package org.eclipse.update.internal.ui; | |
/* | |
* (c) Copyright IBM Corp. 2000, 2001. | |
* All Rights Reserved. | |
*/ | |
/** | |
* | |
*/ | |
import java.util.Comparator; | |
public class UMWizardTreeItemComparator implements Comparator { | |
/** | |
* UpdateManagerTreeItemComparator constructor comment. | |
*/ | |
public UMWizardTreeItemComparator() { | |
super(); | |
} | |
/** | |
* Compares its two arguments for order. Returns a negative integer, | |
* zero, or a positive integer as the first argument is less than, equal | |
* to, or greater than the second.<p> | |
* | |
* The implementor must ensure that <tt>sgn(compare(x, y)) == | |
* -sgn(compare(y, x))</tt> for all <tt>x</tt> and <tt>y</tt>. (This | |
* implies that <tt>compare(x, y)</tt> must throw an exception if and only | |
* if <tt>compare(y, x)</tt> throws an exception.)<p> | |
* | |
* The implementor must also ensure that the relation is transitive: | |
* <tt>((compare(x, y)>0) && (compare(y, z)>0))</tt> implies | |
* <tt>compare(x, z)>0</tt>.<p> | |
* | |
* Finally, the implementer must ensure that <tt>compare(x, y)==0</tt> | |
* implies that <tt>sgn(compare(x, z))==sgn(compare(y, z))</tt> for all | |
* <tt>z</tt>.<p> | |
* | |
* It is generally the case, but <i>not</i> strictly required that | |
* <tt>(compare(x, y)==0) == (x.equals(y))</tt>. Generally speaking, | |
* any comparator that violates this condition should clearly indicate | |
* this fact. The recommended language is "Note: this comparator | |
* imposes orderings that are inconsistent with equals." | |
* | |
* @return a negative integer, zero, or a positive integer as the | |
* first argument is less than, equal to, or greater than the | |
* second. | |
* @throws ClassCastException if the arguments' types prevent them from | |
* being compared by this Comparator. | |
*/ | |
public int compare(java.lang.Object o1, java.lang.Object o2) { | |
if (o1 instanceof UMWizardTreeItem && o2 instanceof UMWizardTreeItem) { | |
if (((UMWizardTreeItem) o1)._strName != null && ((UMWizardTreeItem) o2)._strName != null) { | |
return ((UMWizardTreeItem) o1)._strName.compareTo(((UMWizardTreeItem) o2)._strName); | |
} | |
} | |
return 0; | |
} | |
} |