Ch 7: Characters, Strings, and the StringBuilder
The creators of Java chose ____ characters as the "extra" length for a StringBuilder object.
16
The ____ class contains standard methods for testing the values of characters.
Character
Any string value that is input into a program can be used in arithmetic operations.
False
If you try to use an index that is greater than 0 or less than the index of the last position in the StringBuilder object, you cause an error known as an exception and your program terminates.
False
The StringBuffer class is more efficient than the StringBuilder class because it can execute multiple threads during program execution.
False
The methods islowerCase() and toLowerCase() perform the same tasks.
False
The terms "literal string" and "string literal" have different meanings in Java programming.
False
When working with Strings, it is necessary to explicitly set a String to null.
False
When you compare Strings with the == operator, you are comparing their values, not their memory addresses.
False
To convert a String to an integer, you use the ____ class, which is part of java.lang and is automatically imported into programs you write.
Integer
Which of the following correctly declares and initializes a String object?
String greeting = "Hello";
A named object of the String class
String variable
A ____ is a class for storing and manipulating changeable data that is composed of multiple characters.
StringBuilder
A String variable name is not a simple data type.
True
In a compareTo() method, programmers often do not need specific return values but want to determine if a value is positive or negative.
True
When you must determine whether a String is empty, it is more efficient to compare its length to 0 than it is to use the equals () method.
True
A literal string is a(n) ____ object.
anonymous
A literal string is called a(n) ____.
anonymous object
An unnamed object
anonymous object
Add characters to the end of a StringBuilder object
append()
A StringBuilder object contains a memory block called a _____, which might or might not contain a string.
buffer
A memory block
buffer
Memory block
buffer
The method header of the equals() method within the String class is ____. a. public boolean equals(Strings) b. private boolean equals(String s) c. public boolean equals(String s) d. public boolean equals(Character s)
c. public boolean equals(String s)
Length of a buffer
capacity
The ____ method requires an integer argument that indicates the position of the character at that position, starting at 0.
charAt()
When the String class ____ method is used to compare two Strings, it provides additional information to the user in the form of an integer value.
compareTo()
Appending strings
concatenation
System.out.println("Your name is " + yourName); The above statement is an example of ____, which is used to join Strings.
concatenation
The String class ____ method evaluates the contents of two String objects to determine if they are equivalent.
equals()
The String class ____ method is similar to the equals() method. As its name implies, this method does not consider case when determining if two Strings are equivalent.
equalsCase()
Object that can't be changed
immutable
Strings and other objects that can't be changed are known as ____.
immutable
Determines whether a specific character occurs within a String
indexOf()
The Character class ____ from java.lang.Object.
inherits
Add characters at a specific location within a StringBuilder object
insert()
The ____ method lets you add characters at a specific location within a StringBuilder object.
insert()
The ____ method returns the length of a String.
length()
A(n) ____ comparison is based on the integer Unicode values of the characters.
lexicographical
String oneStr = "Welcome Jim" String twoStr = "Welcome Joe" Given the lines of code above, which of the following regionMatches() expressions will result in a value of true?
oneStr.regionMatches(0, twoStr, 0, 7)
Takes a String argument and returns its double value
parseDouble()
The ____ method takes a String argument and returns its double value.
parseDouble()
Assume that aName refers to Roger. What is returned by aName.compareTo("Robert");
positive number
A(n) ____ is a variable that holds a memory address.
reference
The ____ method allows you to replace all occurrences of some character within a String.
replaceCharacter()
To alter just one character in a StringBuilder, you can use the ____ method, which allows you to change a character at a specified position within a StringBuilder object.
setCharAt()
Change the length of a string in a StringBuilder object
setLength()
Consider the statement: int anInt = Integer.parseInt("649"); You can tell that parseInt() is a(n) ____ method because you use it with the class name and not with an object.
static
The ____ method and the startsWith() method each take a String argument and return true or false if a String object does or does not end or start with the specified argument, respectively.
strEnd()
Takes two integer arguments: a start position and an end position
substring()
The methods of the Character class that begin with ____ return a character that has been converted to the stated format.
to
Returns the lowercase equivalent of the argument
toLowerCase()
The ____ method converts any object to a String.
toString()
When you declare a variable of a basic, primitive type, such as int x = 10;, the memory address where x is located holds the ____.
value of 10
Class or object that wraps around a simpler element
wrapper