How do I use this method?
I'm using it like this to compare two objects:
if (key.compareTo(dictionary[numberOfEntries - i].getKey()) <= 0)
I think I'm doing something very wrong, because I am using this method to sort my generic objects, but it's not sorting correctly! I'm a bit frustrated, because I have no idea why this is failing on me.
for those of you who care, this is the code:
private int locateAddPlace(K key) {
int copyNE = numberOfEntries;
if (numberOfEntries > 0)
{
for (int i = 1; i <= numberOfEntries; i++)
{
if (key.compareTo(dictionary[numberOfEntries - i].getKey()) > 0)
return copyNE;
else if (key.compareTo(dictionary[numberOfEntries - i].getKey()) <= 0)
{
--copyNE;
}
}
}
return copyNE;
}
basically what I am doing is, I am trying to add something to a "dictionary". The dictionary works, but now I have to sort the entries I add into it. I am trying to use this method to find out exactly WHERE in my array, the newly added entry should be sorted. Yes, I am sorting as I am adding. This is my add method:
public V add(K key, V value) {
V oldValue = null;
int index;
index = locateIndex(key);
// we are adding a new [key:value] pair
if (index == -1) {
ensureCapacity();
Entry<K, V> newEntry = new Entry<K, V>(key,value);
int place = locateAddPlace(key); // finds out where the key should be.
int placeHolder = place;
if (place != (numberOfEntries))
{
for (int i = numberOfEntries; i > placeHolder; i--)
{
dictionary[i] = dictionary[i - 1];
}
dictionary[place] = newEntry;
}
else
dictionary[place] = newEntry;
numberOfEntries++;
NodeV newValue = new NodeV(value);
newValue.next = firstVNode;
firstVNode = newValue;
NodeK newKey = new NodeK(key);
newKey.next = firstKNode;
firstKNode = newKey;
}
else { // we are replacing an existing value
oldValue = getValue(key);
dictionary[index].setValue(value);
}
return oldValue;
} // end of add method.
Like I said, I have no idea why this isn't sorting. It makes sense to me.
Update:oh sorry.
numberOfEntries, is the number of entries. starts at 0 by default, goes up by 1, each time a new entry is added.
dictionary is the name of the array. dictionary has it's own sub-class, which allows me to recall the "key", which is all I really need. dictionary holds a key and a value in each array unit. key is used to find the location of the dictionary, and the value is the information that needs to be recalled. :)
Answers & Comments
Verified answer
Sort out your variables, first.
you would possibly want to implement similar and override compareTo( anotherObject). you're meant to also write the .equals() and the .hashtable() also. The Wrapper practise of short, Byte, Boolean, Integer, Double, lengthy and so on (which includes String) do have the interface already written. however, merchandise does no longer. Your Node is a custom merchandise. you may properly have the capacity to hack it out by potential of chaning your Node fee getItem() to a Wrapper, eg Integer; otherwise, search for the ORielly e book on Java6 and their rationalization about writing compareTo();