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//: containers/Maps.java

// Things you can do with Maps.

import java.util.concurrent.*;

import java.util.*;

import net.mindview.util.*;

import static net.mindview.util.Print.*;

public class Maps {

public static void printKeys(Map<Integer,String> map) {

printnb("Size = " + map.size() + ", ");

printnb("Keys: ");

print(map.keySet()); // Produce a Set of the keys

}

public static void test(Map<Integer,String> map) {

print(map.getClass().getSimpleName());

map.putAll(new CountingMapData(25));

// Map has 'Set' behavior for keys:

map.putAll(new CountingMapData(25));

printKeys(map);

// Producing a Collection of the values:

printnb("Values: ");

print(map.values());

print(map);

print("map.containsKey(11): " + map.containsKey(11));

print("map.get(11): " + map.get(11));

print("map.containsValue(\"F0\"): "

+ map.containsValue("F0"));

Integer key = map.keySet().iterator().next();

print("First key in map: " + key);

map.remove(key);

printKeys(map);

map.clear();

print("map.isEmpty(): " + map.isEmpty());

map.putAll(new CountingMapData(25));

// Operations on the Set change the Map:

map.keySet().removeAll(map.keySet());

print("map.isEmpty(): " + map.isEmpty());

}

public static void main(String[] args) {

test(new HashMap<Integer,String>());

test(new TreeMap<Integer,String>());

test(new LinkedHashMap<Integer,String>());

test(new IdentityHashMap<Integer,String>());

test(new ConcurrentHashMap<Integer,String>());

test(new WeakHashMap<Integer,String>());

}

} /* Output:

HashMap

Size = 25, Keys: [15, 8, 23, 16, 7, 22, 9, 21, 6, 1, 14, 24, 4, 19, 11, 18, 3, 12, 17, 2, 13, 20, 10, 5, 0]

Values: [P0, I0, X0, Q0, H0, W0, J0, V0, G0, B0, O0, Y0, E0, T0, L0, S0, D0, M0, R0, C0, N0, U0, K0, F0, A0]

{15=P0, 8=I0, 23=X0, 16=Q0, 7=H0, 22=W0, 9=J0, 21=V0, 6=G0, 1=B0, 14=O0, 24=Y0, 4=E0, 19=T0, 11=L0, 18=S0, 3=D0, 12=M0, 17=R0, 2=C0, 13=N0, 20=U0, 10=K0, 5=F0, 0=A0}

map.containsKey(11): true

map.get(11): L0

map.containsValue("F0"): true

First key in map: 15

Size = 24, Keys: [8, 23, 16, 7, 22, 9, 21, 6, 1, 14, 24, 4, 19, 11, 18, 3, 12, 17, 2, 13, 20, 10, 5, 0]

map.isEmpty(): true

map.isEmpty(): true

...

*///:~