I know how to read a file with Java using Scanner and File IOException, but the only thing I don't know is how to store the text in the files as an array.
Here is a snippet of my code:
public static void main(String[] args) throws IOException{ // TODO code application logic here // // read KeyWestTemp.txt // create token1 String token1 = ""; // for-each loop for calculating heat index of May - October // create Scanner inFile1 Scanner inFile1 = new Scanner(new File("KeyWestTemp.txt")); // while loop while(inFile1.hasNext()){ // how can I create array from text read? // find next line token1 = inFile1.nextLine(); Here is what my KeyWestTemp.txt file contains:
70.3, 70.8, 73.8, 77.0, 80.7, 83.4, 84.5, 84.4, 83.4, 80.2, 76.3, 72.0 7 Answers
Stored as strings:
public class ReadTemps { public static void main(String[] args) throws IOException { // TODO code application logic here // // read KeyWestTemp.txt // create token1 String token1 = ""; // for-each loop for calculating heat index of May - October // create Scanner inFile1 Scanner inFile1 = new Scanner(new File("KeyWestTemp.txt")).useDelimiter(",\\s*"); // Original answer used LinkedList, but probably preferable to use ArrayList in most cases // List<String> temps = new LinkedList<String>(); List<String> temps = new ArrayList<String>(); // while loop while (inFile1.hasNext()) { // find next line token1 = inFile1.next(); temps.add(token1); } inFile1.close(); String[] tempsArray = temps.toArray(new String[0]); for (String s : tempsArray) { System.out.println(s); } } } For floats:
import java.io.File; import java.io.IOException; import java.util.LinkedList; import java.util.List; import java.util.Scanner; public class ReadTemps { public static void main(String[] args) throws IOException { // TODO code application logic here // // read KeyWestTemp.txt // create token1 // for-each loop for calculating heat index of May - October // create Scanner inFile1 Scanner inFile1 = new Scanner(new File("KeyWestTemp.txt")).useDelimiter(",\\s*"); // Original answer used LinkedList, but probably preferable to use ArrayList in most cases // List<Float> temps = new LinkedList<Float>(); List<Float> temps = new ArrayList<Float>(); // while loop while (inFile1.hasNext()) { // find next line float token1 = inFile1.nextFloat(); temps.add(token1); } inFile1.close(); Float[] tempsArray = temps.toArray(new Float[0]); for (Float s : tempsArray) { System.out.println(s); } } } If you don't know the number of lines in your file, you don't have a size with which to init an array. In this case, it makes more sense to use a List :
List<String> tokens = new ArrayList<String>(); while (inFile1.hasNext()) { tokens.add(inFile1.nextLine()); } After that, if you need to, you can copy to an array :
String[] tokenArray = tokens.toArray(new String[0]); Just read the whole file into a StringBuilder, then split the String by dot following a space. You will get a String array.
Scanner inFile1 = new Scanner(new File("KeyWestTemp.txt")); StringBuilder sb = new StringBuilder(); while(inFile1.hasNext()) { sb.append(inFile1.nextLine()); } String[] yourArray = sb.toString().split(", "); while(inFile1.hasNext()){ token1 = inFile1.nextLine(); // put each value into an array with String#split(); String[] numStrings = line.split(", "); // parse number string into doubles double[] nums = new double[numString.length]; for (int i = 0; i < nums.length; i++){ nums[i] = Double.parseDouble(numStrings[i]); } } int count = -1; String[] content = new String[200]; while(inFile1.hasNext()){ content[++count] = inFile1.nextLine(); } EDIT
Looks like you want to create a float array, for that create a float array
int count = -1; Float[] content = new Float[200]; while(inFile1.hasNext()){ content[++count] = Float.parseFloat(inFile1.nextLine()); } then your float array would look like
content[0] = 70.3 content[1] = 70.8 content[2] = 73.8 content[3] = 77.0 and so on I have found this way of reading strings from files to work best for me
String st, full; full=""; BufferedReader br = new BufferedReader(new FileReader(URL)); while ((st=br.readLine())!=null) { full+=st; } "full" will be the completed combination of all of the lines. If you want to add a line break between the lines of text you would do full+=st+"\n";
I use this method:
import java.util.Scanner; import java.io.File; import java.io.FileNotFoundException; public class TEST { static Scanner scn; public static void main(String[] args) { String text = ""; try{ scn = new Scanner(new File("test.txt")); }catch(FileNotFoundException ex){System.out.println(ex.getMessage());} while(scn.hasNext()){ text += scn.next(); } String[] arry = text.split(","); //if need converting to float do this: Float[] arrdy = new Float[arry.length]; for(int i = 0; i < arry.length; i++){ arrdy[i] = Float.parseFloat(arry[i]); } System.out.println(Arrays.toString(arrdy)); } } 
