Why is my Java code showing an incorrect time when converting to a specific timezone, and how can I fix it?

Date and Time Conversion to Specific Timezone in Java

In an attempt to convert the current system date and time to a specific timezone, you encountered a discrepancy between the expected output and the actual time in the desired timezone. To address this issue, we'll delve into the code you provided and identify the potential causes of the time difference.

The code uses the Calendar and SimpleDateFormat classes to handle date and time operations. You set the current time to currentdate and format it as a string using the formatter object. Then, you create a TimeZone object for the target timezone (CST in your case) and set it as the timezone for the formatter. Finally, you parse the formatted date string to obtain the resulting date in the specified timezone.

The discrepancy arises because the formatter formats the date in the local timezone before converting it to the target timezone. To account for this, you must explicitly adjust the time by adding or subtracting the offset difference between the local timezone and the target timezone.

Here's an updated code snippet that should provide the correct time conversion:

<code class="java">// Create a calendar and set it to the local timezone
Calendar calendar = Calendar.getInstance();
TimeZone fromTimeZone = calendar.getTimeZone();

// Create a calendar for the target timezone
TimeZone toTimeZone = TimeZone.getTimeZone("CST");

// Convert the current time to the local timezone
calendar.setTimeZone(fromTimeZone);
calendar.add(Calendar.MILLISECOND, fromTimeZone.getRawOffset() * -1);
if (fromTimeZone.inDaylightTime(calendar.getTime())) {
    calendar.add(Calendar.MILLISECOND, calendar.getTimeZone().getDSTSavings() * -1);
}

// Convert the time to the target timezone
calendar.add(Calendar.MILLISECOND, toTimeZone.getRawOffset());
if (toTimeZone.inDaylightTime(calendar.getTime())) {
    calendar.add(Calendar.MILLISECOND, toTimeZone.getDSTSavings());
}

// Get the final date and time in the target timezone
Date theResult = calendar.getTime();

System.out.println("The current time in India is  :: " + currentdate.getTime());
System.out.println("The date and time in :: " + toTimeZone.getDisplayName() + " is ::" + theResult);</code>

By adjusting the time according to the timezone offsets, you should now obtain the correct date and time in the specified timezone.

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