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Right option is (c) Measured Variable’s HANDLEREQUEST

The explanation: When a CLIENT makes a GET request for /voltage/actual, the request is passed to Measured Variable’s HandleRequest method. When this happens, the MeasuredVariable object FIRST calls FromSensor.

Right answer is (c) Classes

Explanation: MULTITHREADING is a mechanism for splitting up a PROGRAM into several parallel activities called threads. Multithreading MAKES it possible for TWO or more activities to execute in parallel on a single PROCESSOR.

Correct choice is (a) Null

The explanation is: This method GETS the current buffer STATE, without CHANGING it. The method performs the necessary LOCKING to enable safe of the buffer from multiple THREADS. The result may be null.

Correct answer is (b) Current BUFFER state, without changing

Explanation: This method GETS the current buffer state, without changing it. The method PERFORMS the necessary locking to ENABLE safe of the buffer from multiple threads.

The correct answer is (b) Scheduler

The explanation: MULTITHREADING on a SINGLE processor is possible with the HELP of scheduler, which briefly stops the currently execution THREAD of an application after each time SLICE.

Correct choice is (a) Null

The explanation is: void HandlePut(object o) method puts 0 into BUFFER. The new value in the buffer replaces the old one. The method PERFORMS the NECESSARY locking to enable safe use of the buffer from multi threads. Object o MAY be NULL.

The correct answer is (a) True

The EXPLANATION: FromSensor is a PROPERTY to which you can assign a method I.e., a C#delegate property. Delegate PROPERTIES must be compatible with the delegate types they represent.

Right CHOICE is (d) Both MinValue and MaxValue

To explain: Properties MinValue and MaxValue make it possible for the ANALOG SENSOR object to convert the integer input of the analog input port to a VALUE in the given range.

The CORRECT option is (a) HandlePut(OBJECT o)

The explanation: void HandlePut(object o) METHOD puts 0 into buffer. The new value in the buffer replaces the old ONE.

Correct choice is (b) 0 to 3.3

To explain: Properties MINVALUE and MAXVALUE make it POSSIBLE for the analog sensor object to convert the integer INPUT of the analog input PORT to a value in the given range, in this case it is between 0.0 to 3.3.

The correct choice is (d) Unlocking

Easiest explanation: void HandlePut(OBJECT o) method puts 0 into buffer. The new VALUE in the buffer replaces the old one. The method performs the necessary LOCKING to enable SAFE use of the buffer from multi THREADS.

Right choice is (b) 50 times per second

To elaborate: SWITCHING AMONG threads occurs so FREQUENTLY -50 times per second that all threads APPEAR to run in parallel.

Correct OPTION is (a) THREAD.Sleep

The BEST I can explain: A particular thread of the application can be BLOCKED FOREVER by calling Thread.Sleep(Timeout.Infinite).

Right choice is (C) .NET

The best I can explain: In .NET, an object of type Thread in the NAMESPACE System.Threading represents and controls ONE thread. Its constructor TAKES a parameterless method as a parameter.

Right answer is (a) False

The best explanation: Multithreading is a mechanism for SPLITTING up a program into SEVERAL parallel ACTIVITIES called threads. Each thread is a SINGLE stream of execution, yet they all share the same resources.

Correct option is (a) Multithreading

To explain I WOULD SAY: MultiThreading MAKES it possible for two or more activities to EXECUTE in parallel on a single processor.

Correct option is (b) Objects

To explain: An instance of CLASS BUFFER provides a threadsafe way of communication between actors. A buffer instance BASICALLY acts as a VARIABLE whose current VALUE can be read and written.

The correct ANSWER is (c) ROUND robin fashion

To explain: It switches among threads in a round robin fashion so that every thread GETS its FAIR share of PROCESSING time.

Correct OPTION is (d) START

The best explanation: In .NET, an OBJECT of type Thread in the namespace System.Threading represents and controls one thread. Its constructor takes a parameter LESS method as a parameter. The method will be executed once the threads Start method is called.

The correct answer is (c) VOLTAGE

For explanation: VoltageMonitor, shows how to handle GET REQUEST to a SENSOR RESOURCE, more specially one that represent some voltage.

Right choice is (a) /health

Easiest explanation: /health shows application health INFORMATION (a simple ‘status’ when accessed over an unauthenticated connection or full MESSAGE details when AUTHENTICATED). It is not SENSITIVE by default.

Right choice is (c) /METRIC

Easiest explanation: Endpoints ALLOW you to monitor the application and, in some cases, interact with it as well. /metric shows metric INFORMATION for the CURRENT application. It is also sensitive by DEFAULT.

Right option is (d) ASCII VALUES, digits, and characters

To ELABORATE: You can USE any URL as long you use ASCII letters, digits, and Characters. For example, the URL /root/sensor/analog/I would LOOK like:

http://192.168.5.100/root/sensor/analog/1.

The CORRECT OPTION is (d) Physical phenomenon

The best I can explain: A RESOURCE with measured variable will REFLECT a physical phenomenon as it currently is. The resource is updated with new sensor values from TIME to time.

Right answer is (a) True cases only

Explanation: Each ENDPOINT can be CUSTOMIZED with properties using the FOLLOWING FORMAT: endpoint.[endpoint name].[property to customize].

Enabled – if true then it can be accessed otherwise not.

The correct answer is (d) ID

Easy explanation: Each endpoint can be customized with properties USING the FOLLOWING format: endpoint.[endpoint name].[PROPERTY to customize].

Id – by which this endpoint will be accessed over HTTP.

The correct option is (a) True

Easy explanation: When the USER physically turns the potentiometer’s knob, the measured VARIABLE changes its VALUE accordingly. This means that subsequent GET request to the same resource may YIELD DIFFERENT responses.

The correct answer is (B) 3 Properties

Explanation: Each endpoint can be customized with properties using the FOLLOWING format: endpoint.[endpoint name].[property to CUSTOMIZE]. Three properties are:

1. Id

2. Enabled

3. SENSITIVE.

The correct option is (c) /METRIC

The explanation: Most endpoints are sensitive IE., MEANING they are not FULLY public. While a handful is not: /HEALTH and /metric.

Correct option is (a) Actuators

To explain: Actuators ENABLE production ready FEATURES to a SPRING boot application WITHOUT having to actually implement these things yourself.

Right answer is (c) Resources

To ELABORATE: An HTTP server manages resources. In this example, a RESOURCE is provided that has the meaning, “actual voltage value, as measured by a sensor ATTACHED to the BOARD”.

The correct CHOICE is (b) Endpoints

For explanation: Endpoints allow you to MONITOR the application and, in some cases, interact with it as well. The boot comes with many built-in endpoints and, like PRETTY MUCH anything in spring.

Right OPTION is (c) /METRIC

The best explanation: The metric endpoint is one of the most important endpoint as I gathers and publishes INFORMATION about OS, JVM and Application LEVEL metric.

Right choice is (a) DIGITAL sensor

Easiest explanation: For reading the current VOLTAGE, library class Analog Sensor that WRAPS an analog INPUT port in an object that provides the method HandleGet.

Correct option is (a) spring-BOOT-actuator

The best EXPLANATION: To start USING the EXISTING actuators in boot we will just need to add the spring-boot-actuator dependency.

Correct answer is (B) Measured variable

Best explanation: A RESOURCE that contains an actual value is called a measured variable. A measured variable changes its value over TIME, DEPENDING on a physical PROCESS.

Right option is (b) ENDPOINT

The explanation: Besides USING the EXISTING endpoint provided by SPRING boot we can create a new endpoint. We need to have endpoint implementation implement the endpoint.

Correct option is (b) /info

The best I can explain: Endpoints allow you to MONITOR the application and, in some CASES, interact with it as well. /info endpoint DISPLAYS arbitrary application INFORMATION. Not sensitive by DEFAULT.

The correct ANSWER is (d) /trace

Easy EXPLANATION: ENDPOINTS allow you to monitor the application and, in some CASES, interact with it as WELL. /trace displace trace information by default the; last few HTTP requests.

Right CHOICE is (a) HTTP

To elaborate: HelloWeb is an example of an HTTP server, but it does not USE any SENSORS or actuators.

The correct choice is (a) True

Best explanation: Health INFORMATION is COLLECTED from all the beans implementing Health INDICATOR interface CONFIGURED in your application CONTEXT.

Right answer is (d) True cases only

To explain: Each endpoint can be customized with properties using the following FORMAT: endpoint.[endpoint name].[PROPERTY to customize].

SENSITIVE – if true then NEED the authorization to show CRUCIAL information over HTTP.