[WW-2567] DateTimePicker makes non-thread-safe use of SimpleDateFormat

• Type: Bug
• Status: Closed
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 2.0.11.1
• Fix Version/s: 2.0.12
• Component/s: Core Actions
• Flags: Patch
• Assignee: James Mitchell
• Reporter: Mike Calmus
• Created: 26/Mar/08 15:55
• Updated: 28/Oct/12 22:08
• Resolved: 20/May/08 18:02

Description

DateTimePicker has an internal static final instance of a SimpleDateFormat it uses to format date strings.

However, according to the SimpleDateFormat JavaDoc:
Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Easy fix is to synchronize around all uses of the class.

Index: src/main/java/org/apache/struts2/components/DateTimePicker.java
===================================================================
— src/main/java/org/apache/struts2/components/DateTimePicker.java (revision 641326)
+++ src/main/java/org/apache/struts2/components/DateTimePicker.java (working copy)
@@ -294,20 +294,25 @@
return null;

if(obj instanceof Date) {
+ synchronized (RFC3339_FORMAT)

{ return RFC3339_FORMAT.format((Date) obj); + }

} else {
// try to parse a date
String dateStr = obj.toString();
if(dateStr.equalsIgnoreCase("today"))
+ synchronized (RFC3339_FORMAT)

{ return RFC3339_FORMAT.format(new Date()); - + }

try {
Date date = null;
if(this.displayFormat != null) {
SimpleDateFormat format = new SimpleDateFormat(
(String) getParameters().get("displayFormat"));
date = format.parse(dateStr);

• return RFC3339_FORMAT.format(date);
  + synchronized (RFC3339_FORMAT) { + return RFC3339_FORMAT.format(date); + }

  } else {
  // last resource to assume already in correct/default format
  return dateStr;