java.time
The legacy date-time API (java.util date-time types and their formatting API, SimpleDateFormat) are outdated and error-prone. It is recommended to stop using them completely and switch to java.time, the modern date-time API*.
Demo using modern date-time API:
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.time.format.DateTimeFormatterBuilder;
import java.time.format.TextStyle;
import java.util.Locale;
public class Main {
    public static void main(String args[]) {
        String dateStr = "Mon Mar 31 2014 00:00:00 GMT+0530 (India Standard Time)";
        
        DateTimeFormatter dtf = new DateTimeFormatterBuilder()
                                .parseCaseInsensitive()
                                .appendPattern("EEE MMM d u H:m:s")
                                .appendLiteral(' ')
                                .appendZoneId()
                                .appendPattern("X")
                                .appendLiteral(" (")
                                .appendZoneText(TextStyle.FULL)
                                .appendLiteral(')')
                                .toFormatter(Locale.ENGLISH);
        
        ZonedDateTime zdt = ZonedDateTime.parse(dateStr, dtf);
        
        System.out.println(zdt);
    }
}
Output:
2014-03-31T00:00+05:30[Asia/Kolkata]
For any reason, if you need an object of java.util.Date from this object of ZonedDateTime, you can so as follows:
Date date = Date.from(zdt.toInstant());
Learn more about the the modern date-time API* from Trail: Date Time.
* For any reason, if you have to stick to Java 6 or Java 7, you can use ThreeTen-Backport which backports most of the java.time functionality to Java 6 & 7. If you are working for an Android project and your Android API level is still not compliant with Java-8, check Java 8+ APIs available through desugaring and How to use ThreeTenABP in Android Project.