How to align String on console output

Question

I've to write code for:

I'd written the code:

public class tables {
    public static void main(String[] args) {
        //int[][] table = new int[12][12];
        String table="";
        for(int i=1; i<13; i++){
            for(int j=1; j<13; j++){
                //table[i-1][j-1] = i*j;
                table+=(i*j)+" ";
            }
            System.out.println(table.trim());
            table="";
        }
    }
}

But the problem is with the output format. I need the output in a matrix like fashion, each number formatted to a width of 4 (the numbers are right-aligned and strip out leading/trailing spaces on each line). I'd tried google but not find any good solution to my problem. Can anybody help me out?

Answer 1

I made an OutputFormatter class which formats the Strings you give it:

OutputFormatter formatter = new OutputFormatter();
formatter.add("Asus", "20000");
formatter.add("INTEL", "45000");
formatter.add("Nvidia gtx 1050ti", "17000");
formatter.add("Asus", "18000");
formatter.add("Samsung", "20000");
formatter.add("Coolermaster", "20000");
formatter.add("Ortis", "4000");
formatter.add("Asus", "4000");
System.out.println(formatter.format());

The output looks like this:

Asus              20000
INTEL             45000
Nvidia gtx 1050ti 17000
Asus              18000
Samsung           20000
Coolermaster      20000
Ortis             4000 
Asus              4000 

You can give the add() method on the OutputFormatter as much Strings as you would like, it takes them all into account.

---

This is the OutputFormatter class:

import java.util.ArrayList;
import java.util.List;

public class OutputFormatter {
    private List<String[]> contents;

    public OutputFormatter() {
        contents = new ArrayList<>();
    }

    public void add(String... fields) {
        contents.add(fields);
    }

    public void clear() {
        contents.clear();
    }

    public String format() {
        StringBuilder ret = new StringBuilder();
        List<Integer> lengths = new ArrayList<>();
        int maxContentLen = 0;
        for (String[] row : contents) {
            maxContentLen = Math.max(maxContentLen, row.length);
        }

        for (int i = 0; i < maxContentLen; i++) {
            int len = 1;
            for (String[] row : contents) {
                try {
                    len = Math.max(len, row[i].length());
                } catch (IndexOutOfBoundsException ignore) {}
            }
            lengths.add(len);
        }

        for (String[] row : contents) {
            for (int i = 0; i < row.length; i++) {
                ret.append(row[i] + " ".repeat(lengths.get(i) - row[i].length() + 1));
            }
            ret.append(System.lineSeparator());
        }

        return ret.toString();
    }
}

Answer 2

Formatting of output can be done using the System.out.format("","") method this method contain two input parameter first define the formatting style and second define value to be print. Let us assume you want to the n digit value right align. you will pass the first parameter "%4d".

For the left align use -ve %-nd

For right align use +ve %nd

 for(int i=1; i<13; i++){
       for(int j=1; j<13; j++){
            System.out.format("%4d", i * j);  //each number formatted to a width of 4 so use %4d in the format method.
    }
    System.out.println();  // To move to the next line.
}

Answer 3

In my example the array contains character string's with different length and due to that I was unable to arrange string and other strings of different arrays were mis-match on console. with a different concept I could arrange those arrays on console my codes are as below.

package arrayformat;

 /**
 *
 * @author Sunil
 */
 public class ArrayFormat {



  /**
  * @param args the command line arguments
  */

  public static void main(String[] args) {

  int[] productId = new int[]  
 {1001,1002,1003,1004,1005,1006,1007,1008,1009,1010,};
   String[] productName= new String[]{"Pepsi","kissan jam","Herbal 
 oil","Garnier man's","Lays chips","biscuits","Bournvita","Cadbury","Parker 
 Vector","Nescafe",};
   String[] productType = new String[]{"Cold Drink","Jam","Oil","Face 
 wash","chips","Biscuits","Health 
 Supplement","Chocolate","Stationary","Coffee",};
    float[] productPrice = new float[]{24,65,30,79,10,20,140,20,150,80,}; 


       int productNameMaxlength=0;
   int productTypeMaxlength=0;



    for (String productName1 : productName) {
        if (productNameMaxlength < productName1.length()) {
            productNameMaxlength = productName1.length();
        }
    }


    for (String productType1 : productType) {
        if (productTypeMaxlength < productType1.length()) {
            productTypeMaxlength = productType1.length();
        }
    }



   for(int i=0;i<productType.length;i++)

   { 
              System.out.print(i);

      System.out.print("\t");

              System.out.print(productId[i]);

              System.out.print("\t");

              System.out.print(productName[i]);

       for(int j=0;j<=productNameMaxlength-productName[i].length
     ();j++)

       {

        System.out.print(" ");

       }

       System.out.print("\t");

       System.out.print(productType[i]);

       for(int j=0;j<=productTypeMaxlength-productType[i].length
    ();j++)

       {
           System.out.print(" ");
       }

               System.out.print("\t");

       System.out.println(productPrice[i]);
          }           
      }

    }
   and output is--
  Sr.No  ID     NAME            TYPE               PRICE
   0    1001    Cadbury         Chocolate           20.0
   1    1002    Parker Vector   Stationary          150.0
   2    1003    Nescafe         Coffee              80.0
   3    1004    kissan jam      Jam                 65.0
   4    1005    Herbal oil      Oil                 30.0
   5    1006    Garnier man's   Face wash           79.0
   6    1007    Lays chips      chips               10.0
   7    1008    biscuits        Biscuits            20.0
   8    1009    Bournvita       Health Supplement   140.0
   9    1010    Pepsi           Cold Drink          24.0

Since I am unable to answer my question where I have ask my question because of block to ask question and answer I am quoting my answer and this was a different kind of array format I feel.

Answer 4

You can use format() to format your output according to your need..

    for(int i=1; i<13; i++){
        for(int j=1; j<13; j++){

           System.out.format("%5d", i * j);
        }
        System.out.println();  // To move to the next line.
    }

Or, you can also use: -

System.out.print(String.format("%5d", i * j));

in place of System.out.format..

Here's is the explanation of how %5d works: -

• First, since we are printing integer, we should use %d which is format specifier for integers..
• 5 in %5d means the total width your output will take.. So, if your value is 5, it will be printed to cover 5 spaces like this: - ****5
• %5d is used to align right.. For aligning left, you can use %-5d. For a value 5, this will print your output as: - 5****