I'm new in java, what is the right way to add/pass a value into array string without specifying the array index.
I want to add a value into array like what in php array do.
static String[] var_productname = new String[20];
public void setProductName(String productName){
var_productname[] = productName;
}
You can use an List implementation as ArrayList.
Based on your example:
static List<String> var_productname = new ArrayList<>();
public void setProductName(String productName){
var_productname.add(productName);
}
The initial capacity is optional, but you can instantiate the array using new ArrayList<>(20), where 20 is the initial (not maximum) capacity.
If you are just trying to avoid specifying the index when calling setProductName, here is a simple approach. (However, the method will internally use and update the index).
Note that this simple implementation will throw an exception if you attempt to append more than 20 strings. Also, I made setProductName a static method, which makes more sense since you made var_productname static.
static String[] var_productname = new String[20];
static int pnIndex = 0;
public static void setProductName(String productName) {
var_productname[pnIndex++] = productName;
}
array can't append element direct,change array to other data structure
In that case you would go for a concept called Collections
The problem with Arrays is that you cannot dynamically increase it's size at run time and you will only be able to add values as per the length specified.
As int[] nArray= new int[20]; will hold only 20 items you cannot further dynamically increase the size from 20 to 21 and add the element.
As suggested above you can go for any List implementation.
staticdoesn't play well with setter methods 3) Why is a "productName" an array? Sounds like a singular object