In this post we’ll discuss about java.lang.NoClassDefFoundError and how to fix it. When is NoClassDefFoundError in Java thrown NoClassDefFoundError in Java is thrown when a class is present at compile time but at runtime when the JVM or a ClassLoader instance tries to load in the definition of a class…
ClassNotFoundException in Java is thrown if an application tries to load a class but the class with the specified name is not found. java.lang.ClassNotFoundException ClassNotFoundException in Java is a checked exception which means it subclasses from Exception class (not from RuntimeException). This exception is thrown if you try to load…
In this post we’ll discuss about java.lang.UnsupportedClassVersionError and how to fix it. When is UnsupportedClassVersionError in Java thrown UnsupportedClassVersionError is thrown when the Java Virtual Machine attempts to read a class file whose major and minor version numbers are not supported by the current JVM version. To understand it better…
In this post we’ll discuss about java.util.InputMismatchException and how to fix it. InputMismatchException is thrown when you are trying to read tokens through a Scanner class instance and the input retrieved doesn’t match the pattern for the expected type. InputMismatchException in Java Scanner class in Java can be used to…
ClassCastException in Java is thrown if you try to cast an object to a type of which it is not an instance. For example consider the following code- Object l = Long.valueOf(“120”); System.out.println(l); //120 Number n = (Number)l; System.out.println(n); // 120 Here we have a reference of Long stored in…
While working on and running a Java application you may come across any of these two errors related to memory, StackOverflowError and OutOfMemoryError. In this post we’ll see the differences between StackOverflowError and OutOfMemoryError in Java. Table of contents StackOverflowError in Java OutOfMemoryError in Java StackOverflowError Vs OutOfMemoryError in Java…
Java 7 onward a new feature try-with-resources is available for automatic resource management. With this feature, try-with-resources in Java, one or more resources are declared with the try statement itself. The try-with-resources statement ensures that the declared resources are closed automatically at the end. Here resource is an object that…
Differences among final, finally and finalize in Java is an important interview question. One reason being, these words sound similar and another is it gives an interviewer a chance to branch out to many other areas. From final you can go on to talk about inheritance or method overriding. From…
In Java exception handling there are lots of exception classes that can be used for handling exceptions. Though some times you may not find an appropriate exception class that clearly represents the exception thrown from your code, in such scenario you may choose to create your own custom exception class.…
When an exception is thrown in a code the normal execution flow of the method is disrupted and that may result in opened resources never getting closed. In such scenarios you do need a clean up mechanism that’s where finally block in Java helps. For Example, suppose in a method…
