Given:

Which two modifications enable the code to print Open Close?
A)

B)

C)

D)

E)

1. A. Option A
2. B. Option B
3. C. Option C
4. D. Option D
5. E. Option E

Correct Answer: BE
The code given is a try-with-resources statement that declares a resource of type AutoCloseable. The resource is an anonymous class that implements the AutoCloseable interface and overrides the close() method. The code also has a print() method that prints the value of the variable s. The code is supposed to print ??Open Close??, but it does not compile because of two errors.
The first error is at line n1, where the anonymous class is missing a semicolon at the end of its declaration. This causes a syntax error and prevents the code from compiling. To fix this error, option B adds a semicolon after the closing curly brace of the anonymous class.
The second error is at line n2, where the print() method is called without an object reference. This causes a compilation error because the print() method is not static and cannot be invoked without an object. To fix this error, option E adds an object reference to the print() method by using the variable t.
Therefore, options B and E are correct and enable the code to print ??Open Close??.

Given:

What is the result?

1. A. 4
2. B. 2
3. C. 6
4. D. Nothing is printed because of an indefinite loop.
5. E. Compilation fails.
6. F. 5
7. G. A runtime exception is thrown.
8. H. 3

Correct Answer: E
The code will not compile because the variable ??x?? is declared as final and then it is being modified in the switch statement. This is not allowed in Java. A final variable is a variable whose value cannot be changed once it is initialized1. The switch statement tries to assign different values to ??x?? depending on the value of ??y??, which violates the final modifier. The compiler will report an error: The final local variable x cannot be assigned. It must be blank and not using a compound assignment. References: The final Keyword (The Java™ Tutorials > Learning the Java Language > Classes and Objects)

Given the code fragment:

1. A. True:false:true:true
2. B. True:true:false:false
3. C. True:false:true:false
4. D. True:false:false:false

Correct Answer: C
The code fragment compares four pairs of strings using the equals() and intern() methods. The equals() method compares the content of two strings, while the intern() method returns a canonical representation of a string, which means that it returns a reference to an existing string with the same content in the string pool. The string pool is a memory area where strings are stored and reused to save space and improve performance. The results of the comparisons are as follows:
✑ s1.equals(s2): This returns true because both s1 and s2 have the same content, ??Hello Java 17??.
✑ s1 == s2: This returns false because s1 and s2 are different objects with different references, even though they have the same content. The == operator compares the references of two objects, not their content.
✑ s1.intern() == s2.intern(): This returns true because both s1.intern() and s2.intern() return a reference to the same string object in the string pool, which has the content ??Hello Java 17??. The intern() method ensures that there is only one copy of each distinct string value in the string pool.
✑ ??Hello Java 17?? == s2: This returns false because ??Hello Java 17?? is a string literal, which is automatically interned and stored in the string pool, while s2 is a string object created with the new operator, which is not interned by default and stored in the heap. Therefore, they have different references and are not equal using the == operator.
References: String (Java SE 17 & JDK 17) - Oracle

Given:

What is the result?

1. A. 1 RAINY
2. B. Compilation fails
3. C. 1 Snowy
4. D. 0 CLOUDY
5. E. 0 Snowy

Correct Answer: E
The code is defining an enum class called Forecast with three values: SUNNY, CLOUDY, and RAINY. The toString() method is overridden to always return ??SNOWY??. In the main method, the ordinal value of SUNNY is printed, which is 0, followed by the value of CLOUDY converted to uppercase, which is ??CLOUDY??. However, since the
toString() method of Forecast returns ??SNOWY?? regardless of the actual value, the output
will be ??0 SNOWY??. References: Enum (Java SE 17 & JDK 17), Enum.EnumDesc (Java SE 17 & JDK 17)

Which statement is true?

1. A. IllegalStateException is thrown if a thread in waiting state is moved back to runnable.
2. B. thread in waiting state consumes CPU cycles.
3. C. A thread in waiting state must handle InterrupedException.
4. D. After the timed wait expires, the waited thread moves to the terminated state.

Correct Answer: C
A thread in waiting state is waiting for another thread to perform a particular action, such as calling notify() or notifyAll() on a shared object, or terminating a joined thread. A thread in waiting state can be interrupted by another thread, which will cause the waiting thread to throw an InterruptedException and return to the runnable state. Therefore, a thread in waiting state must handle InterruptedException, either by catching it or declaring it in the throws clause. References: Thread.State (Java SE 17 & JDK 17), [Thread (Java SE 17 & JDK 17)]