jdk浮点bug

If you are interested you can run the following code on your machine:

public class JavaRunHang {

public static void main(String[] args) {

            System.out.println("Test:");

            double d = Double.parseDouble("2.2250738585072012e-308");

            System.out.println("Value: " + d);

      }

}

Compile this program and run it; the program will hang.

public class JavaCompileHang {

public static void main(String[] args) {

            double d = 2.2250738585072012e-308;

            System.out.println("Value: " + d);

      }

}

And compiling the code above will get your IDE hang.

It turns out to be a security hole for both Sun JDK and Open JDK (http://security-tracker.debian.org/tracker/CVE-2010-4476). This can be used in DOS attack. I’m still seeing if this will affect our apps. Lucky that it's not Long.parseLong.

顺便说一点，我1.6的jdk，第一次被hang住以后，第二次再运行的话，编译（执行javac）就被hang住了，cpu飙升满了。