By providing proper implentation for the key class as shown below with the equals() and hashCode() methods.
…..
static class Key {
private String key;
public Key(String key) {
this.key = key;
}
@Override
public boolean equals(Object obj) {
if (obj instanceof Key)
return key.equals(((Key) obj).key);
else
return false;
}
@Override
public int hashCode() {
return key.hashCode();
}
}
…..
If you rerun it after making the fix shown above to the MemoryLeak class, you will get an output as shown below. The program runs endlessly, and creates only one object in the HashMap.
map size: 1
Free memory after count 1000 is 4MB
map size: 1
Free memory after count 2000 is 4MB
map size: 1
Free memory after count 3000 is 4MB
map size: 1
Free memory after count 4000 is 4MB
…
Free memory after count 73000 is 4MB
map size: 1
Free memory after count 74000 is 4MB
map size: 1
Free memory after count 75000 is 4MB