return array from method to get objects from a hashmap - java

Question

I have a hashmap containing objects created via a constructor. These objects are in the hashmap

I have a function that compares two arrays. The one array has been manually created, but the second array is created via a method. I need only the values from the hashmap.

String[] checkOne= { "1.2:3,4:Brown", "1.1:5,4:Green" };

Map<String,RoundBrick> hashMap = new HashMap<String, RoundBrick>();

public void addBrick(RoundBrick roundBrick){
    hashMap.put(roundBrick.getRef, roundBrick)
}

checkBrick(getBricks(), one){
...
}

public static boolean checkBrick(Brick[] brick, String[] checkOne){
...
}

Where I am stuck is with this method...

public Brick[] getBricks(){

How do I convert the objects from the hashmap to an array, so I can compare the contents of the two arrays? I can go...

public Brick[] getBricks() {   
Brick[] bricks = {hashmap.value().toArray()};   
return bricks;    
}

But this give error saying cannot convert from Object[] to Brick

if I take .toArray() out, I get a "cannot convert from Collection< RoundBrick > to Brick"
if I change .toArray() to .toString(), I get a "cannot convert from String to Brick"

If I change the method to the following...

public Brick[] getBricks() {
    String a = Arrays.toString(hashmap.values().toArray());
    return a;
}

The error I get on "a" is "cannot convert from String to Brick[]"

And when adding the line below, it prints out the array.

System.out.print(hashmap.values());

[1.2:3,4:Brown, 1.1:5,4:Green]

can anyone point me into the right direction?

Why you are doing Arrays.toString(? toArray retruns Object[] array, loop it and cast to Brick and add it to Brick[]\ — kosa
– kosa, Commented Jun 29, 2012 at 19:08

Benoit · Accepted Answer · 2012-06-30 06:33:21Z

3

public Brick[] getBricks() {   
    return hashmap.values().toArray(new Brick[0]);   
}

edited Jun 30, 2012 at 6:33

answered Jun 29, 2012 at 19:10

Benoit

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3 Comments

user1031551 Over a year ago

Thank you! I tried so many variations and the answer was so simple!

Makoto Over a year ago

It would also be just as direct (perhaps save a bit on garbage collection) to implicitly return hashmap.values().toArray(new Brick[0]), but this is good anyway.

Benoit Over a year ago

I removed the useless variable

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