String Array in java

Applications Programming
1

Hi ,

I wonder how I can set up an String array in java. I need the array so I can store different items per line so each item will be like one record. I tried something like :

String x[] = new String[10];

but when it comes to storing the data and retrieve the is when I struggle. The problem is I know that I can use x.length or other methods available to traverse the array but I believe I could be doing something wrong. Thanks.

2

Well, once you've declared the String array, you could assign values to array elements individually. Or you could use a loop to do that.
And after all array elements have been assigned their values, you could use a for loop to print them.

In the following Java program, I use both methods - individual assignment as well as assignment inside a loop.

Assignment inside a loop would typically be based on your business logic. Since my program is just a demo, I generated a random string of 20 characters inside a loop and assigned that to each String array element.

$
$
$ cat -n TestStringArray.java
     1  import java.util.Random;
     2  class TestStringArray {
     3    public static void main (String[] args) {
     4      String[] x = new String[9];
     5      // Now assign values to each array element
     6      x[0] = "The ";
     7      x[1] = "quick ";
     8      x[2] = "brown ";
     9      x[3] = "fox ";
    10      x[4] = "jumps ";
    11      x[5] = "over ";
    12      x[6] = "the ";
    13      x[7] = "lazy ";
    14      x[8] = "dog.";
    15      // and print them
    16      for (int i=0; i<x.length; i++){
    17        System.out.println("Element # "+i+" in string array x => "+x);
    18      }
    19      System.out.println();
    20      // =========================================================================
    21      // You could also assign values inside a loop
    22      Random rnd = new Random();
    23      char[] ch = new char[20];
    24      for (int i=0; i<9; i++) {
    25        // Create a string of 20 random characters
    26        for (int j=0; j<20; j++) {
    27          ch[j] = (char)(rnd.nextInt(94)+33);
    28        }
    29        // convert the character array element to a String and assign it
    30        x = new String(ch);
    31      }
    32      // Now loop through String array and print each element
    33      System.out.println("==========================================================\n");
    34      for (int i=0; i<x.length; i++){
    35        System.out.println("Element # "+i+" in string array x => "+x);
    36      }
    37    }
    38  }
$
$ javac TestStringArray.java
$
$ java TestStringArray
Element # 0 in string array x => The
Element # 1 in string array x => quick
Element # 2 in string array x => brown
Element # 3 in string array x => fox
Element # 4 in string array x => jumps
Element # 5 in string array x => over
Element # 6 in string array x => the
Element # 7 in string array x => lazy
Element # 8 in string array x => dog.
 
==========================================================
 
Element # 0 in string array x => dl2q>|C3HMj>7$MH]6=e
Element # 1 in string array x => &zw.P[NO/VH/0:[*Ti&i
Element # 2 in string array x => wu%2<S``Kx6r+4Qx%@g@
Element # 3 in string array x => \?:TG3bqDEza>oA{XjS2
Element # 4 in string array x => jl,s(#'9A!1g2fvCh*D3
Element # 5 in string array x => iZx=(c*{ihef4tX`/[z&
Element # 6 in string array x => p"\$DImMBRK9'4Of*8X3
Element # 7 in string array x => n'"]JCt@^lm;2N5A5dD1]n',
Element # 8 in string array x => \$n#03&):Z7B%lKaf{=%
$
$

HTH,
tyler_durden

3

Thanks Tyler really appreciate your good comments. Much appreciated.