CodesJava

Easy learning with example program codes

Exception propagation in java


Exception propagation:

Exception propagation is a way of propagating exception from method to method. Let an exception occur in a method at the top of the call stack and if it is not caught then it propagates to previous method in the call stack, if it is not caught here then it again propagates to previous method in the call stack and so on until either it is caught or reach the bottom of the stack.

Example: Exception propagation in case of unchecked exception.

ExceptionPropagationExample1.java

/**
 * This program used to show the use of 
 * unchecked exception propagation.
 * @author codesjava
 */
class ArithmaticTest{
	/**
	 * This method is used to divide two integers.
	 * @param num1
	 * @param num2
	 * @author codesjava
	 */
	public void division(int num1, int num2) {
		//java.lang.ArithmeticException here 
                //and not caught hence propagate to method1.
		System.out.println(num1/num2);
	}
 
	public void method1(int num1, int num2) {
		//not caught here and hence propagate to method2.
		division(num1, num2);
	}
 
	public void method2(int num1, int num2){
		try{
			method1(num1, num2);
		}catch(Exception e){//caught exception here.
			System.out.println("Exception Handled");
		}
	}
}
 
public class ExceptionPropagationExample1 {
	public static void main(String args[]){
		//creating ArithmaticTest object
		ArithmaticTest obj =  new ArithmaticTest();
 
		//method call
		obj.method2(20, 0);
	}
}

Output:

Exception Handled

Download this example.

Example: Exception propagation in case of checked exception.

Note: Checked exceptions are not propagated in exception change.

ExceptionPropagationExample2.java

import java.io.IOException;
 
/**
 * This program used to show the use of 
 * checked exception propagation.
 * @author codesjava
 */
class Test{
 
	public void method3() {
		//compile time error here because 
                //checked exceptions can't be propagated.
		throw new IOException();
	}
 
	public void method1(){
		method3();
	}
 
	public void method2(){
		try{
			method1();
		}catch(Exception e){
			System.out.println("Exception Handled");
		}
	}
}
 
public class ExceptionPropagationExample2 {
	public static void main(String args[]){
		//creating Test object
		Test obj =  new Test();
 
		//method call
		obj.method2();
	}
}

Output:

Exception in thread "main" java.lang.Error: 
Unresolved compilation problem:
Unhandled exception type IOException
at com.codesjava.business.Test.method3
(ExceptionPropagationExample2.java:13)
at com.codesjava.business.Test.method1
(ExceptionPropagationExample2.java:17)
at com.codesjava.business.Test.method2
(ExceptionPropagationExample2.java:22)
at com.codesjava.business.ExceptionPropagationExample2.main
(ExceptionPropagationExample2.java:35)

Download this example.
 
Next Topic: Exception handling with method overriding in java.
Previous Topic: throws in java with example.

Related Topics:

Some important terms for Exception Handling.
Exception handling in java.
try and catch blocks in java with example.
Multiple catch blocks in java with example.
Nested try block in java with example.
Finally in java with example.
throw in java with example.
throws in java with example.
Exception propagation in java with example.
Exception handling with method overriding in java.
Custom exception in java with example.
Commonly used exception methods of Throwable class in java.

 

Core Java Tutorial

Programming language overview.
Overview of Java.
Java features
JVM architecture details.
JVM, JRE and JDK.
Java Coding Guidelines.
Some important definitions.
Variable and data types.
Hello world java program.
Core java examples programs.
Important Java Programs.
How to set permanent path in java?
OOPs Basics.
Object and Class in Java.
OOPs Principles/Concepts.
Abstraction in java.
Encapsulation in java.
Polymorphism in java.
Method overloading in java.
Method overriding in java.
Dynamic method dispatch.
Runtime polymorphism.
Association in java.
Inheritance in java.
Aggregation in java.
Command line arguments in java.
Command line argument program in eclipse.
Read input from command line using Scanner.
Java array programs
Java star pattern programs
Java number pattern programs
final in java.
Abstract class in java.
Interface in java.
Custom marker Interface in java.
Constructor in java.
Package in java.
Access modifier in java.
Static import in java.
Package class in java.
this in java.
Instance initialize block.
Anonymous block.
super in java.
Static in java.
final in java.
Java cloning deep and shallow
Shallow vs Clone copy
String handling in java.
String handling programs.
StringBuffer in java.
StringBuilder in java.
Exception Handling Tutorial.
Multithreading Tutoial.
Java input output stream tutorial.
Collections framework in java tutorial.
Collections framework programs.
Java Random class
Java annotations.
Java design principles.
Java 7 features
Java 8 features
Java networking tutorial
Java Reflection tutorial
Sign Up/ Sign In
Ask a Question


Industrial Training

We offers Placement Oriented Training on Java, Spring, JSF, Hibernate, PHP, AngularJS, Angular 4, PLSQL, Oracle BI Publisher etc. We also provides Online training, please mail us at hr@codesjava.com.

Development

We also provides the Development services for Website Development , Java Development, PHP Development, Android App Development etc. You can contact us on hr@codesjava.com.

Copyright © 2018 CodesJava DMCA.com Protection Status SiteMap Reference: Java Wiki