Split into separate arrarys

Question

All the split command I have seen split (for example) a CSV file into the 1 array.

e.g.

cat,feline,house
dog,canine,house
monkey,primate,zoo

Into

array[0] = cat    
array[1] = feline
array[2] = house

Is there a way to split them into separate arrays per line so it would be more like (so you can keep specific attributes in the same lines of the csv: into

animal[0] = cat    
species[0] = feline
lives[0] = house

there is no common way to do this, you will need to write your own method for this. — Dennis Kriechel, Aug 18 '13 at 12:11

score 3 · Answer 1 · edited Aug 18 '13 at 12:15

3

A much better approach is to create a POJO:

public class MyAnimal {
    private String animal;
    private String family;
    private String place;
    private String country;
    // getters and setters...
}

Then you can use a parser or read the file line by line and convert it to a List<MyAnimal>

Using array to hold object data is not the way to do it.

edited Aug 18 '13 at 12:15

keyser

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answered Aug 18 '13 at 12:11

BobTheBuilder

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1

How about `MyAnimal`? :) – keyser Aug 18 '13 at 12:13
Even better idea would be to follow naming conventions: name the class `Animal`. Name the band field `name` – Bohemian Aug 18 '13 at 12:14

vallentin · Answer 2 · 2013-08-18T13:29:15.710

Such an abstract split does not exist as a default as far as I know.

The basic way you would go about achieving this, would be first to do the regular split as you said, which gave the result.

array[0] = cat    
array[1] = feline
array[2] = house

Then you could loop through the array and check for the different things.

ArrayList<String> animals = new ArrayList<String>();
ArrayList<String> lives = new ArrayList<String>();

for (int i = 0; i < array.length; i++) {
    if (array[i].equalsIgnoreCase("cat") || array[i].equalsIgnoreCase("dog")) {
        animals.add(array[i]);
    }
    else if (array[i].equalsIgnoreCase("house") || array[i].equalsIgnoreCase("zoo")) {
        lives.add(array[i]);
    }
}

Then you would of course do that for all the cases you have. It's a pretty complex way to do it, though really simple to understand.

Edit

To achive what you asked in the comments, you could do something like this.

ArrayList<String> animals = new ArrayList<String>();
ArrayList<String> lives = new ArrayList<String>();

for (int i = 0; i < array.length; i += 5) {
    animals.add(array[i]);
    lives.add(array[i + 1]);
}

Then the + 1 for selecting the index in the array would of course depend on the index from the splitted String.

true that does sound like a nice way to go. is it possible to put it so every 5th instance of the array array[5] , array [10], array[15] becomes animal[0], animal[1], animal[3]? — Dylan Benton, Aug 18 '13 at 13:00

score 1 · Accepted Answer · answered Aug 18 '13 at 12:16

You can try this

BufferedReader br = new BufferedReader(new FileReader("D:\\sample.txt"));
    String st = null;
    String[] animal = new String[10];
    String[] species = new String[10];
    String[] lives = new String[10];
    int j = 0;
    while ((st = br.readLine()) != null) {
        String[] str = st.split(",");

        for (int i = 0; i < str.length; i++) {
            animal[j] = str[0];
            species[j] = str[1];
            lives[j] = str[2];
        }
        j++;
    }

But it is better to use ArrayList here.

Roman C · Answer 4 · 2013-08-18T12:37:00.523

String.split works like separating items by the delimiters, it doesn't know what a item is. If you want to associate items on some pattern to be recognized when parsing the string, you should supply those patterns to the categories the items should be associated to. If it's a CSV and you want to get the table data, then you should supply the metadata described the column names and dimensions. Without this metadata it's impossible to parse your document correctly.

Split into separate arrarys

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