JAVA

throw io exception java

public static void foo() throws IOException {
    // some code here, when something goes wrong, you might do:
    throw new IOException("error message");
}

public static void main(String[] args) {
    try {
        foo();
    } catch (IOException e) {
        System.out.println(e.getMessage());
    }
}

in java how to throw exception from function

public void doChangePin(int oldPin, int pin) throws Exception {	//need to add throws followed by exception name
		if (oldPin == pinCode) {
			pinCode = pin;
		} else {
			throw new Exception("some message");	//throwing the exception by creating its new object
		}
	}

throw error java

throw new java.lang.Error("this is very bad");
throw new java.lang.RuntimeException("this is not quite as bad");

java throw an exception

public static void main(String[] args) {
	Scanner kb = new Scanner(System.in);
    System.out.println("Enter a number");
    try {
    	double nb1 = kb.nextDouble();
    	if(nb1<0)
        	throw new ArithmeticException();
        else System.out.println( "result : " + Math.sqrt(nb1) );
    } catch (ArithmeticException e) {
        System.out.println("You tried an impossible sqrt");
    }
}

throw and throws keyword in java

Throws keyword used for handling exceptions. 
  Where do you use it? Methods signature. 
 If you want to handling right away in selenium or Api use “throws” keyword.
Throw is creating an exception. Basically there are doing opposite. 
Where do you use it? We use it with in the block.

Java Exception handling using Java throw

class Main {
  public static void divideByZero() {

    // throw an exception
    throw new ArithmeticException("Trying to divide by 0");
  }

  public static void main(String[] args) {
    divideByZero();
  }
}

Java The Throw/Throws Keyword

//f a method does not handle a checked exception, the method must declare it using the throws keyword. The throws keyword appears at the end of a method's signature. 
One can throw an exception, either a newly instantiated one or an exception that you just caught, by using the throw keyword. 
Understand the difference between throws and throw keywords, throws is used to postpone the handling of a checked exception and throw is used to invoke an exception explicitly. 
Example
import java.io.*;
public class className {

   public void deposit(double amount) throws RemoteException {
      // Method implementation
      throw new RemoteException();
   }
   // Remainder of class definition
}

throw keyword in java

Generally JVM throws the exception and
we handle the exceptions by 
using try catch block. But there are
situations where we have to throw 
userdefined exceptions or runtime exceptions.
  In such case we use throw keyword 
to throw exception explicitly.

  Syntax : throw throwableInstance;

throw error java

throw new java.lang.Error("this is very bad");