what is null pointer exception

Write an android dialog box, click the button to get edittext inside the value, here has been reported null pointer exception, studied for a long time finally solved.Exceptions are as follows:My original code:The update dialog box private void Updatedialog (final String id) {tablelayout updatemsg = (tablelayout) getlayoutinflater (). Inflate ( R.layout.updatemsg,

When initializing the default JSP page when running tomcat, the following message is displayed:Null Pointer Error [Java] View plaincopyprint? 1. At org. Apache. jsp. index_jsp. _ jspinit (index_jsp.java: 66) 1. At org. Apache. jsp. index_jsp. _ jspinit (index_jsp.java: 66) I think it may be an error during compilation .. Finally, a post is searched online. Th

The C + + language definition says that each pointer type has a special value----"NULL pointer".A null pointer is conceptually different from an uninitialized pointer. A

What you don't know -- it is best to assign a NULL value after the delete pointer in C ++ We all know that in C ++, all pointer variables declared with new must be deleted. Unless you fully use smart pointers without worrying about memory leaks. If you are from the C Sharp

Null Pointer exception is the most common and annoying exception. This topic describes how to avoid NULL pointer exceptions. First, let's look at the following example private Boolean i

Atitit avoids NULL pointer exception solution, while atitit avoids pointer Atitit solution to avoid NULL pointer exceptions 1. Null Question 1 2. Force distinguish between common refe

Java.lang.reflect.InvocationTargetException and with null pointer exceptions at the same time,This error is derived from the implementation of the user automatic login function: Login interface, when entered user name and password, not checked automatic login button, the results in Userservlet implementation method, as long as there

Listen to the teacher said, in the later study most of the anomalies are null pointer anomalies. So take a little time to play the game to check what is a null pointer exception One: T

.Http11Processor.process (http11processor.java:861)At Org.apache.coyote.http11.http11protocol$http11connectionhandler.process (http11protocol.java:612)At Org.apache.tomcat.util.net.jioendpoint$worker.run (jioendpoint.java:503)At Java.lang.Thread.run (thread.java:662)The error is that my front-end interface input values cannot be passed to the background, so the background cannot be retrieved.Code positioningTo this line, but there

references. Therefore, the Null Pointer Error in C/C ++ is no longer exposed, but a running-level exception-"nullpointerexception ". From this point on, it is a benefit of Java.Josha Bloch mentioned in objective Java that the function returns an array. If no return value ex

A null pointer exception (JAVA.LANG.NULLPOINTEREXCEPTION) is thrown when any method is called in Java for a pointer with a value of NULL. Null