how to create exception in java

When I was learning Java exception handling, I remember a few words about the handling of a parent-child exception. A subclass method can only throw an exception or its child exception that the parent class method throws, and the child class constructor must throw an

The difference between the checked exception and the unchecked exception in Java is described in detail. (1) Java exception hierarchy To understand the differences between checked Exception and unchecked

class and its subclasses represent run-time errors, which are typically thrown by Java virtual machines, and the JDK defines some error classes, such as Virtualmachineerror and OutOfMemoryError, The program itself cannot fix these errors. Generally do not extend the error class to create user-defined fault classes. The RuntimeException class represents an error in program code that is extensible and allows

How to make our exception handling flexible enough-we can create an exception class ourselves (common operations for all exceptions)In the user management system, the specific operation is as follows:1. Create a Userexception class2, find superclass, click Browse, select Java.lang.Exception, complete the creation3, ope

constructor with a string, this string will be used as an additional description for this exception object except for the type name.Why create your own exceptions? When Java built-in exceptions cannot explicitly describe the exceptions, you need to create your own exceptions. It should be noted that the only useful in

When Java programs violate Java semantic rules, the Java Virtual machine will represent errors that occur as an exception The violation of the semantic rules consists of two cases: One is a semantic check built into the Java class library, such as an array of bounds that thr

When doing a function of converting a string to integer today, it is found that Integer.parseinte () throws an exception numberformatexception.function integer.parseint (String) definition1 int parseint (String s) 2 Throws NumberFormatExceptionTest code: 1 public class Test 2 { 3 public static void main (string[] args) 4 { 5 Integer num = integer.parseint ("FF" 6 System.out.println (num); 7 } 8 }We know that a

Java-exception details, java-Details (1) Causes of exceptions Exception Handling can improve program robustness. The C language uses function return values to handle exceptions. disadvantages of this approach: 1. The returned value may conflict with the existing logic. 2. Poor code readability. The Execution Code is mi

---restore content starts---First of all, I am a small rookie, recently suddenly whim, want to study the Java exception and exception handling, a little bit of understanding, the birds do not want to ridicule ...Since we want to deal with exceptions and exceptions, we need to understand the anomalies first, so what is an exce