added class to support reference conversion A1 = 0,0 B1 = 0,1

git-svn-id: https://svn.apache.org/repos/asf/jakarta/poi/trunk@352531 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/hssf/util/ReferenceUtil.java

@@ -0,0 +1,80 @@
+/*
+ * ReferenceUtil.java
+ *
+ * Created on April 28, 2002, 1:09 PM
+ */
+
+package org.apache.poi.hssf.util;
+
+/**
+ * Handles conversion between A1= 0,0 (cell ref to numeric conversion)
+ * @author  Andrew C. Oliver (acoliver at apache dot org)
+ */
+public class ReferenceUtil {
+
+    /** You don't neeed to construct this */
+    private ReferenceUtil() {
+    }
+    
+    /**
+     * takes in a cell reference string A1 for instance and returns an integer
+     * array with the first element being the row number and the second being 
+     * the column number, all in 0-based base 10 format.
+     *
+     * @return xyarray row and column number
+     */
+    public static int[] getXYFromReference(String reference) {
+           int[] retval = new int[2];
+           String[] parts = seperateRowColumns(reference);           
+           retval[1] = convertColStringToNum(parts[0]);
+           retval[0] = Integer.parseInt(parts[1]);
+           return retval;
+    }
+    
+    /**
+     * takes in a column reference portion of a CellRef and converts it from 
+     * ALPHA-26 number format to 0-based base 10.
+     */
+    private static int convertColStringToNum(String ref) {
+        int len = ref.length();
+        int retval=0;
+        int pos = 0;
+        for (int k = ref.length()-1; k > -1; k--) {
+            char thechar = ref.charAt(k);
+            if ( pos == 0) {
+                retval += (Character.getNumericValue(thechar)-9);
+            } else {
+                retval += (Character.getNumericValue(thechar)-9) * (pos * 26);
+            }
+            pos++;
+            //System.out.println(val);
+        }
+        return retval-1;
+    }
+    
+    
+    /**
+     * Seperates the row from the columns and returns an array.  Element in
+     * position one is the substring containing the columns still in ALPHA-26
+     * number format.
+     */
+    private static String[] seperateRowColumns(String reference) {
+        int loc = 0; // location of first number
+        String retval[] = new String[2];
+        int length = reference.length();
+        
+        char[] chars = reference.toCharArray();
+        
+        for (loc = 0; loc < chars.length; loc++) {
+            if (Character.isDigit(chars[loc])) {
+                break;
+            }
+        }
+        
+        retval[0] = reference.substring(0,loc);
+        retval[1] = reference.substring(loc);
+        System.out.println("PART1=="+retval[1]);        
+        return retval;
+    }
+    
+}