Working with HashMaps
HashMaps are similar to arrays, but they use a different method for accessing elements. Arrays use an integer for the index, while HashMaps use a String. HashMaps are really useful when you need to search for a specific item in a large collection of data.
How to do it...
We start by declaring a HashMap object and adding some values to it, inside the setup() function.
HashMap<String, Float> hm;
void setup()
{
hm = new HashMap<String, Float>();
hm.put("Processing", 51.30);
hm.put("openFrameworks", 30.45);
hm.put("Cinder", 12.78);
noLoop();
}The first thing we'll do inside the draw() function is loop through the HashMap object using an Iterator and print each entry to the console.
Iterator i = hm.entrySet().iterator();
while ( i.hasNext () ) {
Map.Entry me = (Map.Entry)i.next();
println( "Key: " + me.getKey() + ", Value: " + me.getValue() );
}
println("---");If you want to check whether a HashMap is empty, you can do that with the isEmpty() method...