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NEW QUESTION # 17
Given the code fragment:
What is the result?
- A. 0110
- B. 010 optional (Newyear)
- C. False true true optional (Newyear)
- D. True true false NewYear
Answer: C
Explanation:
The code fragment is using the stream methods allMatch, anyMatch, noneMatch, and findFirst on a list of strings called specialDays. These methods are used to perform matching operations on the elements of a stream, such as checking if all, any, or none of the elements satisfy a given predicate, or finding the first element that matches a predicate1. The predicate in this case is that the string equals "Labour" or "Halloween". The output will be:
False: because not all of the elements in specialDays are equal to "Labour" or "Halloween".
true: because at least one of the elements in specialDays is equal to "Labour" or "Halloween".
true: because none of the elements in specialDays are equal to both "Labour" and "Halloween".
Optional[NewYear]: because the first element in specialDays that matches the predicate is "NewYear", and the findFirst method returns an Optional object that may or may not contain a non-null value2.
NEW QUESTION # 18
Given the code fragment:
- A. True:false:true:false
- B. True:false:false:false
- C. True:false:true:true
- D. True:true:false:false
Answer: A
Explanation:
Explanation
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
NEW QUESTION # 19
Given the code fragment:
What is the result?
- A. 0110
- B. 010 optional (Newyear)
- C. False true true optional (Newyear)
- D. True true false NewYear
Answer: C
Explanation:
Explanation
The code fragment is using the stream methods allMatch, anyMatch, noneMatch, and findFirst on a list of strings called specialDays. These methods are used to perform matching operations on the elements of a stream, such as checking if all, any, or none of the elements satisfy a given predicate, or finding the first element that matches a predicate1. The predicate in this case is that the string equals "Labour" or
"Halloween". The output will be:
False: because not all of the elements in specialDays are equal to "Labour" or "Halloween".
true: because at least one of the elements in specialDays is equal to "Labour" or "Halloween".
true: because none of the elements in specialDays are equal to both "Labour" and "Halloween".
Optional[NewYear]: because the first element in specialDays that matches the predicate is "NewYear", and the findFirst method returns an Optional object that may or may not contain a non-null value2.
References: Stream (Java SE 17 & JDK 17), Optional (Java SE 17 & JDK 17)
NEW QUESTION # 20
Given:
Which statement is true while the program prints GC?
- A. None of the objects are eligible for garbage collection.
- B. Only the object referenced by t2 is eligible for garbage collection.
- C. Both the objects previously referenced by t1 are eligible for garbage collection.
- D. Only one of the objects previously referenced by t1 is eligible for garbage collection.
Answer: C
NEW QUESTION # 21
Which statement is true?
- A. The lock () method returns a boolean indicator immediately if it has managed to acquire the lock, otherwise it waits for the lock acquisition.
- B. The tryLock () method returns a boolean indicator immediately if it has managed to acquire the lock, otherwise it waits for the lock acquisition.
- C. The tryLock () method returns a boolean indicator immediately regardless if it has or has not managed to acquire the lock.
- D. The Lock () method returns a boolean indicator immediately regardless if it has or has not managed to acquire the lock
Answer: C
Explanation:
The tryLock () method of the Lock interface is a non-blocking attempt to acquire a lock. It returns true if the lock is available and acquired by the current thread, and false otherwise. It does not wait for the lock to be released by another thread. This is different from the lock () method, which blocks the current thread until the lock is acquired, and does not return any value. Reference: https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/concurrent/locks/Lock.html#tryLock(), 3, 4, 5
NEW QUESTION # 22
Which statement is true?
- A. thread in waiting state consumes CPU cycles.
- B. IllegalStateException is thrown if a thread in waiting state is moved back to runnable.
- C. A thread in waiting state must handle InterrupedException.
- D. After the timed wait expires, the waited thread moves to the terminated state.
Answer: C
Explanation:
Explanation
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)]
NEW QUESTION # 23
Assume you have an automatic module from the module path display-ascii-0.2. jar. Which name is given to the automatic module based on the given JAR file?
- A. Display-ascii-0.2
- B. Display.ascii
- C. Display-ascii-0
- D. Display-ascii
Answer: D
Explanation:
Explanation
An automatic module name is derived from the name of the JAR file when it does not contain a module-info.class file. If the JAR file has an "Automatic-Module-Name" attribute in its main manifest, then its value is the module name. Otherwise, the module name is derived from the JAR file's name by removing any version numbers and converting it to lower case. Therefore, for a JAR named display-ascii-0.2.jar, the automatic module name would be display-ascii, following these rules.
NEW QUESTION # 24
Given:
What is the result?
- A. flipsflips
- B. flipsruns
- C. Compilation fails
- D. runsruns
- E. runsflips
Answer: C
Explanation:
The code fragment will fail to compile because the play method in the Dog class is declared as private, which means that it cannot be accessed from outside the class. The main method is trying to call the play method on a Dog object, which is not allowed. Therefore, the code fragment will produce a compilation error.
NEW QUESTION # 25
Given:
What is the result?
- A. Mb
- B. MA
- C. mA
- D. Mb
MC - E. Mb
Answer: C
Explanation:
Explanation
The code snippet is an example of Java SE 17 code. The code is checking if the object is an instance of class C and if it is, it will print "mC". If it is not an instance of class C, it will print "mA". In this case, the object is not an instance of class C, so the output will be "mA". References: Pattern Matching for instanceof - Oracle Help Center
NEW QUESTION # 26
Given the directory structure:
Given the definition of the Doc class:
Which two are valid definition of the wordDoc class?
- A. Package p1, p2;
Public non-sealed class WordDoc extends Doc () - B. Package p1,
non-sealed abstract class WordDoc extends Doc () - C. Package p1;
Public non-sealed class wordDoc extends Doc () - D. Package p1;
Public final class WordDoc extends Doc () - E. Package p1, p2;
Public sealed class WordDoc extends Doc () - F. Package p1;
Public class wordDoc extends Doc ()
Answer: C,D
Explanation:
The correct answer is A and F because the wordDoc class must be a non-sealed class or a final class to extend the sealed Doc class. Option B is incorrect because the wordDoc class must be non-sealed or final. Option C is incorrect because the wordDoc class cannot be in a different package than the Doc class. Option D is incorrect because the wordDoc class cannot be a sealed class. Option E is incorrect because the wordDoc class cannot be an abstract class. Reference: Oracle Certified Professional: Java SE 17 Developer, 3 Sealed Classes - Oracle Help Center
NEW QUESTION # 27
Daylight Saving Time (DST) is the practice of advancing clocks at the start of spring by one hour and adjusting them backward by one hour in autumn.
Considering that in 2021, DST in Chicago (Illinois) ended on November 7th at 2 AM, and given the fragment:
What is the output?
- A. true
false - B. false
true - C. true
true - D. False
false
Answer: A
Explanation:
The answer is A because the code fragment uses the ZoneId and ZonedDateTime classes to create two date-time objects with the same local date-time but different zone offsets. The ZoneId class represents a time-zone ID, such as America/Chicago, and the ZonedDateTime class represents a date-time with a time-zone in the ISO-8601 calendar system. The code fragment creates two ZonedDateTime objects with the same local date-time of 2021-11-07T01:30, but different zone IDs of America/Chicago and UTC. The code fragment then compares the two objects using the equals and isEqual methods.
The equals method compares the state of two objects for equality. In this case, it compares the local date-time, zone offset, and zone ID of the two ZonedDateTime objects. Since the zone offsets and zone IDs are different, the equals method returns false.
The isEqual method compares the instant of two temporal objects for equality. In this case, it compares the instant of the two ZonedDateTime objects, which is derived from the local date-time and zone offset. Since DST in Chicago ended on November 7th at 2 AM in 2021, the local date-time of 2021-11-07T01:30 in America/Chicago corresponds to the same instant as 2021-11-07T06:30 in UTC. Therefore, the isEqual method returns true.
Hence, the output is true false. Reference:
Oracle Certified Professional: Java SE 17 Developer
Java SE 17 Developer
OCP Oracle Certified Professional Java SE 17 Developer Study Guide
ZoneId (Java Platform SE 8 )
ZonedDateTime (Java Platform SE 8 )
Time Zone & Clock Changes in Chicago, Illinois, USA
Daylight Saving Time Changes 2023 in Chicago, USA
NEW QUESTION # 28
Given:
What is the result?
- A. Software Game Chess 2
- B. Software Game Chess 0
- C. Software Game read error
- D. Software game write error
- E. Software Game Software Game chess 0
- F. Software Game Software Game Chese 2
Answer: F
Explanation:
Explanation
The answer is B because the code uses the writeObject and readObject methods of the ObjectOutputStream and ObjectInputStream classes to serialize and deserialize the Game object. These methods use the default serialization mechanism, which writes and reads the state of the object's fields, including the inherited ones. Therefore, the title field of the Software class is also serialized and deserialized along with the players field of the Game class. The toString method of the Game class calls the toString method of the Software class using super.toString(), which returns the value of the title field.
Hence, when the deserialized object is printed, it shows "Software Game Software Game Chess 2".
References:
Oracle Certified Professional: Java SE 17 Developer
Java SE 17 Developer
OCP Oracle Certified Professional Java SE 17 Developer Study Guide
Serialization and Deserialization in Java with Example
NEW QUESTION # 29
Given:
What is the result?
- A. 100
100
1000 - B. 101
101
1000 - C. 1001
1001
1000 - D. 1001
100
1000
Answer: D
Explanation:
Explanation
The code fragment is using the bitwise operators & (AND), | (OR), and ^ (XOR) to perform operations on the binary representations of the integer values. The & operator returns a 1 in each bit position where both operands have a 1, the | operator returns a 1 in each bit position where either operand has a 1, and the ^ operator returns a 1 in each bit position where only one operand has a 1. The binary representations of the integer values are as follows:
1000 = 1111101000
100 = 1100100
101 = 1100101
The code fragment performs the following operations:
x = x ^ y; // x becomes 1111010101, which is 1001 in decimal
y = x ^ y; // y becomes 1100100, which is 100 in decimal
x = x ^ y; // x becomes 1100101, which is 101 in decimal
The code fragment then prints out the values of x, y, and z, which are 1001, 100, and 1000 respectively.
Therefore, option D is correct.
NEW QUESTION # 30
Given the code fragment:
Which action enables the code to compile?
- A. Replace thye regNo variable static
- B. Remove the regNO initialization statement.
- C. Make the regNo variable public
- D. Replace record with void.
- E. Make the regNo variable static.
Answer: C
Explanation:
Explanation
The code will compile if the regNo variable is made public. This is because the regNo variable is being accessed in the main method of the App class, which is outside the scope of the Product class. Making the regNo variable public will allow it to be accessed from outside the class. References:
https://education.oracle.com/products/trackp_OCPJSE17,
https://mylearn.oracle.com/ou/learning-path/java-se-17-developer/99487,
https://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html
NEW QUESTION # 31
Which statement is true about modules?
- A. Automatic and unnamed modules are on the module path.
- B. Automatic and named modules are on the module path.
- C. Only named modules are on the module path.
- D. Only unnamed modules are on the module path.
- E. Only automatic modules are on the module path.
Answer: B
Explanation:
Explanation
A module path is a sequence of directories that contain modules or JAR files. A named module is a module that has a name and a module descriptor (module-info.class) that declares its dependencies and exports. An automatic module is a module that does not have a module descriptor, but is derived from the name and contents of a JAR file. Both named and automatic modules can be placed on the module path, and they can be resolved by the Java runtime. An unnamed module is a special module that contains all the classes that are not in any other module, such as those on the class path. An unnamed module is not on the module path, but it can read all other modules.
NEW QUESTION # 32
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