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Passing a string array as a parameter to a function java

I would like to pass a string array as a parameter to a function. Please look at the code below

String[] stringArray = {'a', 'b', 'c', 'd', 'e'};

functionFoo(stringArray);

Instead of:

functionFoo('a', 'b', 'c', 'd', 'e');

but if I do this I am getting an error stating that convert String[] into String . I would like to know if it is possible to pass the values like that or what is the correct way to do it.

How about:

public class test {
    public static void someFunction(String[] strArray) { 
        // do something 
    }

    public static void main(String[] args) {
        String[] strArray = new String[]{"Foo","Bar","Baz"};
        someFunction(strArray);
    }
}

All the answers above are correct. But just note that you'll be passing the reference to the string array when you pass like this. If you make any modifications to the array in your called function, it will be reflected in the calling function also.

There is another concept called variable arguments in Java which you can look into. It basically works like this. Eg:-

 String concat (String ... strings)
   {
      StringBuilder sb = new StringBuilder ();
      for (int i = 0; i < strings.length; i++)
           sb.append (strings [i]);
      return sb.toString ();
   }

Here we can call the function like concat(a,b,c,d) or any number of params you want.

More Info: http://today.java.net/pub/a/today/2004/04/19/varargs.html

I believe this should be the way this is done...

    public static void function(String [] array){
    ...
    }

And the calling will be done like...

    public void test(){
        String[] stringArray = {"a","b","c","d","e","f","g","h","t","k","k","k","l","k"};
        function(stringArray);
    }

look at familiar main method which takes string array as param

More than likely your method declaration is incorrect. Make sure the methods parameter is of type String array (String[]) and not simply String and that you use double quotes around your strings in the array declaration.

private String[] stringArray = {"a","b","c","d","e","f","g","h","t","k","k","k"};
public void myMethod(String[] myArray) {}

I think you forget to register the parameter as String[]

Feel free to use this how ever you like.

/*
 * The extendStrArray() method will takes a number "n" and
 * a String Array "strArray" and will return a new array
 * containing 'n' new positions. This new returned array
 * can then be assigned to a new array, or the existing
 * one to "extend" it, it contain the old value in the 
 * new array with the addition n empty positions.
 */
private String[] extendStrArray(int n, String[] strArray){
    String[] old_str_array = strArray;
    String[] new_str_array = new String[(old_str_array.length + n)];
    for(int i = 0; i < old_str_array.length; i++ ){
        new_str_array[i] = old_str_array[i];
    }//end for loop

    return new_str_array;

}//end extendStrArray()

Basically I would use it like this:

String[] students = {"Tom", "Jeff", "Ashley", "Mary"};
// 4 new students enter the class so we need to extend the string array
students = extendStrArray(4, students); //this will effectively add 4 new empty positions to the "students" array.

please check the below code for more details


package FirstTestNgPackage;

import java.util.ArrayList;
import java.util.Arrays;


public class testingclass {

    public static void main(String[] args) throws InterruptedException {
        // TODO Auto-generated method stub
        System.out.println("Hello");
        
        int size = 7;
        String myArray[] = new String[size];
        System.out.println("Enter elements of the array (Strings) :: ");
        for(int i=0; i<size; i++)
        {
        myArray[i] = "testing"+i;
        }
        System.out.println(Arrays.toString(myArray));
        
        
        ArrayList<String> myList = new ArrayList<String>(Arrays.asList(myArray));
        
        
        System.out.println("Enter the element that is to be added:");
        
        myArray = myList.toArray(myArray);
        
        someFunction(myArray);
        }
    
    public static void someFunction(String[] strArray) 
    { 
        System.out.println("in function");
        System.out.println("in function length"+strArray.length );
        System.out.println(Arrays.toString(strArray));
        
           }
        }

just copy it and past... your code.. it will work.. and then you understand how to pass string array as a parameter...

Thank you

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