If your object reference equals to null, NullPointerException will be throw.
Tinyumbrella java.lang.nullpointerexception code#
When your applications code requires String representation of object, avoid using the objects toString method. Otherwise, you can throw an IllegalArgumentException and notify the calling method that something is wrong with passed arguments. Continue with execution of method, only when arguments are properly check. However, if we invoke method from literal, execution flow continues normally: before executing the body of your own method, be sure to check its arguments for null values. For example, observe following case: above code snippet will throw a NullPointerException. Instead of invoking method from null object, consider invoking it from literal. However, they do not eliminate problems and programmers should always be careful while coding application.S very common case in applications execution code involves comparison between string variables and literal.S Literal may be String or an element of Enum. In the rest of this section, we will describe some techniques that deal with the aforementioned exception. Locate the method and line where the exception was caught and then, figure out which reference equals to Null in that specific line. Execution stack trace is provided by JVM, in order to enable debugging of application. Also, if an exception is made use information residing in exception stack trace. You must verify that the Pointer is not null, before you request method or field from the Object.
Notice that, when you declare reference variable, you are really creating a Pointer to Object. In order to avoid NullPointerException, ensure that all your objects are initialized properly, before you use them.
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