getClass().getProtectionDomain().getCodeSource().getLocation().getPath() Throw a null pointer exception

问题

I used this line of code in a Java class to retrieve a URI which i used to customize the ClassLoader:

String uri = getClass().getProtectionDomain().getCodeSource().getLocation().getPath();

Now the same line of code in an Android App in the MainActivity to be exact throw a null pointer exception.

Is there something special for Android development ? Thanks.

回答1:

getProtectionDomain() is not implemented in Android's version of Java

http://developer.android.com/reference/java/lang/Class.html#getProtectionDomain%28%29

Also, the ProtectionDomain class is marked as "Legacy security code; do not use."

http://developer.android.com/reference/java/security/ProtectionDomain.html

I assume this only exists in Android Java to maintain compilation compatibility.

来源：https://stackoverflow.com/questions/27790348/getclass-getprotectiondomain-getcodesource-getlocation-getpath-throw-a