Sun.RealExamQuestions.310-065.Oracle.1Z0-851.v2012-01-28.by.Carlos.239q
Number: 1Z0-851 Passing Score: 610 Time Limit: 150 min File Version: 2012-01-28
Sun.RealExamQuestions.310-065.Oracle.1Z0-851.v2012-01-28.by.Carlos.239q
Exam : Sun 310-065 / Oracle 1Z0-851
Version : 2012-01-28
By Carlos - Brazil
Questions : 239 9 Exams (from A - I)
This file is based on Sun RealExamQuestions 310-065 v2011-11-08 by Stephen 306q.vce (http:// www.examcollection.com/sun/Sun.RealExamQuestions.310-065.v2011-11-08.by.Stephen.306q.vce. file.html). See the comments on its page for more infos.
Changes made from original file: - Removed duplicated questions. - Many answers were tested and better explained. - Removed "Exam J" because it had only drag and drop questions and other questions that had drag and drop (see posts from "Certification Forum Moderator - Brandye Barrington" on https:// forums.oracle.com/forums/thread.jspa?messageID=9640688&tstart=0#9640688)
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Exam C
QUESTION 1 A company has a business application that provides its users with many different reports: receivables reports, payables reports, revenue projects, and so on. The company has just purchased some new, state-of-the-art, wireless printers, and a programmer has been assigned the task of enhancing all of the reports to use not only the company's old printers, but the new wireless printers as well. When the programmer starts looking into the application, the programmer discovers that because of the design of the application, it is necessary to make changes to each report to support the new printers.Which two design concepts most likely explain this situation? (Choose two.)
A. Inheritance
B. Low cohesion
C. Tight coupling
D. High cohesion
E. Loose coupling
F. Object immutability
Correct Answer: BC
QUESTION 2 Given:
10. public class SuperCalc {
11. protected static int multiply(int a, int b) { return a * b;}
12. } and:
20. public class SubCalc extends SuperCalc{
21. public static int multiply(int a, int b) {
22. int c = super.multiply(a, b);
23. return c;
24. }
25. } and:
30. SubCalc sc = new SubCalc ();
31. System.out.println(sc.multiply(3,4));
32. System.out.println(SubCalc.multiply(2,2));
What is the result?
A. 12
B. The code runs with no output.
C. An exception is thrown at runtime.
D. Compilation fails because of an error in line 21.
E. Compilation fails because of an error in line 22.
F. Compilation fails because of an error in line 31.
Correct Answer: E
Explanation/Reference:
Compilation message: Cannot use super in a static context.
QUESTION 3
Given:
class Foo {
public int a = 3;
public void addFive() {
a += 5; System.out.print("f ");
}
}
class Bar extends Foo {
public int a = 8;
public void addFive() {
this.a += 5; System.out.print("b " );
}
}
Invoked with:
Foo f = new Bar();
f.addFive();
System.out.println(f.a);
What is the result?
A. b 3
B. b 8
C. b 13
D. f 3
E. f 8
F. f 13
G. Compilation fails.
H. An exception is thrown at runtime.
Correct Answer: A
QUESTION 4 A company that makes Computer Assisted Design (CAD) software has, within its application, some utility classes that are used to perform 3D rendering tasks. The company's chief scientist has just improved the performance of one of the utility classes' key rendering algorithms, and has assigned a programmer to replace the old algorithm with the new algorithm. When the programmer begins researching the utility classes, she is happy to discover that the algorithm to be replaced exists in only one class. The programmer reviews that class's API, and replaces the old algorithm with the new algorithm, being careful that her changes adhere strictly to the class's API. Once testing has begun, the programmer discovers that other classes that use the class she changed are no longer working properly. What design flaw is most likely the cause of these new bugs?
A. Inheritance
B. Tight coupling
C. Low cohesion
D. High cohesion
E. Loose coupling
F. Object immutability
Correct Answer: B
QUESTION 5 Given:
1. class ClassA { 2. public int numberOfInstances;
3. protected ClassA(int numberOfInstances) {
4. this.numberOfInstances = numberOfInstances;
5. }
6. }
7. public class ExtendedA extends ClassA {
8. private ExtendedA(int numberOfInstances) {
9. super(numberOfInstances);
10. }
11. public static void main(String[] args) {
12. ExtendedA ext = new ExtendedA(420);
13. System.out.print(ext.numberOfInstances);
14. }
15.} Which statement is true?
A. 420 is the output.
B. An exception is thrown at runtime.
C. All constructors must be declared public.
D. Constructors CANNOT use the private modifier.
E. Constructors CANNOT use the protected modifier.
Correct Answer: A
QUESTION 6 Given:
class ClassA {}
class ClassB extends ClassA {}
class ClassC extends ClassA {}
and:
ClassA p0 = new ClassA();
ClassB p1 = new ClassB();
ClassC p2 = new ClassC();
ClassA p3 = new ClassB();
ClassA p4 = new ClassC();
Which three are valid? (Choose three.)
A. p0 = p1;
B. p1 = p2;
C. p2 = p4;
D. p2 = (ClassC)p1;
E. p1 = (ClassB)p3;
F. p2 = (ClassC)p4;
Correct Answer: AEF
QUESTION 7 Given: class Thingy { Meter m = new Meter(); }
class Component { void go() { System.out.print("c"); } }
class Meter extends Component { void go() { System.out.print("m"); } }
class DeluxeThingy extends Thingy {
public static void main(String[] args) {
DeluxeThingy dt = new DeluxeThingy(); dt.m.go();
Thingy t = new DeluxeThingy(); t.m.go(); }
}
Which two are true? (Choose two.)
A. The output is mm.
B. The output is mc.
C. Component is-a Meter.
D. Component has-a Meter. E. DeluxeThingy is-a Component.
F. DeluxeThingy has-a Component.
Correct Answer: AF
QUESTION 8 Given:
10. interface Jumper { public void jump(); } ...
20. class Animal {} ...
30. class Dog extends Animal {
31. Tail tail;
32. } ...
40. class Beagle extends Dog implements Jumper{
41. public void jump() {}
42. } ...
50. class Cat implements Jumper{
51. public void jump() {}
52. }
Which three are true? (Choose three.)
A. Cat is-a Animal
B. Cat is-a Jumper
C. Dog is-a Animal
D. Dog is-a Jumper
E. Cat has-a Animal
F. Beagle has-a Tail
G. Beagle has-a Jumper
Correct Answer: BCF
QUESTION 9
Given:
1. import java.util.*;
2. public class WrappedString {
3. private String s;
4. public WrappedString(String s) { this.s = s; }
5. public static void main(String[] args) {
6. HashSet<Object> hs = new HashSet<Object>();
7. WrappedString ws1 = new WrappedString("aardvark");
8. WrappedString ws2 = new WrappedString("aardvark");
9. String s1 = new String("aardvark");
10. String s2 = new String("aardvark");
11. hs.add(ws1); hs.add(ws2); hs.add(s1); hs.add(s2);
12. System.out.println(hs.size()); } }
What is the result?
A. 0
B. 1
C.
2
D. 3
E. 4
F. Compilation fails.
G. An exception is thrown at runtime.
Correct Answer: D
The two strings are identical and they counts as only 1.
QUESTION 10 Given:
11. //insert code here
private N min, max;
public N getMin() {
return min;
}
public N getMax() {
return max;
}
public void add(N added) {
if (min == null || added.doubleValue() < min.doubleValue())
min = added;
if (max == null || added.doubleValue() > max.doubleValue())
max = added;
}
}
Which two, inserted at line 11, will allow the code to compile? (Choose two.)
A. public class MinMax<?> {
B. public class MinMax<? extends Number> {
C. public class MinMax<N extends Object> {
D. public class MinMax<N extends Number> {
E. public class MinMax<? extends Object> {
F. public class MinMax<N extends Integer> {
Correct Answer: DF
QUESTION 11 Given:
3. import java.util.*;
4. public class G1 {
5. public void takeList(List<? extends String> list) {
6. // insert code here
7. }
8. }
Which three code fragments, inserted independently at line 6, will compile? (Choose three.)
A. list.add("foo");
B. Object o = list;
C. String s = list.get(0);
D. list = new ArrayList<String>();
E. list = new ArrayList<Object>();
Correct Answer: BCD
QUESTION 12 Given that the elements of a PriorityQueue are ordered according to natural ordering, and:
import java.util.*;
public class GetInLine {
public static void main(String[] args) {
PriorityQueue<String> pq = new PriorityQueue<String>();
pq.add("banana");
pq.add("pear");
pq.add("apple");
System.out.println(pq.poll() + " " + pq.peek());
}
}
What is the result?
A. apple pear
B. banana pear
C. apple apple
D. apple banana
E. banana banana
Correct Answer: D
QUESTION 13 Given:
enum Example { ONE, TWO, THREE }
Which statement is true?
A. The expressions (ONE == ONE) and ONE.equals(ONE) are both guaranteed to be true.
B. The expression (ONE < TWO) is guaranteed to be true and ONE.compareTo(TWO) is guaranteed to be
less than one.
C. The Example values cannot be used in a raw java.util.HashMap; instead, the programmer must use a
java.util.EnumMap.
D. The Example values can be used in a java.util.SortedSet, but the set will NOT be sorted because
enumerated types do NOT implement java.lang.Comparable.
Correct Answer: A
QUESTION 14 Given:
import java.util.*;
public class Mapit {
public static void main(String[] args) {
Set<Integer> set = new HashSet<Integer>();
Integer i1 = 45;
Integer i2 = 46;
set.add(i1);
set.add(i1);
set.add(i2);
System.out.print(set.size() + " ");
set.remove(i1);
System.out.print(set.size() + " "); i2 = 47;
set.remove(i2);
System.out.print(set.size() + " ");
}
}
What is the result?
A. 2 1 0
B. 2 1 1
C. 3 2 1
D. 3 2 2
E. Compilation fails.
F. An exception is thrown at runtime.
Correct Answer: B
QUESTION 15
Given:
import java.util.*;
public class Explorer1 {
public static void main(String[] args) {
TreeSet<Integer> s = new TreeSet<Integer>();
TreeSet<Integer> subs = new TreeSet<Integer>();
for(int i = 606; i < 613; i++)
if(i%2 == 0)
s.add(i);
subs = (TreeSet)
s.subSet(608, true, 611, true);
s.add(609);
System.out.println(s + " " + subs);
}
}
What is the result?
A. Compilation fails.
B. An exception is thrown at runtime.
C. [608, 609, 610, 612] [608, 610]
D. [608, 609, 610, 612] [608, 609, 610]
E. [606, 608, 609, 610, 612] [608, 610]
F. [606, 608, 609, 610, 612] [608, 609, 610]
Correct Answer: F
QUESTION 16 Given:
import java.util.*;
public class Quest {
public static void main(String[] args) {
String[] colors = {"blue", "red", "green", "yellow", "orange"}; Arrays.sort(colors);
int s2 = Arrays.binarySearch(colors, "orange");
int s3 = Arrays.binarySearch(colors, "violet");
System.out.println(s2 + " " + s3);
}
}
What is the result?
A. 2 -1
B. 2 -4
C. 2 -5
D. 3 -1
E. 3 -4
F. 3 -5
G. Compilation fails.
H. An exception is thrown at runtime.
Correct Answer: C
Explanation/Reference:
Next item index: (-(number of itens)-1)
QUESTION 17 Given:
HashMap props = new HashMap();
props.put("key45", "some value");
props.put("key12", "some other value"); props.put("key39", "yet another value");
Set s = props.keySet();
//insert code here What, inserted at line 39, will sort the keys in the props HashMap?
A. Arrays.sort(s);
B. s = new TreeSet(s);
C. Collections.sort(s);
D. s = new SortedSet(s);
Correct Answer: B
QUESTION 18 Which two statements are true? (Choose two.)
A. It is possible to synchronize static methods.
B. When a thread has yielded as a result of yield(), it releases its locks.
C. When a thread is sleeping as a result of sleep(), it releases its locks.
D. The Object.wait() method can be invoked only from a synchronized context.
E. The Thread.sleep() method can be invoked only from a synchronized context.
F. When the thread scheduler receives a notify() request, and notifies a thread, that thread immediately
releases its lock.
Correct Answer: AD
QUESTION 19 Given:
public class TestOne implements Runnable {
public static void main (String[] args) throws Exception {
Thread t = new Thread(new TestOne()); t.start();
System.out.print("Started");
t.join();
System.out.print("Complete");
}
public void run() {
for (int i = 0; i < 4; i++) {
System.out.print(i);
}
}
}
What can be a result?
A. Compilation fails.
B. An exception is thrown at runtime.
C. The code executes and prints "StartedComplete".
D. The code executes and prints "StartedComplete0123".
E. The code executes and prints "Started0123Complete".
Correct Answer: E
QUESTION 20 Which three will compile and run without exception? (Choose three.)
A. private synchronized Object o;
B. void go() {
synchronized() { /* code here */ }
C. public synchronized void go() { /* code here */ }
D. private synchronized(this) void go() { /* code here */ }
E. void go() {
synchronized(Object.class) { /* code here */ }
F. void go() {
Object o = new Object(); synchronized(o) { /* code here */ }
Correct Answer: CEF
QUESTION 21 Given:
1. public class TestFive {
2. private int x;
3. public void foo() {
4. int current = x;
5. x = current + 1;
6. }
7. public void go() {
8. for(int i = 0; i < 5; i++) {
9. new Thread() {
10. public void run() { 11. foo(); 12. System.out.print(x + ", ");
13. } }.start();
14. } }
15.}
Which two changes, taken together, would guarantee the output: 1, 2, 3, 4, 5, ? (Choose two.)
A. move the line 12 print statement into the foo() method
B. change line 7 to public synchronized void go() {
C. change the variable declaration on line 2 to private volatile int x;
D. wrap the code inside the foo() method with a synchronized( this ) block
E. wrap the for loop code inside the go() method with a synchronized block synchronized(this) { // for loop
code here }
Correct Answer: AD
QUESTION 22 Given that t1 is a reference to a live thread, which is true?
A. The Thread.sleep() method can take t1 as an argument.
B. The Object.notify() method can take t1 as an argument.
C. The Thread.yield() method can take t1 as an argument.
D. The Thread.setPriority() method can take t1 as an argument.
E. The Object.notify() method arbitrarily chooses which thread to notify.
Correct Answer: E
QUESTION 23 Given:
Runnable r = new Runnable() {
public void run() {
System.out.print("Cat");
}
};
Thread t = new Thread(r) {
public void run() {
System.out.print("Dog");
}
};
t.start();
What is the result?
A. Cat
B. Dog
C. Compilation fails.
D. The code runs with no output.
E. An exception is thrown at runtime.
Correct Answer: B
QUESTION 24 Given:
1. public class Threads5 {
2. public static void main (String[] args) {
3. new Thread(new Runnable() {
4. public void run() {
5. System.out.print("bar");
6. }}).start();
7. }
8. } What is the result?
A. Compilation fails.
B. An exception is thrown at runtime.
C. The code executes normally and prints "bar".
D. The code executes normally, but nothing prints.
Correct Answer: C
QUESTION 25 Given:
class One {
void foo() { }
}
class Two extends One {
14. // insert method here }
Which three methods, inserted individually at line 14, will correctly complete class Two? (Choose three.)
A. int foo() { /* more code here */ }
B. void foo() { /* more code here */ }
C. public void foo() { /* more code here */ }
D. private void foo() { /* more code here */ }
E. protected void foo() { /* more code here */ }
Correct Answer: BCE
QUESTION 26 Given:
abstract public class Employee {
protected abstract double getSalesAmount();
public double getCommision() {
return getSalesAmount() * 0.15;
}
}
class Sales extends Employee {
17. // insert method here }
Which two methods, inserted independently at line 17, correctly complete the Sales class? (Choose two.)
A. double getSalesAmount() { return 1230.45; }
B. public double getSalesAmount() { return 1230.45; }
C. private double getSalesAmount() { return 1230.45; }
D. protected double getSalesAmount() { return 1230.45; }
Correct Answer: BD
QUESTION 27 Given:
1. class X {
2. X() { System.out.print(1); }
3. X(int x) {
4. this(); System.out.print(2);
5. }
6. }
7. public class Y extends X {
8. Y() { super(6); System.out.print(3); }
9. Y(int y) {
10. this(); System.out.println(4);
11. }
12. public static void main(String[] a) { new Y(5); }
13.}
What is the result?
A. 13
B. 134
C. 1234
D. 2134
E. 2143
F. 4321
Correct Answer: C
QUESTION 28 Given:
package com.sun.scjp;
public class Geodetics {
public static final double DIAMETER = 12756.32; // kilometers } Which two correctly access the DIAMETER member of the Geodetics class? (Choose two.)
A. import com.sun.scjp.Geodetics;
public class TerraCarta {
public double halfway() { return Geodetics.DIAMETER/2.0; }
B. import static com.sun.scjp.Geodetics;
public class TerraCarta{ public double halfway() { return DIAMETER/2.0; } }
C. import static com.sun.scjp.Geodetics.*;
public class TerraCarta {
public double halfway() { return DIAMETER/2.0; } }
D. package com.sun.scjp;
public class TerraCarta {
public double halfway() { return DIAMETER/2.0; } }
Correct Answer: AC
QUESTION 29 Given:
1. public class A {
2. public void doit() {
3. }
4. public String doit() {
5. return "a";
6. }
7. public double doit(int x) {
8. return 1.0;
9. }
10.} What is the result?
A. An exception is thrown at runtime.
B. Compilation fails because of an error in line 7.
C. Compilation fails because of an error in line 4.
D. Compilation succeeds and no runtime errors with class A occur.
Correct Answer: C
QUESTION 30 Given:
35. String #name = "Jane Doe";
36. int $age = 24;
37. Double _height = 123.5;
38. double ~temp = 37.5;
Which two statements are true? (Choose two.)
A. Line 35 will not compile.
B. Line 36 will not compile.
C. Line 37 will not compile.
D. Line 38 will not compile.
Correct Answer: AD
QUESTION 31 Click the Exhibit button. Given the fully-qualified class names:
com.bar.blatz.Sun
Which graph represents the correct directory structure for a JAR file from which those classes can be used by the compiler and JVM?
com.foo.bar.Dog
com.foo.bar.blatz.Book
com.bar.Car
A. Jar A
B. Jar B
C. Jar C
D. Jar D
E. Jar E
Correct Answer: A
QUESTION 32 Click the Exhibit button. Given:
ClassA a = new ClassA();
a.methodA();
What is the result?
A. Compilation fails.
B. ClassC is displayed.
C. The code runs with no output.
D. An exception is thrown at runtime.
Correct Answer: D
Explanation
The classC object is not instantiated.
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