1z0-829 Questions and Answers

The code fragment is using the Java SE 17 API to get the current time and then truncating it to minutes. The result will be the current time truncated to minutes, which is why option B is correct. 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/17/docs/api/java.base/java/time/Instant.html#truncatedTo(java.time.temporal.TemporalUnit)

The answer is D because the code fragment uses the Stream API to create two streams, s1 and s2, and then concatenates them using the concat() method. The resulting stream is then processed in parallel using the parallel() method, and the distinct() method is used to remove duplicate elements. Finally, the forEach() method is used to print the elements of the resulting stream to the console. Since the order of elements in a parallel stream is unpredictable, the output could be any of the options given, but option D is the most likely. References:

• Oracle Certified Professional: Java SE 17 Developer
• Java SE 17 Developer
• OCP Oracle Certified Professional Java SE 17 Developer Study Guide
• Parallelizing Streams

The answer is D because the code fragment reads the content of the in.txt file and writes it to the out.txt file. The content of the in.txt file is “23456789”. The code fragment uses a char array buffer of size 8 to read the content of the in.txt file. The while loop reads the content of the in.txt file and writes it to the out.txt file until the end of the file is reached. Therefore, the content of the out.txt file will be “0123456789”.

The answer is B because the code fragment contains a logical error that causes a MissingResourceException at runtime. The code fragment tries to load a resource bundle with the base name “Captions.properties” and the locale “en_US”. However, there is no such resource bundle available in the classpath. The available resource bundles are:

• Captions.properties
• Captions_en.properties
• Captions_US.properties
• Captions_en_US.properties

The ResourceBundle class follows a fallback mechanism to find the best matching resource bundle for a given locale. It first tries to find the resource bundle with the exact locale, then it tries to find the resource bundle with the same language and script, then it tries to find the resource bundle with the same language, and finally it tries to find the default resource bundle with no locale. If none of these resource bundles are found, it throws a MissingResourceException.

In this case, the code fragment is looking for a resource bundle with the base name “Captions.properties” and the locale “en_US”. The ResourceBundle class will try to find the following resource bundles in order:

• Captions.properties_en_US
• Captions.properties_en
• Captions.properties

However, none of these resource bundles exist in the classpath. Therefore, the ResourceBundle class will throw a MissingResourceException.

To fix this error, the code fragment should use the correct base name of the resource bundle family, which is “Captions” without the “.properties” extension. For example:

ResourceBundle captions = ResourceBundle.getBundle(“Captions”, currentLocale);

This will load the appropriate resource bundle for the current locale, which is “Captions_en_US.properties” in this case. References:

• Oracle Certified Professional: Java SE 17 Developer
• Java SE 17 Developer
• OCP Oracle Certified Professional Java SE 17 Developer Study Guide
• ResourceBundle (Java Platform SE 8 )
• About the ResourceBundle Class (The Java™ Tutorials > Internationalization)

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

The code fragment will fail to compile because the parseInt method of the Integer class is a static method, which means that it can be invoked without creating an object of the class. However, the code is trying to invoke the parseInt method on an object of type Integer, which is not allowed. The correct way to invoke the parseInt method is by using the class name, such as Integer.parseInt (s). Therefore, the code fragment will produce a compilation error. References: Integer (Java SE 17 & JDK 17) - Oracle

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.

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.

The answer is D because the code fragment reads the file “data.txt” and collects all the lines in the file into a single string, separated by hyphens. Then, it prints the resulting string. Next, it attempts to read the fourth line in the file (index 3) and print it. However, since the file only has three lines, an IndexOutOfBoundsException is thrown. References:

• Oracle Certified Professional: Java SE 17 Developer
• Java SE 17 Developer
• OCP Oracle Certified Professional Java SE 17 Developer Study Guide
• Read contents of a file using Files class in Java

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)]