publicclassNullPointerExceptionExample{publicstaticvoidmain(String[]args){Stringmessage=null;// 1. 检查对象是否为空if(message!=null){System.out.println(message.length());}else{System.out.println("消息为空");}// 2. 使用Optional类Optional<String>optionalMessage=Optional.ofNullable(message);optionalMe...
In this article, we’ll cover the ten most common exceptions in Java, their causes, and their solutions. These exceptions account for over97% of all Java exceptions. Once you know how to handle them, you’ll be ready to tackle nearly any Java error that comes your way. Table of content...
1) To avoid NullPointerException we should remember one thing i.e. we must initialize all object references with specified values before using. publicvoid display(String str){if(str.equals("Java")){System.out.println("Java");}} In the above case,NullPointerExceptioncan occur if the paramete...
Having an unchecked exception thrown inside a static initializer will inevitably trigger theExceptionInInitializerErrorruntime error. Figure 3(a) shows how invoking theString::lengthmethod on a non-initializedStringvariable (whose value defaults tonull) throws theNullPointerException, which in turn trig...
>> Clickherefor more information about Exceptions in Java. SQLException In JDBC, we may get exceptions when we execute or create the query. Exceptions that occur due to the Database or Driver come under SQL Exception. Using Exception handling, we can handle the SQL Exception like we handle ...
1. Introduction to the Problem A Java program can stop the normal execution flow in the following case: Checked exception Unchecked exception Error Java compiler forces us to catch and handle the checked exceptions when we use a method that throws it. These checked exceptions are anticipated, for...
In Java, the java.lang.NullPointerException is a popular exception that is faced by programmers while working on web applications and programs. The error is raised when the code tries to access a reference variable that points to a null value. It can be
However, it’s not without its limitations. TheCollections.sort()method sorts in ascending order by default, and it can’t handle null values. If you try to sort a list with null values, it will throw aNullPointerException. Moreover, it may not work as expected with custom objects, unle...
Failing to check fornullbefore using the value of anIntegerobject may lead to aNullPointerException, a runtime exception in Java. By conscientiously checking fornull, developers can ensure the robustness and reliability of their code, preventing unexpected runtime errors and enabling the implementation...
java.lang.NullPointerException Example – How to handle Java Null Pointer Exception (with video) Try Catch Java Example Java Stack Example (with video) Online Java Compiler – What options are there What is null in Java 6. Download the Eclipse Project ...