Transform array to list

Question

I have the following fragment of code:

public void doSomething() {
  float array[] = new float[2];
  array[0] = (float) 0.0;
  array[1] = (float) 1.2;
  someMethod(array);
}

public void someMethod(Object value) {
   //need to convert value to List<Float>
}

As you can see above I want to convert the value variable which is an array (but passed as an Object) to List. I tried the following as suggested here: Create ArrayList from array

    new ArrayList<Float> (Arrays.asList(value));

however, it does not compile.

Any hints?

Answer 1

public void someMethod(Object value) {
    float[] array = (float[]) value;
    List<Float> result = new ArrayList<Float>(array.length);
    for (float f : array) {
        result.add(Float.valueOf(f));
    }
    // ...
}

I don't know why you're not defining the value argument as a float[] rather than an Object, though.

Answer 2

[Updated per JB Nizet's correction.] If you use Float instead of float for the array, it will work if the compiler knows that value is an array - which it doesn't. Add a cast:

new ArrayList<Float> (Arrays.asList((Float[])value));

or just change the parameter type of value to Float[], and leave out the cast.

Answer 3

If you want to view a float[] as a List<Float> then Guava's Floats.asList method will get the job done.