Deck 12: Exception Handling

Question 1

A(n) ____ statement is one that sends an Exception object out of a method so it can be handled elsewhere.

A) throw
B) catch
C) optional
D) assert

Answer 1

A

Question 2

When a program contains multiple ____ blocks, they are examined in sequence until a match is found for the type of exception that occurred.

A) throw
B) finally
C) catch
D) try

Answer 2

C

Question 3

The keyword catch followed by an Exception type in the method header is used when a method throws an exception that it will not catch but that will be caught by a different method.

Answer 3

False

Question 4

To use a method to its full potential, you must know the method name, return type, type and number of arguments required, and type and number of exceptions the method throws.

Question 5

Many developers believe that it is poor style for a method to throw more than ____ type(s) of exceptions.

A) one
B) two
C) three or four
D) eight or ten

Question 6

A catch block is a method that can be called directly and takes an argument that is some type of exception.

Question 7

____ represents the degree to which a system is resilient to stress, maintaining correct functioning.

A) Endurance
B) Robustness
C) Fault-tolerant
D) Strength

Question 8

When you have actions you must perform at the end of a try…catch sequence, you can use a ____ block.

A) finally
B) catch
C) throw
D) try

Question 9

The code within a finally block cannot execute if the preceding try block identifies an exception.

Question 10

Placing data conversion attempts in a try block allows you to handle potential data conversion errors caused by careless user entry.

Question 11

The ____ class represents more serious errors from which your program usually cannot recover.

A) Error
B) Throwable
C) Exception
D) Menu

Question 12

When an exception is a checked exception, client programmers are forced to deal with the possibility that an exception will be thrown.

Question 13

Unplanned exceptions that occur during a program's execution are also called execution exceptions.

Question 14

You can place as many statements as you need within a try block, and you can catch as many exceptions as you want.

Question 15

Since variables declared within a try or catch block are local to that block, the variable goes out of scope when the try or catch block ends.

Question 16

To create your own throwable Exception class, you must extend a subclass of Catchable.

Question 17

Some programmers refer to a catch block as a catch ____.

A) method
B) phrase
C) statement
D) clause

Question 18

The parent class of Error is ____.

A) Object
B) Exception
C) RuntimeError
D) RuntimeException

Question 19

What is the first program statement in a catch block?

A) the keyword catch
B) an opening curly brace
C) the keyword Exception
D) the statements that take the action you want to use to handle the error condition

Question 20

____ statements are program statements that can never execute under any circumstances.

A) Stagnant
B) Error
C) Unreachable
D) Exception

Question 21

If a method throws an exception that it will not catch but that will be caught by a different method, you must also use the keyword ____ followed by an Exception type in the method header.

A) finally
B) try
C) catch
D) throws

Question 22

A(n) ____ is a Java language feature that can help you detect logical errors that do not cause a program to terminate, but nevertheless produce incorrect results.

A) error checker
B) thread
C) assertion
D) throw statement

Question 23

The memory location known as the ____________________ is where the computer stores the list of method locations to which the system must return.

Question 24

The ____________________ class comprises less serious errors that represent unusual conditions that arise while a program is running and from which the program can recover.

Question 25

Any ____________________ block might throw an Exception for which you did not provide a catch block.

Question 26

Which of the following is NOT a component of a try block?

A) a closing curly brace
B) the keyword try
C) executable statements
D) a throw statement

Question 27

Programs would be less clear if you had to account for ____ exceptions in every method declaration.

A) unthrown
B) thrown
C) runtime
D) checked

Question 28

If you want to ensure that a user enters numeric data, you should use ____ techniques that provide the means for your program to recover from the mistake.

A) error-handling
B) looping
C) exception-handling
D) decision

Question 29

The Java compiler does not require that you catch or specify ____ exceptions.

A) checked
B) runtime
C) return
D) optional

Question 30

What is the correct syntax of an assert statement?

A) assert AssertionError : optionalErrorMessage
B) assert booleanExpression : optionalErrorMessage
C) assert stringExpression : optionalErrorMessage
D) assert booleanExpression = optionalErrorMessage

Question 31

When you catch an Exception object, you can call ____________________ to display a list of methods in the call stack so you can determine the location of the statement that caused the exception.

Question 32

____ exceptions are the type that programmers should anticipate and from which programs should be able to recover.

A) Unchecked
B) Runtime
C) Checked
D) Thrown

Question 33

When a constructor throws an exception, no object is constructed; its intended reference variable value will be ____.

A) final
B) null
C) negative
D) correct

Question 34

Assertions are meant to be helpful in the ____ stage of a program.

A) development
B) testing
C) production
D) modeling

Question 35

A(n) ____ clause is used in the method header so that applications that use your methods are notified of the potential for an exception.

A) throws
B) return
C) stack
D) exception

Question 36

In the case where a method might throw more than one exception type, you specify a list of potential exceptions in the method header by separating them with ____.

A) spaces
B) semicolons
C) commas
D) periods

Question 37

In order to use a variable both with a try or catch block and afterward, you must declare the variable before the ____ block begins.

A) catch
B) try
C) main
D) finally

Question 38

Which method constructor constructs a new exception with the specified detail message and cause?

A) Exception()
B) Exception(String message)
C) Exception(String message, Throwable cause)
D) Exception(Throwable cause)

Question 39

When you use a(n) ____ statement, you state a condition that should be true, and Java throws an AssertionError when it is not.

A) if
B) boolean
C) assert
D) exception

Question 40

If you create an object using Java's BigDecimal class, and then perform a division that results in a non-terminating decimal division such as 1/3, but specify that an exact result is needed, a(n) ____________________ is thrown.

Question 41

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
Should always be true if the program is working correctly

Question 42

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
Constructs a new exception with the specified detail message

Question 43

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
Object-oriented techniques to manage errors

Question 44

What is unreachable code and how might using multiple catch blocks cause this? Provide an example.

Question 45

What are the elements that make up a try block?

Question 46

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
A block of code you attempt to execute while acknowledging that an exception might occur

Question 47

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
A language feature designed to make it harder to write bad code

Question 48

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
A process that is crucial to an organization

Question 49

What advantages does object-oriented exception handling provide?

Question 50

How is an Error class different from an Exception class?

Question 51

When a program contains multiple catch blocks, how are they handled?

Question 52

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
Constructs a new exception with the specified cause and a detail message of cause.toString()

Question 53

What is a finally block and how would a programmer use it?

Question 54

What things might a programmer do to cause a potential exception in a program?

Question 55

What are unchecked exceptions? Give an example.

Question 56

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
Applications designed so that they continue to operate when some part of the system fails

Question 57

What advantage to programmers does the technique of cycling through the methods in the stack offer? Why?

Question 58

Match each term with the correct statement below.
a.Throwable
f.Exception(Throwable cause)
b.Exception(String message)
g.fault-tolerant
c.exception handling
h.assert statement
d.syntactic salt
i.try block
e.mission critical
The parent class of Exception

Question 59

An alternative to hard coding error messages into your Exception classes is creating a catalog of possible messages to use. What are the advantages of doing so?

Question 60

What is an Exception class? Give an example.

Question 61

import java.util.Scanner;
public class AssertTest
{
public static void main( String args[] )
{
Scanner input = new Scanner( System.in );
System.out.print( "Enter a number between 0 and 10: " );
int number = input.nextInt();
assert ( number >= 0 && number <= 10 ) : "Invalid number: " + number;
System.out.printf( "You entered %d\n", number );
}
}
The above code demonstrates the functionality of the assert statement. Explain what happens when an entered number is valid and when an entered number is out of range.

Question 62

import java.util.*;
import java.util.Scanner;
public class AssertionExample
{
public static void main( String args[] )
{
Scanner scanner = new Scanner( System.in );
System.out.print( "Enter a number between 0 and 20: " );
int value = scanner.nextInt();
____
"Invalid number: " + value;
System.out.printf( "You have entered %d\n", value );
}
}
In the code above, when the user enters the number, the scanner.nextInt() method reads the number from the command line. In the blank line provided, create an assert statement that determines whether the entered number is within the valid range (between 0 and 20). If the user entered a number that is out of range, then the "Invalid number" error should occur.

Question 63

public static void main(String args[])
{
int a, b;
try
{
a = 0;
b = 42 / a;
System.out.println("This will not be printed.");
}
catch (ArithmeticException e)
{
System.out.println("Division by zero.");
}
System.out.println("After catch statement.");
}
The program above includes a try block and a catch clause that processes the ArithmeticException generated by the division-by-zero error. Explain how the try and catch blocks operate, and what the output will be following program execution.

Question 64

import java.util.*;
public class DivisionMistakeCaught3
{
public static void main(String[] args)
{
Scanner input = new Scanner(System.in);
int numerator, denominator, result;
try
{
System.out.print("Enter numerator >> ");
numerator = input.nextInt();
System.out.print("Enter denominator >> ");
denominator = input.nextInt();
result = numerator / denominator;
System.out.println(numerator + " / " + denominator + " = " + result);
}
catch(ArithmeticException mistake)
{
System.out.println(mistake.getMessage());
}
catch(InputMismatchException mistake)
{
System.out.println("Wrong data type");
}
}
}
Using the above code, describe what will happen if a user enters two usable integers. What will happen if a user enters an invalid noninteger value? What will happen if the user enters 0 for the denominator?

Question 65

public class exceptions
{
public static void main(String Args[])
{
int[] array = new int[3];
try
{
for(int a=0;a<4;++a)
{
array[a] = a;
}
System.out.println(array);
}
catch(ArrayIndexOutOfBoundsException e)
{
System.out.println("Out of bounds");
}
}
}
In the above code, the line System.out.println(array); gets skipped when an exception occurs. Write a finally block that will execute, and will execute a System.out.println(array); if there is an exception.