Examples of java.util.Comparator.compare()

java.util.Comparator.compare()
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.
In the foregoing description, the notation sgn(expression) designates the mathematical signum function, which is defined to return one of -1, 0, or 1 according to whether the value of expression is negative, zero or positive.
The implementor must ensure that sgn(compare(x, y)) == -sgn(compare(y, x)) for all x and y. (This implies that compare(x, y) must throw an exception if and only if compare(y, x) throws an exception.)
The implementor must also ensure that the relation is transitive: ((compare(x, y)>0) && (compare(y, z)>0)) implies compare(x, z)>0.
Finally, the implementor must ensure that compare(x, y)==0 implies that sgn(compare(x, z))==sgn(compare(y, z)) for all z.
It is generally the case, but not strictly required that (compare(x, y)==0) == (x.equals(y)). 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." @param o1 the first object to be compared. @param o2 the second object to be compared. @return a negative integer, zero, or a positive integer as thefirst argument is less than, equal to, or greater than the second. @throws ClassCastException if the arguments' types prevent them frombeing compared by this comparator.

            SortField sortField = iterator.next();
            SortOrder sortOrder = sortField.getSortOrder();
            if (sortOrder != null && !SortOrder.unsorted.equals(sortOrder)) {
                Comparator comparator = sortField.getComparator();
                if (comparator != null) {
                    result = comparator.compare(object1, object2);
                } else {
                    ValueExpression sortBy = sortField.getSortBy();
                    if (sortBy != null) {
                        updateVar(context, var, object1);
                        Object value1 = sortBy.getValue(context.getELContext());

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  }


  public int compare(Object[] o1, Object[] o2) {
    for (int i = 0; i < comparators.length; i++) {
      Comparator comparator = comparators[i];
      int c = comparator.compare(o1[i], o2[i]);
      if (c != 0) {
        return c;
      }
    }
    return 0;

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      if (actual.size() == 0) return;
      Comparator rawComparator = comparator;
      if (actual.size() == 1) {
        // Compare unique element with itself to verify that it is compatible with comparator (a ClassCastException is
        // thrown if not). We have to use a raw comparator to compare the unique element of actual ... :(
        rawComparator.compare(actual.get(0), actual.get(0));
        return;
      }
      for (int i = 0; i < actual.size() - 1; i++) {
        // List is sorted in comparator defined order if current element is less or equal than next element
        if (rawComparator.compare(actual.get(i), actual.get(i + 1)) > 0)

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        rawComparator.compare(actual.get(0), actual.get(0));
        return;
      }
      for (int i = 0; i < actual.size() - 1; i++) {
        // List is sorted in comparator defined order if current element is less or equal than next element
        if (rawComparator.compare(actual.get(i), actual.get(i + 1)) > 0)
          throw failures.failure(info, shouldBeSortedAccordingToGivenComparator(i, actual, comparator));
      }
    } catch (ClassCastException e) {
      throw failures.failure(info, shouldHaveComparableElementsAccordingToGivenComparator(actual, comparator));
    }

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            // compare by value first
            for(int d = 0; d < aEffectiveLength && d < bEffectiveLength; d++) {
                Comparator comparator = format.getComparator(d);
                if (comparator == null) return 0;
                int result = comparator.compare(a.path.get(d), b.path.get(d));
                if(result != 0) return result;
            }


            // and path length second
            return aEffectiveLength - bEffectiveLength;

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     *     then depth 3 corresponds to the element <code>yarmo.mp4</code>.
     */
    private boolean valuesEqual(int depth, E a, E b) {
        Comparator comparator = format.getComparator(depth);
        if (comparator != null) {
            return comparator.compare(a, b) == 0;
        } else {
            return GlazedListsImpl.equal(a, b);
        }
    }

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                // compare by value first
                for(int d = 0; d < aPathLength && d < bPathLength; d++) {
                    Comparator comparator = format.getComparator(d);
                    if (comparator == null) return 0;
                    int result = comparator.compare(a.get(d), b.get(d));
                    if(result != 0) return result;
                }


                // and path length second
                return aPathLength - bPathLength;

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     * Tests that comparison by property works.
     */
    public void testCompare() {
        Comparator comparator = GlazedLists.beanPropertyComparator(Position.class, "position", new String[0]);


        assertTrue(comparator.compare(new Position(4), new Position(1)) > 0);
        assertTrue(comparator.compare(new Position(1), new Position(4)) < 0);
        assertTrue(comparator.compare(new Position(3), new Position(3)) == 0);
    }


    /**

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     */
    public void testCompare() {
        Comparator comparator = GlazedLists.beanPropertyComparator(Position.class, "position", new String[0]);


        assertTrue(comparator.compare(new Position(4), new Position(1)) > 0);
        assertTrue(comparator.compare(new Position(1), new Position(4)) < 0);
        assertTrue(comparator.compare(new Position(3), new Position(3)) == 0);
    }


    /**
     * Tests that the equals() method of the comparator works.

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    public void testCompare() {
        Comparator comparator = GlazedLists.beanPropertyComparator(Position.class, "position", new String[0]);


        assertTrue(comparator.compare(new Position(4), new Position(1)) > 0);
        assertTrue(comparator.compare(new Position(1), new Position(4)) < 0);
        assertTrue(comparator.compare(new Position(3), new Position(3)) == 0);
    }


    /**
     * Tests that the equals() method of the comparator works.
     */

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