--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/agent/src/share/classes/sun/jvm/hotspot/ui/table/TableModelComparator.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,126 @@
+/*
+ * Copyright 2002 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+package sun.jvm.hotspot.ui.table;
+
+import java.util.*;
+
+import javax.swing.table.TableModel;
+import javax.swing.event.TableModelEvent;
+
+/**
+ * A comparator which compares rows in a table model
+ */
+public abstract class TableModelComparator implements Comparator {
+
+    private boolean ascending;
+    protected TableModel model;
+
+    private int[] columns;
+
+    public TableModelComparator(TableModel model) {
+        this.model = model;
+
+        // XXX - Should actually listen for column changes and resize
+        columns = new int[model.getColumnCount()];
+        columns[0] = -1;
+    }
+
+    /**
+     * Add the column to the sort criteria
+     */
+    public void addColumn(int column) {
+        // Shift columns in the array
+        int[] tempArray = new int[model.getColumnCount()];
+        System.arraycopy(columns, 1, tempArray, 0, columns.length - 1);
+
+        columns = tempArray;
+        columns[0] = column;
+    }
+
+    /**
+     * Get the last column that was sorted
+     */
+    public int getColumn() {
+        return columns[0];
+    }
+
+    public void setAscending(boolean ascending) {
+        this.ascending = ascending;
+    }
+
+    public boolean isAscending() {
+        return ascending;
+    }
+
+    /**
+     * Implementation of the comparator method. A comparison is
+     * made for rows.
+     */
+    public int compare(Object row1, Object row2) {
+        for (int i = 0; i < columns.length; i++) {
+
+            Object o1 = getValueForColumn(row1, columns[i]);
+            Object o2 = getValueForColumn(row2, columns[i]);
+
+            // If both values are null, return 0.
+            if (o1 == null && o2 == null) {
+                return 0;
+            } else if (o1 == null) { // Define null less than everything.
+                return -1;
+            } else if (o2 == null) {
+                return 1;
+            }
+
+            int result = 0;
+
+            if (o1 instanceof Comparable) {
+                Comparable c1 = (Comparable)o1;
+                Comparable c2 = (Comparable)o2;
+
+                result = c1.compareTo(c2);
+            }
+
+            // XXX Should have some sort of provision for determininte
+            // if there is another way of comparing the objects.
+            // Perhaps we should add the requirement that all table
+            // values be Compabable.
+
+            if (result != 0) {
+                return ascending ? result : -result;
+            }
+        }
+        return 0;
+    }
+
+    /**
+     * Returns the value for the comparing object for the
+     * column.
+     *
+     * @param obj Row object that was passed into Comparator.
+     * @param column the column to retrieve
+     */
+    public abstract Object getValueForColumn(Object obj, int column);
+
+}