Converting a String to a Double, may I use Double constructor?

Hello,
I need to convert A String to a Double in my application.
Usually I use the Double.parseDouble(String) method that works fine.
But I have found one line in the code that use the Double class constructor: new Double(String). It has been observed that that constructor sometimes throws NullPointerException.
My question is, are theses two methods both good practices to do the convertion? Could threre be a multi-threading problem with the Double construtor?
I'm using JDK 1.3.1.
Here is a sample of stack trace:
bvsmgr: java.lang.NullPointerException
     at java.lang.FloatingDecimal.readJavaFormatString(Unknown Source)
     at java.lang.Double.valueOf(Unknown Source)
     at java.lang.Double.<init>(Unknown Source)
Thank you for all answers,
Florent.

But I have found one line in the code that use the
Double class constructor: new Double(String).
It has been observed that that constructor sometimes
throws NullPointerException.
My question is, are theses two methods both good
practices to do the convertion? Could threre be a
multi-threading problem with the Double construtor?Both methods are the same (they both use valueOf()), and if the c'tor throws an NPE, then only because you feed it null. parseDouble would do that, too.

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vinod_kmr wrote:
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