Date: 2012mar30
Language: Java
Keywords: enumerate, loop, iterate
Q. Java: How can I get all the values in a HashMap ?
A. If you have:
HashMap<String, Integer> mymap = new HashMap<String, Integer>();
If you only want the keys...
for (String key : mymap.keySet()) {
// ...
}
If you only want the values
for (Integer value : mymap.values()) {
// ...
}
If you want both the keys and values...
import java.util.HashMap;
import java.util.Map;
for (Map.Entry<String, Integer> entry : mymap.entrySet()) {
String key = entry.getKey();
Integer value = entry.getValue();
// ...
}
Or you can use an iterator...
Iterator<Map.Entry<String, Integer>> it = mymap.entrySet().iterator();
while (it.hasNext()) {
Map.Entry<String, Integer> entry = it.next();
String key = entry.getKey();
Integer value = entry.getValue();
// ...
}
I have read using an iterator is faster but it doesn't look as nice.