey?
                {
                    probe++;
                    answer = ("  X              ");
                    result = String.format(format, searchKey, answer, probe);
                    //format search results
                    return result;
                }//end if
                else if (lowerBound > upperBound)//max probes reached?
                {
                    answer = ("            X    ");//can't find
                    result = String.format(format, searchKey, answer, probe);
                    //format search results
                    return result;
                }//end else if
                else {
                    probe++;
                    if (myStates[curIn].getName().compareToIgnoreCase(searchKey) < 0) //does curIn come before searchKey?
                    {
                        lowerBound = curIn + 1;//check upper half
                    }//end if 
                    else {
                        upperBound = curIn - 1;//check lower half
                    }//end else
                }//end else
            }//end while
        }//end binarySearch()
    }//end state controller


  2. #2
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    Default Re: Error in Main

    The error message is quite clear, it says it can not find a class called StateController.

  3. #3
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    Default Re: Error in Main

    ok I figured out that problem but now its a new set of errors

    Exception in thread "main" java.io.FileNotFoundException: State.Fall2014.txt (The system cannot find the file specified)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(FileInputStream.jav a:131)
    at java.io.FileInputStream.<init>(FileInputStream.jav a:87)
    at main.StateController.loadData(StateController.java :38)
    at main.Main.main(Main.java:26)

  4. #4
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    Default Re: Error in Main

    The system cannot find the file specified. Is there anything unclear?

  5. #5
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    Default Re: Error in Main

    the IDE highlights:
    myStateController.binarySearch();

  6. #6
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    Default Re: Error in Main

    But the error message says something different. The IDE might highlight that because there might be a compile-time problem. However, your application crashed because of a runtime-problem, namely an IOException.
    You attempted to load a file which the system was not able to find.

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