Java多维数组未正确填充

Question

I have declared a multi- dimensional array like this:

String[][] contentDetails  = {};    

I populated the array like this:

contentDetails[][]  = {{"Availability","Available from: "+empst}, 
                     {"Rate in EUR/Hour",rst.getString(25)}};

It is getting error. How can I do that? I am new this. Please help me.

What I want is an empty array first and then need to populate!!

Answer 1

This is because array constants can only be used in initializers.

The following would work:

 String[][] contentDetails  = {{"Availability","Available from: "+empst}, 
                                {"Rate in EUR/Hour", rst.getString(25)}};

If you don't want to fill it on instantiation you need to instantiate the array giving it the length for both dimensions like this:

String[][] contentDetails = new String [length1][length2];

where length1 and length2 are integers (int).

Answer 2

You can only use Arrays constant when creating the array, not after. It make sense because, how Java would know the size of the array when instantiating otherwise ?

So you can do this

String[][] contentDetails = {{"Availability","Available from: "+empst}, 
            {"Rate in EUR/Hour",rst.getString(25)}};

or declare the array then loop over it to set the values

String[][] contentDetails [2][2];

...

for(int i = 0;i<2;i++)
  for(int j = 0;j<2;j++)
    //set the value of contentDetails here

Answer 3

The correct syntax in Java looks like this:

String[][] contentDetails = new String[][] {
    new String[] { "Availability", "Available from: "+empst }, 
    new String[] { "Rate in EUR/Hour", rst.getString(25) }
};