Try Catch + java-visual

What is the error message in the screenshot?

• Java: unreported exception javsql.SQLException: must be caught or declared to be thrown
• Unhandled exception: java.sql.SQLException
• Errors occurred while compling module 'sad'
• javac 18.0.121 was used to compile java sources

Answer explanation

The screenshot shows a Java program that is trying to connect to a MySQL database. However, there is an error in the code that is causing the program to crash. The error message is "Java: unreported exception java.sql.SQLException: must be caught or declared to be thrown". This means that the program is not handling the SQLException exception correctly. The exception should either be caught and handled, or it should be declared so that the compiler knows about it.

What will happen if the catch block is not executed in the code snippet shown in the image?

• The program will print "Clicking on sing in Link" to the console.
• The program will throw an Exception.
• The program will continue to execute the rest of the code.
• The program will exit unexpectedly.

Answer explanation

The catch block is not mandatory in Java. If an exception is thrown in a try block and there is no catch block to handle it, the exception will simply be propagated to the calling method. In this case, the clickonSignIn() method will return without printing anything to the console. The rest of the code in the program will continue to execute as normal.

What will happen if the user enters an empty string as input in the code snippet shown in the image?

• The program will print "str1 str2" to the console.
• The program will throw an ArrayIndexOutOfBoundsException.
• The program will continue to execute the do loop.
• The program will exit unexpectedly.

Answer explanation

The ArrayIndexOutOfBoundsException exception will be thrown if the user enters an empty string as input. This is because the split() method will try to split the empty string into two parts, but there will be no parts to split. The exception will be caught by the catch block and the program will print "str1 str2" to the console.

What will be the output of the code snippet shown in the image?

• Something caught
• ArithmeticException caught
• Not quite finally
• Finally

Answer explanation

The code snippet in the image will print "Something caught" to the console. This is because the try block will throw an ArithmeticException exception when the result = 1/0 statement is executed. The ArithmeticException exception will be caught by the catch block and the program will print "Something caught" to the console. The finally block will also be executed, but it will not print anything to the console.

What is the purpose of the throw new RequestException(e) statement in the code snippet shown in the image?

• To throw a new RequestException exception.
• To catch a RequestException exception.
• To close the finally block.
• To print the stack trace of the RequestException exception.

Answer explanation

The throw new RequestException(e) statement is used to throw a new RequestException exception. This is done in the finally block because the RequestException exception may have been thrown in the try block and not caught in the catch block. By throwing the RequestException exception in the finally block, it is guaranteed that the exception will be propagated to the calling method.

What is the output of the code snippet shown in the image?

• Outer try-catch block
• java.lang.NullPointerException
• finally block always gets executed
• All of the above

Answer explanation

The code snippet in the image will print all of the options to the console. This is because the try block will throw a NullPointerException exception when the str.length() method is called on the str variable, which is null. The NullPointerException exception will be caught by the catch block and the program will print "java.lang.NullPointerException" to the console. The finally block will also be executed and it will print "finally block always gets executed" to the console.

What is the error message in the screenshot?

• Java: unreported exception javlang.ArithmeticException: divide by zero
• Unhandled exception: java.lang.ArithmeticException
• Errors occurred while compling module 'sad'
• javac 18.0.121 was used to compile java sources

Answer explanation

The screenshot shows a Java program that is trying to divide 4 by 0. This is an ArithmeticException, which is an error that occurs when a mathematical operation is performed on a number that is zero. The error message is "Java: unreported exception java.lang.ArithmeticException: divide by zero". This means that the program is not handling the ArithmeticException exception correctly. The exception should either be caught and handled, or it should be declared so that the compiler knows about it.

What is the purpose of the nested try block in the code snippet shown in the image?

• To catch the ArithmeticException exception that is thrown in the try block.
• To catch the NullPointerException exception that is thrown in the try block.
• To catch any exception that is thrown in the try block.
• To execute the code in the try block even if an exception is thrown.

Answer explanation

The nested try block is used to catch the NullPointerException exception that is thrown in the try block. The ArithmeticException exception that is thrown in the try block will be caught by the outer catch block.

What is the output of the code snippet shown in the image?

• Nothing
• ArithmeticException
• NullPointerException
• Finally

Answer explanation

The code snippet in the image will not print anything to the console. The ArithmeticException exception that is thrown in the try block will be caught by the catch block. The catch block will print the stack trace of the exception, but it will not print anything else. The finally block will also be executed, but it will not print anything to the console.

What is the purpose of the try block in the code snippet shown in the image?

• To execute code that may throw an exception.
• To execute code that will always throw an exception.
• To execute code that will only be executed if an exception is thrown.
• There is no purpose to the try block in this code snippet.

Answer explanation

The try block in the code snippet is used to execute code that may throw an exception. The check_fuel() and check_engine() methods may throw exceptions, so they are placed in the try block. If an exception is thrown by one of these methods, the catch block will be executed.