Scanning text file and inserting contents into array

[jmwalloh]

Hi, am trying to read a text file using scanner in java and inserting the contents
into two arrays. One is 1D and the other is 2D.The content of the text file is as
follows:

Nancy -1.290 36.820
Mom -4.040 39.660
Nelly -0.280 36.070
Kim -0.090 34.750
Elly 0.52 35.270
Tom -1.040 37.090
Ron -1.140 36.960
Kelly 1.030 34.990
Oscar 0.290 34.730

Here is my code sample which is'nt working:

import java.io.File;
    import java.io.FileReader;
    import java.util.Scanner;
    
     
    public class Names {
        public static void main(String[] args) throws Exception {
                    
            File file = null;
            FileReader fr = null;
            Scanner sc = null;
            
            int count = 0;
            int count2 = 0;
            String name[] = new String[25];
            float codes[][] = new float[25][2];
     
            try     {
                
                file = new File("namedata.txt");
                fr = new FileReader(file);           
                sc = new Scanner(fr);
                
                while(sc.hasNext()){
                	 
                	 name[count] = sc.next();
                	 codes[count][count2] = sc.nextFloat();
                	 codes[count][(count2+1)] = sc.nextFloat();
                	 count++;
                	 count2 = 0; //reset count2
                	System.out.println("Names = "+name[count]+"\n");
                }
            }catch (Exception ex) {
        	ex.printStackTrace();
        	}finally {
              fr.close();
              sc.close();
          } 
        }
    }

Any help or suggestions are highly welcomed.

[iluxa]

float codes[][] = new float[25][2];

is not legit.

instead, you need to do

float codes [][] = new float [25][];

for (int i = 0; i < 25; i ++) {
  codes [i] = new float [2];
}

[Eranga]

Static allocations can cause lots of issues in runtime. For an example if your file content is more than 25 lines, then how can you read them all?

[Eranga]

float codes[][] = new float[25][2];

is not legit.

instead, you need to do

float codes [][] = new float [25][];

for (int i = 0; i < 25; i ++) {
  codes [i] = new float [2];
}

So what you are going to solve with this, it's better if you ca explain it. Otherwise OP may confused. :)

[mlad]

float codes[][] = new float[25][2];

is not legit.

Can I ask why this isn't legit?

I have a piece of code that uses

public static int[][] cache = new int[numBlocks][blockSize];

and it works exactly as I want. Your replacement code seems to make a 2D array but give the second dimension no value, then populate the first column with new Arrays (suggesting you don't need the second dimension at all?). I would just like to understand better. Thanks.

[Eranga]

Yeah, that's why ask the explanation from iluxa. The way you define the array is correct. There are many ways to initialize an arrays in Java. This is one of them.

[gcalvin]

Is this specifically an exercise about loading data into arrays? Because if it is not, I would recommend a more object-oriented approach. Let me know if you want more explanation.

-Gary-

[mlad]

I thought as much, thanks for clearing that up. If the OP could post exactly what problem is occuring (what happens when you run it?) it would be easier to help out.

[Eranga]

He may be still workaround on that. :p