Comparison of Exception Handling in C++ and Java

In C++ and Java, keywords like try,catch and throw for exception handling are same,their meaning is also same but exception handling in C++ and Java differ in many ways.

1)In Java only instances of subclasses of Throwable class i.e only throwable objects can be thrown as exception but in C++ any types like primitives,pointers etc can be thrown as exception.

Program that will work in C++ but not in Java.

#include <iostream>
using namespace std;
int main() 
{
   int a = -1;    
   try 
   {

      if( a < 0 )
      {
         throw x;
      }   
   }
   catch (int x ) 
   {

      cout << "Exception occurred:value thrown is " << x << endl;
   }
   getchar();
   return 0;
}

Output:

Exception occurred: value thrown is -1

2)In Java to catch all kind of Exception we catch Exception object e.g catch(Exception e) but in C++ a catch all is used to catch any kind of exception.

3)In Java there are two kinds of exceptions checked and unchecked but in C++ all exceptions are unchecked.

4)A block called finally is executed after try catch block is executed mostly to do cleanup work.In C++ there is no such block.

Example to demonstrate finally block in Java.

class Demo extends Exception 
{ 
}

class Main {


 public static void main(String args[]) {

      try 
      {
         throw new Demo();
      }
      catch(Demo d) 
      {
         System.out.println("Got the Demo Exception");
      }
      finally 
      {
         System.out.println("Inside finally block ");
      }
  }
}

Output

Got the Demo Exception
Inside finally block

5)In Java,throws keyword is used to list expected exceptions that a function can throw. In C++, there is no throws keyword, throw keyword is used instead to list expected keyword to be thrown.