What’s the C++ version of Java’s ArrayList
Use the std::vector class from the standard library.
java
Error java.lang.OutOfMemoryError: GC overhead limit exceeded
This message means that for some reason the garbage collector is taking an excessive amount of time (by default 98% of all CPU time of the process) and recovers very little memory in each run (by default 2% of the heap). This effectively means that your program stops doing any progress and is busy running … Read more
What is the reason behind “non-static method cannot be referenced from a static context”? [duplicate]
You can’t call something that doesn’t exist. Since you haven’t created an object, the non-static method doesn’t exist yet. A static method (by definition) always exists.
Error parsing data org.json.JSONException: Value
I want to make a login registration system with my app but is not working properly. Here the code where I think I’ve got an error. PHP LOGIN SCRIPT : LoginActivity : JSONParser Class: When I want to login with the right username and password it’s working but if I put right username and wrong … Read more
How to uninstall Eclipse?
There is no automated uninstaller. You have to remove Eclipse manually by deleting some directories and files. Note: I use Unix style paths in this answer but the locations should be the same on Windows or Unix systems, so ~ refers to the user home directory even on Windows. Why is there no uninstaller? According … Read more
How to remove the last character from a string?
replace will replace all instances of a letter. All you need to do is use substring():
How can I convert IPV6 address to IPV4 address?
While there are IPv6 equivalents for the IPv4 address range, you can’t convert all IPv6 addresses to IPv4 – there are more IPv6 addresses than there are IPv4 addresses. The only sane way around this issue is to update your application to be able to understand and store IPv6 addresses.
Difference between Inheritance and Composition
They are absolutely different. Inheritance is an “is-a” relationship. Composition is a “has-a”. You do composition by having an instance of another class C as a field of your class, instead of extending C. A good example where composition would’ve been a lot better than inheritance is java.util.Stack, which currently extends java.util.Vector. This is now … Read more
Exception in thread “main” java.lang.Error: Unresolved compilation problems
Your problem is in this line: Message messageObject = new Message ();This error says that the Message class is not known at compile time. So you need to import the Message class. Something like this: Check this out. http://docs.oracle.com/javase/tutorial/java/package/usepkgs.html
Reason for”Exception in thread “AWT-EventQueue-0″ java.lang.NullPointerException”
This question already has answers here: What is a NullPointerException, and how do I fix it? (12 answers) Closed 4 years ago. i am creating to create a hotel reservation system ,but evey time i run my project i recieve “Exception in thread “AWT-EventQueue-0″ java.lang.NullPointerException” and i have not been able to find why . … Read more