SCJP刷题学习笔记（Part seven）

QUESTION 61

Given:

	public interface Moveable {
		public default void walk (Integer distance) {System.out.println
		("Walking");}
		public void run(Integer distance);
		}

Which statement is true?

A.
Moveable
can be used as below:

Moveable animal = n - > System.out.println(“Running” + n);

animal.run(100);

animal.walk(20);

B.
Moveable
can be used as below:

Moveable animal = n - > n + 10;

animal.run(100);

animal.walk(20);

C.
Moveable
can be used as below:

Moveable animal = (Integer n) - > System.out.println(n);

animal.run(100);

Moveable.walk(20);

D.
Movable
cannot be used in a lambda expression.

Correct Answer:
A

Section: (none)

Explanation

Explanation/Reference:

QUESTION 62

Which two code blocks correctly initialize a Locale variable? (Choose two.)

A.
Locale loc1 = "UK";

B.
Locale loc2 = Locale.getInstance("ru");

C.
Locale loc3 = Locale.getLocaleFactory("RU");

D.
Locale loc4 = Locale.UK;

E.
Locale loc5 = new Locale ("ru", "RU");

Correct Answer:
DE

Section: (none)

Explanation

Explanation/Reference:

QUESTION 63

Given:

class FuelNotAvailException extends Exception { }
class Vehicle {
void ride() throws FuelNotAvailException { //line n1
System.out.println(“Happy Journey!”);
}
}
class SolarVehicle extends Vehicle {
public void ride () throws Exception { //line n2
super.ride ();
}
}

and the code fragment:

public static void main (String[] args) throws FuelNotAvailException, Exception
{
Vehicle v = new SolarVehicle ();
v.ride();
}

Which modification enables the code fragment to print
Happy Journey!
?

A. Replace
line n1
with
public void ride() throws FuelNotAvailException {

B. Replace
line n1
with
protected void ride() throws Exception {

C. Replace
line n2
with
void ride() throws Exception {

D. Replace
line n2
with
private void ride() throws FuelNotAvailException {

Correct Answer:
B

Section: (none)

Explanation

Explanation/Reference:

抛出异常、自定义异常：
https://blog.csdn.net/qq_18505715/article/details/73196421

QUESTION 64

Given the definition of the
Emp
class:

public class Emp
{
private String eName;
private Integer eAge;

Emp(String eN, Integer eA) {
this.eName = eN;
this.eAge = eA;
}
public Integer getEAge () {return eAge;}
public String getEName () {return eName;}
}

and code fragment:

Listli = Arrays.asList(new Emp("Sam", 20), new Emp("John", 60), new Emp
				("Jim", 51));
				Predicate agVal = s -> s.getEAge() > 50; //line n1
				li = li.stream().filter(agVal).collect(Collectors.toList());
				Stream names = li.stream().map(Emp::getEName); //line n2
				names.forEach(n -> System.out.print(n + " " ));

What is the result?

A.
Sam John Jim

B.
John Jim

C. A compilation error occurs at
line n1
.

D. A compilation error occurs at
line n2
.

Correct Answer:
B

Section: (none)

Explanation

Explanation/Reference:

Part three 涉及到的Predicate函数：
https://blog.csdn.net/qq_27416233/article/details/83418791

Part one 涉及到的
Arrays.asList说明:
https://blog.csdn.net/chenleixing/article/details/43775127

Part two 涉及到的Stream语法：https://blog.csdn.net/SeanTandol/article/details/86630437

QUESTION 65

For which three objects must a vendor provide implementations in its JDBC driver? (Choose three.)

A.
Time

B.
Date

C.
Statement

D.
ResultSet

E.
Connection

F.
SQLException

G.
DriverManager

Correct Answer:
CDE

Section: (none)

Explanation

Explanation/Reference:

Explanation:

Database vendors support JDBC through the JDBC driver interface or through the ODBC connection. Each

driver must provide implementations of java.sql.Connection, java.sql.Statement,

java.sql.PreparedStatement, java.sql.CallableStatement, and java.sql.Re sultSet. They must also

implement the java.sql.Driver interface for use by the generic java.sql.DriverManager interface.

QUESTION 66

Given the code fragment:

LocalDate valentinesDay =LocalDate.of(2015, Month.FEBRUARY, 14);
LocalDate nextYear = valentinesDay.plusYears(1);
nextYear.plusDays(15); //line n1
System.out.println(nextYear);

What is the result?

A. 2016-02-14

B. A
DateTimeException
is thrown.

C. 2016-02-29

D. A compilation error occurs at
line n1
.

Correct Answer:
A

Section: (none)

Explanation

Explanation/Reference:

LocalDate的使用：
https://blog.csdn.net/u011055819/article/details/80070429

QUESTION 67

Given the code fragment:

BiFunction val = (t1, t2) -> t1 + t2; //line n1
System.out.println(val.apply(10, 10.5));

What is the result?

A. 20

B. 20.5

C. A compilation error occurs at
line n1
.

D. A compilation error occurs at
line n2
.

Correct Answer:
C

Section: (none)

Explanation

error：Type mismatch: cannot convert from double to Integer

Explanation/Reference:

BiFunction说明：
https://blog.csdn.net/u014331288/article/details/76319219

QUESTION 68

Which statement is true about
java.time.Duration
?

A. It tracks time zones.

B. It preserves daylight saving time.

C. It defines time-based values.

D. It defines date-based values.

Correct Answer:
C

Section: (none)

Explanation

Explanation/Reference:

Reference:
http://tutorials.jenkov.com/java-date-time/duration.html#accessing-the-time-of-a-duration

QUESTION 69

Given the code fragment:

UnaryOperator uo1 = s -> s*2; line n1
List loanValues = Arrays.asList(1000.0, 2000.0);
loanValues.stream()
.filter(lv -> lv >= 1500)
.map(lv -> uo1.apply(lv))
.forEach(s -> System.out.print(s + “ “));

What is the result?

A. 4000.0

B. 4000

C. A compilation error occurs at
line n1
.

D. A compilation error occurs at
line n2
.

Correct Answer:
D

Section: (none)

Explanation

error：Multiple markers at this line
- Cannot infer type argument(s) for map(Function)
- Line breakpoint:Test1 [line: 28] - main(String[])

Explanation/Reference:

QUESTION 70

You have been asked to create a ResourceBundle which uses a properties file to localize an application.