转换ArrayList <ArrayList<Object> &gt;转到对象[] []

Question

I would like to populate a JTable with the cnstructor like this :

new JTable(datas, columns);

so I need an Object[] for the columns and a Object[][] for the datas. The problem is when I try to get the datas.

In one of my method I work with an ArrayList<ArrayList<Object>> and I would like to cast it to an Object[][] .

Here's a sample of my code :

ArrayList<ArrayList<Object>> datas = new ArrayList<ArrayList<Object>>();

for (Map.Entry<Integer, JSObject> entry : params.entrySet()) {
    datas.add(entry.getValue().getValues()); // getValues returns an ArrayList<Object>
}

return new datas.toArray(); //  not seems to work

I saw in this question Convert ArrayList<Object[]> to Object[][] some idea, but I'm not sure about the result.

Thanks in advance !

Answer 1

Can't you just change the type of datas to an ArrayList<Object[]> , and use toArray() each time you add an element:

ArrayList<Object[]> datas = new ArrayList<Object[]>();
for (Map.Entry<Integer, JSObject> entry : params.entrySet()) {
    datas.add(entry.getValue().getValues().toArray());
}
return datas.toArray(new Object[][]{});