new comments are added after code review.

Author: ammajumd

README.md

@@ -182,12 +182,18 @@ Retry Pattern allows to retry sending a failed request and it will only work wit
 
 ## Changes
 
-Version Cybersource-sdk-java 6.2.6 (OCT,2017)
+Version Cybersource-sdk-java 6.2.6 (JAN,2018)
+_______________________________
+  1) Added certificateCacheEnabled optional feature. certificateCacheEnabled parameter is set to false (default is true), the p12 certificate of a merchant will be reloaded from filesystem every time a transaction is made.If the certificateCacheEnabled is true then only at the begining time certificate of a merchant will loaded from filesystem.
+  2) Intreduced a new feature to check merchant .p12 certificate file validity at run time.If it is not valid and replaced at runtime then SDK will be able to reload the new certificate data into cache.
+  3) Changed clientLibrary version to 6.2.6;
+
+Version Cybersource-sdk-java 6.2.5 (OCT,2017)
 _______________________________
   1) Merchant cert to be read from JAVA key store. Flag is added to enable reading cert from Java keystore.
   2) Added Custom HttpClient feature. Merchants can use there own http client instead of defaults which comes with SDK.
   3) Http Client connection reuse issue.
-  4) Changed clientLibrary version to 6.2.6; in 6.2.4 release it was missed. So, in 6.2.4 release, clientLibrary version was      pointing to 6.2.3.
+  4) Changed clientLibrary version to 6.2.5; in 6.2.4 release it was missed. So, in 6.2.4 release, clientLibrary version was      pointing to 6.2.3.
 _______________________________  
 Version Cybersource-sdk-java 6.2.4 (Dec 15, 2016)
 _______________________________

java/src/main/java/com/cybersource/ws/client/Identity.java

@@ -116,6 +116,11 @@ public Identity(MerchantConfig merchantConfig,X509Certificate x509Certificate, P
         setUpMerchant();
     }
 
+    /**
+     * Replace of merchant certificate not happened at runtime then isValid method will return true and certificate reload will not happen.
+     * But replace of merchant certificate happened at at runtime then isValid method will return false and certificate reload will happen.
+    */
+    
 	public boolean isValid(File keyFile) {
 
 		boolean changeKeyFileStatus=(this.lastModifiedDate == keyFile.lastModified());

java/src/main/java/com/cybersource/ws/client/SecurityUtil.java

@@ -67,6 +67,13 @@ private static void initKeystore() throws KeyStoreException, CredentialException
     /**
      * Method loads the Merchant P12 key.
      *  IMPORTANT :This change is made based on the assumptions that at point of time , a merchant will have only one P12 Key
+     *
+     *CertificateCacheEnabled : If it is true then only first time merchant p12 file will be loaded.
+     *							If it is false then every time merchant p12 file will be loaded.
+     *
+     *isValid() method checks : If this method returns true that means existing certificate is valid and reload of merchant p12 file will not happen.                            
+     *						  : If method returns false that means existing certificate is not valid and reload of new merchant p12 file will happen.
+     *    
      * @param merchantConfig - Merchant Config
      * @param logger - logger instance
      * @throws SignException - Signature exception
@@ -76,10 +83,7 @@ private static void initKeystore() throws KeyStoreException, CredentialException
      * @throws CredentialException
      */
     public static void loadMerchantP12File(MerchantConfig merchantConfig, Logger logger) throws SignException, SignEncryptException, ConfigException {
-        
-        // Load the KeyStore and get the signing key and certificate
-        // This change is made based on the assumptions that at point of time , a merchant will have only one P12 Key
-       
+               
         Identity identity=identities.get(merchantConfig.getMerchantID());
         if(!merchantConfig.isCertificateCacheEnabled() || identity == null || !(identity.isValid(merchantConfig.getKeyFile()))){
             try {

zip/README

@@ -199,6 +199,12 @@ Mock objects library for java
 
 ##Changes
 
+Version Cybersource-sdk-java 6.2.6 (JAN,2018)
+_______________________________
+  1) Added certificateCacheEnabled optional feature. certificateCacheEnabled parameter is set to false (default is true), the p12 certificate of a merchant will be reloaded from filesystem every time a transaction is made.If the certificateCacheEnabled is true then only at the begining time certificate of a merchant will loaded from filesystem.
+  2) Intreduced a new feature to check merchant .p12 certificate file validity at run time.If it is not valid and replaced at runtime then SDK will be able to reload the new certificate data into cache.
+  3) Changed clientLibrary version to 6.2.6;
+
 Version Cybersource-sdk-java 6.2.5 (OCT,2017)
 _______________________________
   1) Merchant cert to be read from JAVA key store. Flag is added to enable reading cert from Java keystore.