Bubble sort wont work

Question

Hi, I wrote the following code that is supposed
to sort names alphabetically. It does change
the order of the names, but it really just
jumbles them up, they do not come out alpha
sorted. Can anyone see why? (the names
are stored in objects that are in turn stored
in a Vector)
Object testarray[] = new Object[vector.size()];
   vector.copyInto(testarray);
   for(int j=0; j<testarray.length;j++){
      TestObject myobject = (TestObject)custarray[j];
     // the following method toLastnameString(); is a method defined in TestObject class
      String name = myobject.toLastnameString();
      String lowname = name.toLowerCase();
     for(int i = j+1; i<testarray.length;i++){
        TestObject myobject2 = (TestObject)testarray;
String name2 = myobject2.toLastnameString();
String lowname2 = name2.toLowerCase();
if(lowname2.compareTo(lowname) < 0){
Object temp = testarray[j];
testarray[j] = testarray[i];
testarray[i] = temp;
} // end of if
} // end of inner for loop
} // end of outer for loop

Answer 1

Hi,
Is there a reason for why you want to use Bubbel Sort?
It would be better if you try this.
Collections.sort(vector, new Comparator() {
        public boolean equals(Object o) {
            return this == o;
        public int compare(Object o1, Object o2) {
            TestObject t1 = (TestObject)o1;
            TestObject t2 = (TestObject)o2;
            return t1.toLastNameString().toLowerCase()
               .compareTo(t2.toLastNameString()
               .toLowerCase());
    });This approach would be a lot safer and would out-perform bubble sort.
Remember to import java.util.Collections and java.util.Comparator.
/Roger
Hi, I wrote the following code that is supposed
to sort names alphabetically. It does change
the order of the names, but it really just
jumbles them up, they do not come out alpha
sorted. Can anyone see why? (the names
are stored in objects that are in turn stored
in a Vector)
Object testarray[] = new Object[vector.size()];
vector.copyInto(testarray);
for(int j=0; j<testarray.length;j++){
TestObject myobject = (TestObject)custarray[j];
// the following method toLastnameString(); is a
is a method defined in TestObject class
String name = myobject.toLastnameString();
String lowname = name.toLowerCase();
for(int i = j+1; i<testarray.length;i++){
TestObject myobject2 =
ject2 = (TestObject)testarray;
String name2 = myobject2.toLastnameString();
String lowname2 = name2.toLowerCase();
if(lowname2.compareTo(lowname) < 0){
Object temp = testarray[j];
testarray[j] = testarray[i];
testarray[i] = temp;
} // end of if
} // end of inner for loop
} // end of outer for loop