nullpointerexception java

My exceptions-java. lang. NullPointerException, nullpointerexception I believe everyone is very familiar with this exception. I believe that everyone has met this exception in their programming career. During the development of 3.1 of colleges and universities, such errors were thrown out again. This is a small bug, but when it comes to it, it will make you sick

NullPointerException org. apache. commons. digester. Digester. getXMLReader (Digester. java: 1058), father of java Http://pwu-developer.blogspot.com/2010/01/nullpointerexception.html MavenIs great build tool making it easy to fetch all the library dependencies for a particle build. But what happens when you 've got an application that uses wide variety of librari

Analysis of Java NULL pointer exceptions (1) The Java language has an "exception mechanism" to handle special cases in the program. For example, if the divisor is zero, it is an "exception ".The NULL pointer exception java. Lang. nullpointerexception is a common exception. Let's talk about its analysis method.When the

Java. lang. NullPointerException:1: java. lang. Double. parseDoubleJava codeJava. lang. NullPointerExceptionSun. misc. FloatingDecimal. readJavaFormatString (FloatingDecimal. java: 991)Java. lang. Double. parseDouble (Double. java

The following lists the NullPointerException that often occurs when we learn java and its solutions. 1. Null Pointer Error java. lang. nullPointerException uses the Basic JAVA data type. The value of the variable is either the default value. If no value is assigned to the va

ZendStudioforEclipse's java. lang. NullPointerException solution. Of course, this item is very memory-consuming and will not be recommended for configuration. recently, I found that this error occurs when ZendStudioforEclipse is enabled after the PHP project is created. Aninterna is very memory-consuming, and it is not recommended if the configuration is almost complete. Recently, this error occurs when Ze

The exception of the null pointer is disgusting, I am afraid is the actual application of the most frequently occurring anomalies, the following is how to avoid nullpointerexception appearance of the technique Before using an object, it is best to know if they are possible null, and if not, use the IF statement to determine whether to use an object, or to traverse a collection, you need to make sure that they are non-empty. It's a rule that w

If it is reproduced, please describe the source! Http://blog.csdn.net/xukunddp I was frustrated when I wrote my blog in the previous article. Although I knew the steps for installing Aptana, the results were not satisfactory. There were still some problems with using Aptana, which were not solved by many people on the Internet. The first problem is that myeclipse cannot be started every time it is opened. You have to delete Org. eclipse. update or Org. eclipse. the osgi folder can be used t

empty string, it is a null object .), The println method of the out object cannot directly operate on the null object. Therefore, the JSP page where code segment 1 is located will throw a "java. lang. NullPointerException" exception.Even if the Object may be empty, some methods of java. lang. Object or Object itself, such as toString () and equals (Obj

Java. lang. NullPointerException, pointerexception when listView. getChildAt (I) BaseAdapter returns the component that can display the number of items on the current screen. Therefore, it uses listView. getChildAt (I ); The returned result is a widget that can be displayed on the current screen. You cannot use the listView. getChildAt (I) method to retrieve widgets other than those that can be displayed on

JsonMappingException: (was java. lang. NullPointerException)An exception is reported when java objects are serialized using jackson: com.fasterxml.jackson.databind.JsonMappingException: (was java.lang.NullPointerException) (through reference chain: com.chanjet.gov.Student["age"]) at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingEx

Today, when I was working on struts, I encountered the java. Lang. nullpointerexception: module 'null' not found error. I was depressed for a long time, The Web. xml file is not configured./WEB-INF/struts-config2.xml If this problem occurs, try this method! It is inconvenient to change eclipse, and it is inconvenient to find the struts plug-in 3.1.2. I still think JBuilder is good...

When any method is called for a null pointer in Java, a null pointer exception (java. lang. NullPointerException) is thrown ). Null Pointer exceptions are definitely the most difficult to find and debug in Java, and you will never get any useful debugging information. Summarized as follows through daily summary and onl

Error series for Android development (1), java. lang. NullPointerException, at android. widget. ListView. setupChild, appwidgetlistview Problem description: The Running code reports a null pointer error, java. lang. NullPointerException, at Android. widget. ListView. setupChild Problem location: The listview control re

Org. w3c. dom. ls. LSException: java. lang. NullPointerException, Chinese programming Operating Environment: OS: WIN 10.0.14393 x64 family Edition JDK: JavaSE 1.5.0 _ 20 i586 Tomcat: 6.0.48 win32 ----------------------------------------------------------------- Procedure: Run startup. bat to start Tomcat. ----------------------------------------------------------------- Exception information: Org. w3c. dom.

(Fileutil.java:365) at Org.apache.hadoop.fs.FileUtil.copy (Fileutil.java:338) at Org.apache.hadoop.fs.FileUtil.copy (Fileutil.java:289) at Org.apache.hadoop.fs.FileSystem.copyToLocalFile (Filesystem.java:1970) at Org.apache.hadoop.fs.FileSystem.copyToLocalFile (Filesystem.java:1939) at Org.apache.hadoop.fs.FileSystem.copyToLocalFile (Filesystem.java:1915) at Hadoop.downFile.downloadFileorDirectoryOnHDFS (Downfile.java: in) at Hadoop.downFile.main (Downfile.java: A)Solution: Change Fs.copytoloca

Severe: exception starting filter struts2 Java. Lang. nullpointerexception At com. opensymphony. xwork2.util. filemanager $ filerevision. needsreloading (filemanager. Java: 209) At com. opensymphony. xwork2.util. filemanager. fileneedsreloading (filemanager. Java: 60) At com. opensymphony. xwork2.config. providers. xml

A small struts2 program debugging fails after devmodel is changed to true, Severe: exception starting filter struts2Java. Lang. nullpointerexceptionAt com. opensymphony. xwork2.util. filemanager $ filerevision. needsreloading (filemanager. Java: 209)At com. opensymphony. xwork2.util. filemanager. fileneedsreloading (filemanager. Java: 60)At com. opensymphony. xwork2.config. providers. xmlconfigurationprov

Lab environment: JDK 1.6, Axis2-1.3, using SSL/TLS (one-way/two-way authentication), Tomcat 5.5/glassfish v2 When you use SSL/TLS to access the Web Service of axis2, the following error occurs:Exception in thread "Main" org. Apache. axis2.axisfault: Java. Lang. nullpointerexception This error is caused by the use of transportsession in the created web service-in service. xml:Transportsession">For solution

ZendStudioforEclipse6.x can be regarded as the best php ide. of course, this item is very memory-consuming and will not be recommended for configuration. Recently, this error occurs when Zend Studio for Eclipse is enabled after the PHP project is created. An internal error occurred during: "Building PHP projects ..." Java. lang. NullPointerException Annoying. PHP projects will stop building after