Question 1

Consider the examples below:
a)a string.
b)'a string'.
c)"a string".
d)"1234".
e)integer.
Which could be the value of a Java variable of type String?

Accepted Answer

A) A and B. 
B) B and E. 
C) B and C. 
D) C and D. 
A) A and B. 
B) B and E. 
C) B and C. 
D) C and D. D

Question 2

StringBuilder objects can be used in place of String objects if ________.

Accepted Answer

A) the string data is not constant 
B) the string data size may grow 
C) the programs frequently perform string concatenation 
D) All of the above. 
A) the string data is not constant 
B) the string data size may grow 
C) the programs frequently perform string concatenation 
D) All of the above. D

Question 3

To find the character at a certain index position within a String,use the method ________.

Accepted Answer

A) getChars,with the index as an argument 
B) getCharAt,with the index as an argument 
C) charAt,with the index as an argument 
D) charAt,with the character you are searching for as an argument 
A) getChars,with the index as an argument 
B) getCharAt,with the index as an argument 
C) charAt,with the index as an argument 
D) charAt,with the character you are searching for as an argument C

Question 4

Which of the following creates the string of the numbers from 1 to 1000 most efficiently?

Accepted Answer

A) String s;
For (int i = 1;i <= 1000;i++)
S += i; 
B) StringBuilder sb = new StringBuilder(10);
For (int i = 1;i <= 1000;i++)
Sb)append(i);
String s = new String(sb); 
C) StringBuilder sb = new StringBuilder(3000);
For (int i = 1;i <= 1000;i++)
Sb)append(i);
String s = new String(sb); 
D) All are equivalently efficient. 
A) String s;
For (int i = 1;i <= 1000;i++)
S += i; 
B) StringBuilder sb = new StringBuilder(10);
For (int i = 1;i <= 1000;i++)
Sb)append(i);
String s = new String(sb); 
C) StringBuilder sb = new StringBuilder(3000);
For (int i = 1;i <= 1000;i++)
Sb)append(i);
String s = new String(sb); 
D) All are equivalently efficient.

Question 5

The length of a string can be determined by ________.

Accepted Answer

A) the String method length() 
B) the String instance variable length 
C) the String method strlen() 
D) All of the above. 
A) the String method length() 
B) the String instance variable length 
C) the String method strlen() 
D) All of the above.

Question 6

Consider the Java segment:
String line1 = new String("c = 1 + 2 + 3");
StringTokenizer tok = new StringTokenizer(line1,"+=");
String foo = tok.nextToken();
String bar = tok.nextToken();
The values of foo and bar are:

Accepted Answer

A) foo is "c ",bar is " = ". 
B) foo is "c",bar is " ". 
C) foo is " = ",bar is " + ". 
D) foo is "c ",bar is " 1 ". 
A) foo is "c ",bar is " = ". 
B) foo is "c",bar is " ". 
C) foo is " = ",bar is " + ". 
D) foo is "c ",bar is " 1 ".

Question 7

Which of the following statements is true?

Accepted Answer

A) Ranges of characters can be represented by placing a ~ between two characters. 
B) [^Z] is the same as [A~Y]. 
C) Both "A*" and "A+" will match "AAA",but only "A*" will match an empty string. 
D) All of above. 
A) Ranges of characters can be represented by placing a ~ between two characters. 
B) [^Z] is the same as [A~Y]. 
C) Both "A*" and "A+" will match "AAA",but only "A*" will match an empty string. 
D) All of above.

Question 8

Given the following declaration:
StringBuilder buf = new StringBuilder();
What is the capacity of buf?

Accepted Answer

A) 0 
B) 10 
C) 16 
D) 20 
A) 0 
B) 10 
C) 16 
D) 20

Question 9

Which class is not a type-wrapper class?

Accepted Answer

A) Character 
B) Int 
C) Double 
D) Byte 
A) Character 
B) Int 
C) Double 
D) Byte

Question 10

Consider the statement below:
StringBuilder sb1 = new StringBuilder("a toyota");
Which of the following creates a String object with the value "toy"?

Accepted Answer

A) String res = sb1.subString(2,5); 
B) char dest[] = new char[sb1.length()];
Sb1)getChars(2,5,dest,0);
String res = new String(dest); 
C) char dest[] = new char[sb1.length];
Dest = sb1.getChars(2,5);
String res = new String(dest); 
D) char dest[] = new char[sb1.length()];
Dest = sb1.getChars(0,3);
String res = new String(dest); 
A) String res = sb1.subString(2,5); 
B) char dest[] = new char[sb1.length()];
Sb1)getChars(2,5,dest,0);
String res = new String(dest); 
C) char dest[] = new char[sb1.length];
Dest = sb1.getChars(2,5);
String res = new String(dest); 
D) char dest[] = new char[sb1.length()];
Dest = sb1.getChars(0,3);
String res = new String(dest);

Question 11

Which of the following are static Character methods?

Accepted Answer

A) Character.hashcode(char c); 
B) Character.isDigit(char c); 
C) Character.equals(char c); 
D) All of the above. 
A) Character.hashcode(char c); 
B) Character.isDigit(char c); 
C) Character.equals(char c); 
D) All of the above.

Question 12

Consider the Java segment:
String line1 = new String("c = 1 + 2 + 3");
StringTokenizer tok = new StringTokenizer(line1);
Int count = tok.countTokens();
The value of count is ________.

Accepted Answer

A) 8. 
B) 7. 
C) 13. 
D) 4. 
A) 8. 
B) 7. 
C) 13. 
D) 4.

Question 13

Consider the Java segment:
String line1 = new String("c = 1 + 2 + 3");
StringTokenizer tok = new StringTokenizer(line1,delimArg);
For the String line1 to have 4 tokens,delimArg should be:

Accepted Answer

A) String delimArg = "+="; 
B) String delimArg = "123" 
C) String delimArg = "c+"; 
D) String delimArg = " "; 
A) String delimArg = "+="; 
B) String delimArg = "123" 
C) String delimArg = "c+"; 
D) String delimArg = " ";

Question 14

The String method substring returns ________.

Accepted Answer

A) a char 
B) a String 
C) void 
D) a char[] 
A) a char 
B) a String 
C) void 
D) a char[]

Question 15

How many String objects are instantiated by the following code segment (not including the literals)?
String s1,output;
S1 = "hello";
Output = "
The string reversed is: " ;
For (int i = s1.length()- 1;i >= 0;i--)
Output += s1.charAt(i)+ " " ;

Accepted Answer

A) 1. 
B) 4. 
C) 5. 
D) 7. 
A) 1. 
B) 4. 
C) 5. 
D) 7.

Question 16

Which of the following will create a String different from the other three?

Accepted Answer

A) String r = "123456" 
B) int i = 123;
Int j = 456;
String r = String.valueOf(j)+ String.valueOf(i); 
C) int i = 123;
Int j = 456;
String r = String.valueOf(i)+ String.valueOf(j); 
D) int i = 123;
Int j = 456;
String r = i + j; 
A) String r = "123456" 
B) int i = 123;
Int j = 456;
String r = String.valueOf(j)+ String.valueOf(i); 
C) int i = 123;
Int j = 456;
String r = String.valueOf(i)+ String.valueOf(j); 
D) int i = 123;
Int j = 456;
String r = i + j;

Question 17

Which of the following statements is true?

Accepted Answer

A) The capacity of a StringBuilder is equal to its length. 
B) The capacity of a StringBuilder cannot exceed its length. 
C) The length of a StringBuilder cannot exceed its capacity. 
D) Both a and b are true. 
A) The capacity of a StringBuilder is equal to its length. 
B) The capacity of a StringBuilder cannot exceed its length. 
C) The length of a StringBuilder cannot exceed its capacity. 
D) Both a and b are true.

Question 18

Which of the following is not a method of class String?

Accepted Answer

A) toUpperCase 
B) trim 
C) toCharacterArray 
D) All of the above are methods of class String 
A) toUpperCase 
B) trim 
C) toCharacterArray 
D) All of the above are methods of class String

Question 19

String objects are immutable.This means they ________.

Accepted Answer

A) must be initialized 
B) cannot be deleted 
C) cannot be changed 
D) None of the abov 
A) must be initialized 
B) cannot be deleted 
C) cannot be changed 
D) None of the abov

Question 20

The statement
S1)equalsIgnoreCase(s4)
Is equivalent to which of the following?

Accepted Answer

A) s1.regionMatches(true,0,s4,0,s4.length()); 
B) s1.regionMatches(0,s4,0,s4.length()); 
C) s1.regionMatches(0,s4,0,s4.length); 
D) s1.regionMatches(true,s4,0,s4.length); 
A) s1.regionMatches(true,0,s4,0,s4.length()); 
B) s1.regionMatches(0,s4,0,s4.length()); 
C) s1.regionMatches(0,s4,0,s4.length); 
D) s1.regionMatches(true,s4,0,s4.length);

Exam 14: Strings

Consider the examples below: a)a string. b)'a string'. c)"a string". d)"1234". e)integer. Which could be the value of a Java variable of type String?

StringBuilder objects can be used in place of String objects if ________.

To find the character at a certain index position within a String,use the method ________.

Which of the following creates the string of the numbers from 1 to 1000 most efficiently?

The length of a string can be determined by ________.

Consider the Java segment: String line1 = new String("c = 1 + 2 + 3"); StringTokenizer tok = new StringTokenizer(line1,"+="); String foo = tok.nextToken(); String bar = tok.nextToken(); The values of foo and bar are:

Which of the following statements is true?

Given the following declaration: StringBuilder buf = new StringBuilder(); What is the capacity of buf?

Which class is not a type-wrapper class?

Consider the statement below: StringBuilder sb1 = new StringBuilder("a toyota"); Which of the following creates a String object with the value "toy"?

Which of the following are static Character methods?

Consider the Java segment: String line1 = new String("c = 1 + 2 + 3"); StringTokenizer tok = new StringTokenizer(line1); Int count = tok.countTokens(); The value of count is ________.

Consider the Java segment: String line1 = new String("c = 1 + 2 + 3"); StringTokenizer tok = new StringTokenizer(line1,delimArg); For the String line1 to have 4 tokens,delimArg should be:

The String method substring returns ________.

How many String objects are instantiated by the following code segment (not including the literals)? String s1,output; S1 = "hello"; Output = "\nThe string reversed is: " ; For (int i = s1.length()- 1;i >= 0;i--) Output += s1.charAt(i)+ " " ;

Which of the following will create a String different from the other three?

Which of the following statements is true?

Which of the following is not a method of class String?

String objects are immutable.This means they ________.

The statement S1)equalsIgnoreCase(s4) Is equivalent to which of the following?

Introduction to Computers and Java

Introduction to Java Applications

Introduction to Classes and Objects

Control Statements: Part 1

Control Statements: Part 2

Methods: a Deeper Look

Arrays and Arraylists

Classes and Objects: a Deeper Look

Object Oriented Programming: Inheritance

Object-Oriented Programming: Polymorphism

Exception Handling

Gui Components: Part 1

Graphics and Java 2D

Files,streams and Object Serialization

Generic Collections

Lambdas

Recursion

Searching, Sorting and Big O

Generic Classes and Methods

Custom Generic Data Structures

Concurrency

Accessing Databases With Jdbc

JavaFX

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