IDEMPIERE-1200 Check consistency of IBAN

org.adempiere.base/src/org/compiere/model/MBankAccount.java

@@ -21,6 +21,8 @@ import java.util.Properties;
 
 import org.compiere.util.CCache;
 import org.compiere.util.Env;
+import org.compiere.util.IBAN;
+import org.compiere.util.Util;
 
 
 /**
@@ -133,5 +135,23 @@ public class MBankAccount extends X_C_BankAccount
 			return insert_Accounting("C_BankAccount_Acct", "C_AcctSchema_Default", null);
 		return success;
 	}	//	afterSave
+	
+	protected boolean beforeSave (boolean newRecord)
+	{
+		if (!Util.isEmpty(getIBAN())) {
+			setIBAN(getIBAN().trim().replace(" ", ""));
+			try {
+				if (!IBAN.isCheckDigitValid(getIBAN())) {
+					log.saveError("Error", "IBAN is invalid");
+					return false;
+				}
+			} catch (Exception e) {
+				log.saveError("Error", "IBAN is invalid");
+				return false;
+			}
+		}
+
+		return true;
+	}
 
 }	//	MBankAccount

org.adempiere.base/src/org/compiere/util/IBAN.java

@@ -0,0 +1,67 @@
+package org.compiere.util;
+
+import java.math.BigInteger;
+
+import java.util.ResourceBundle;
+
+public class IBAN {
+    /**
+     * Determines if the given IBAN is valid based on the check digit.
+     * To validate the checksum:
+     * 1. Check that the total IBAN length is correct as per the country. If not, the IBAN is invalid.
+     * 2. Move the four initial characters to the end of the string.
+     * 3. Replace the letters in the string with digits, expanding the string as necessary, such that A=10, B=11 and Z=35.
+     * 4. Convert the string to an integer and mod-97 the entire number.
+     * If the remainder is 1 you have a valid IBAN number.
+     * @param iban
+     * @return boolean indicating if specific IBAN has a valid check digit
+     */
+    public static boolean isCheckDigitValid(String iban) {
+        if (null == iban) return false;
+        
+        int validIBANLength = getValidIBANLength(iban);
+        if (validIBANLength < 4) return false;
+        if (iban.length() != validIBANLength) return false;
+        
+        BigInteger numericIBAN = getNumericIBAN(iban, false);
+
+        int checkDigit = numericIBAN.mod(new BigInteger("97")).intValue();
+        return checkDigit == 1;
+    }
+    
+    /**
+     * Using the IBAN.properties file gets the valid fixed length value for a country code.
+     * Only uses the first 2 characters of the given string.
+     * @param countryCode
+     * @return
+     */
+    public static int getValidIBANLength(String countryCode) {
+        String code = countryCode.substring(0,2).toUpperCase();
+        String length = ResourceBundle.getBundle(IBAN.class.getCanonicalName()).getString("length."+code);
+        if (length == null) return -1;
+        return Integer.valueOf(length).intValue();
+    }
+    
+    private static BigInteger getNumericIBAN(String iban, boolean isCheckDigitAtEnd) {
+        String endCheckDigitIBAN = iban;
+        if (!isCheckDigitAtEnd) {
+            //Move first four characters to end of string to put check digit at end
+            endCheckDigitIBAN = iban.substring(4) + iban.substring(0, 4);
+        }
+        StringBuffer numericIBAN = new StringBuffer();
+        for (int i = 0; i < endCheckDigitIBAN.length(); i++) {
+            if (Character.isDigit(endCheckDigitIBAN.charAt(i))) {
+                numericIBAN.append(endCheckDigitIBAN.charAt(i));
+            } else {
+                numericIBAN.append(10 + getAlphabetPosition(endCheckDigitIBAN.charAt(i)));
+            }
+        }
+        
+        return new BigInteger(numericIBAN.toString());
+    }
+
+    private static int getAlphabetPosition(char letter) {
+        return Character.valueOf(Character.toUpperCase(letter)).compareTo(Character.valueOf('A'));
+    }
+
+}

org.adempiere.base/src/org/compiere/util/IBAN.properties

@@ -0,0 +1,45 @@
+# IBAN related properties. Includes IBAN lengths for different countries
+length.AD=24
+length.AT=20
+length.BE=16
+length.BA=20
+length.BG=22
+length.CH=21
+length.CY=28
+length.CZ=24
+length.DE=22
+length.DK=18
+length.EE=20
+length.ES=24
+length.FO=18
+length.FI=18
+length.FR=27
+length.GB=22
+length.GI=23
+length.GL=18
+length.GR=27
+length.HU=28
+length.HR=21
+length.IE=22
+length.IS=26
+length.IT=27
+length.LI=21
+length.LT=20
+length.LU=20
+length.LV=21
+length.MA=24
+length.MC=27
+length.MK=19
+length.MT=31
+length.NL=18
+length.NO=15
+length.PL=28
+length.PT=25
+length.RO=24
+length.RS=22
+length.SE=24
+length.SI=19
+length.SK=24
+length.SM=27
+length.TN=24
+length.TR=26