qu0ll,

There are lots of ways to do this depending on your actual goal.

As a HashMap has keys and values, is your end goal to have an array of
{something} in the order that the keys are sorted or based on how the
{something}'s should be ordered on their own?

If its the later, you probably want to create a Comparator for each
{something} you want to sort.

Here is a simple example - not sure if its exactly what you want but
hopefully it helps.

/* Begin qu0ll.java */
import java.util.*;

public class qu0ll {
 public static void main(String args[]) {
   qu0llSomethingComparator c = new qu0llSomethingComparator();
   qu0llSomething[] myArray = new qu0llSomething[args.length];

   for (int i = 0; i < args.length; i ++) {
     myArray[i] = new qu0llSomething(args[i]);
   }

   Arrays.sort(myArray, c);

   for (qu0llSomething q : myArray) {
     System.out.println(q);
   }
 }
}
/* Begin qu0llSomethingComparator.java */
import java.util.*;

public class qu0llSomethingComparator implements
Comparator<qu0llSomething> {
 public int compare(qu0llSomething q1, qu0llSomething q2) {
   // Specialized rules for ordering go here

   if (q1.getLength() < q2.getLength()) {
     return -1;
   }
   else if (q1.getLength() == q2.getLength()) {
     if (q1.hashCode()  < q2.hashCode()) {
       return -1;
     }
     else if (q1.hashCode() > q2.hashCode()) {
       return 1;
     }
     else {
       return 0;
     }
   }
   else {
     return 1;
   }
 }

 public boolean equals(Object o) {
   return (o == this);
 }
}
/* Begin qu0llSomething.java */
public class qu0llSomething {
 private String value;

 public qu0llSomething(String value) {
   this.value = value;
 }

 // Will throw NullPointerException if value is null
 public int getLength() {
   return value.length();
 }

 public String getValue() {
   return value;
 }

 public String toString() {
   return getValue();
 }
}

--

Let me know if I can assist further.

-kavaj

There's a more concise way:

    public Thing[] convert(HashMap<String, Thing> things)
    {
       Thing[] tArray = things.values().toArray(new Thing[things.size()]);
       Arrays.sort(tArray);
       return tArray;
    }

You could use generics to write a version that will work with any Map (not  
just HashMap).  The signature would look like this:

    public <T extends Comparable> T[] convert(Map<?, T> things)

However, generics and arrays don't mix very well so the implementation  
might be a little bit ugly.  It's just about impossible to derive the  
correct type of T at runtime in this instance, so this might have to  
weakened to this:

    public Object[] convert(Map<?, ? extends Comparable> things)

Consider using Lists instead of arrays.

Dan.

qu0ll,

There are lots of ways to do this depending on your actual goal.

As a HashMap has keys and values, is your end goal to have an array of
{something} in the order that the keys are sorted or based on how the
{something}'s should be ordered on their own?

If its the later, you probably want to create a Comparator for each
{something} you want to sort.

Here is a simple example - not sure if its exactly what you want but
hopefully it helps.

/* Begin qu0ll.java */
import java.util.*;

public class qu0ll {
 public static void main(String args[]) {
   qu0llSomethingComparator c = new qu0llSomethingComparator();
   qu0llSomething[] myArray = new qu0llSomething[args.length];

   for (int i = 0; i < args.length; i ++) {
     myArray[i] = new qu0llSomething(args[i]);
   }

   Arrays.sort(myArray, c);

   for (qu0llSomething q : myArray) {
     System.out.println(q);
   }
 }
}
/* Begin qu0llSomethingComparator.java */
import java.util.*;

public class qu0llSomethingComparator implements
Comparator<qu0llSomething> {
 public int compare(qu0llSomething q1, qu0llSomething q2) {
   // Specialized rules for ordering go here

   if (q1.getLength() < q2.getLength()) {
     return -1;
   }
   else if (q1.getLength() == q2.getLength()) {
     if (q1.hashCode()  < q2.hashCode()) {
       return -1;
     }
     else if (q1.hashCode() > q2.hashCode()) {
       return 1;
     }
     else {
       return 0;
     }
   }
   else {
     return 1;
   }
 }

 public boolean equals(Object o) {
   return (o == this);
 }
}
/* Begin qu0llSomething.java */
public class qu0llSomething {
 private String value;

 public qu0llSomething(String value) {
   this.value = value;
 }

 // Will throw NullPointerException if value is null
 public int getLength() {
   return value.length();
 }

 public String getValue() {
   return value;
 }

 public String toString() {
   return getValue();
 }
}

--

Let me know if I can assist further.

-kavaj

There has a complete example at following link

http://www.developerzone.biz/index.php?option=com_content&task=view&id=90&Itemid=36

Hope it helps