Ch. 7 - Arrays and the ArrayList Class

What do you normally use with a partially-filled array?

An accompanying integer value that holds the number of items stored in the array

What will be returned from the following method? public static float[] getValue(int x)

An array of float values

TRUE/FALSE: A sorting algorithm is used to locate a specific item in a larger collection of data.

False

TRUE/FALSE: An array can hold multiple values of several different data types simultaneously.

False

TRUE/FALSE: If a[] and b[] are two integer arrays, the expression a == b compares the array contents.

False

TRUE/FALSE: Java limits the number of dimensions that an array may have to 15.

False

This indicates the number of elements, or values, the array can hold.

The array's size declarator

TRUE/FALSE: A sorting algorithm is a technique for scanning through an array and rearranging its contents in some specific order.

True

TRUE/FALSE: Java does not limit the number of dimensions that an array may have.

True

The binary search algorithm:

Will cut the portion of the array being searched in half each time the loop fails to locate the search value

This ArrayList class method deletes an item from an ArrayList.

remove

You can use this ArrayList class method to replace an item at a specific location in an ArrayList.

set

Given that String[] str has been initialized, to get a copy of str[0] with all characters converted to upper case, use the following statement:

str[0].toUpperCase();

By default, Java initializes array elements with what value?

0

Subscript numbering always starts at what value?

0

What does the following statement do? double[] array1 = new double[10];

All of the above (Declares array1 to be a reference to an array of double values, Creates an instance of an array of 10 double values, & Will allow valid subscripts in the range of 0 - 9)

This ArrayList class method is used to insert an item into an ArrayList.

add

You can use this ArrayList class method to insert an item at a specific location in an ArrayList.

add

In memory, an array of String objects:

Consists of elements, each of which is a reference to a String object

Each array in Java has a public field named ____________ that contains the number of elements in the array.

length

What is the value of scores[2][3] in the following array? int [] [] scores = { {88, 80, 79, 92, {75, 84, 93, 80}, {98, 95, 92, 94}, {91, 84, 88, 96} };

94

You use this method to determine the number of items stored in an ArrayList object.

numberItems

If numbers is a two-dimensional array, which of the following would give the length of row r?

numbers[r].length

The following statement creates an ArrayList object. What is the purpose of the <String> notation? ArrayList<String> arr = new ArrayList<String>();

It specifies that only String objects may be stored in the ArrayList object.

In order to do a binary search on an array:

The array must first be sorted in ascending order

To return an array of long values from a method, use this as the return type for the method.

long[]

Which of the following is a correct method header for receiving a two-dimensional array as an argument?

public static void passArray(int [][])

What do you call the number that is used as an index to pinpoint a specific element within an array?

subscript

If final int SIZE = 15 and int[] x = new int[SIZE], what would be the range of subscript values that could be used with x[]?

0 through 14

For the following code, what would be the value of str[2]? String[] str = {"abc", "def", "ghi", "jkl"};

A reference to the String "ghi"

A ragged array is:

A two-dimensional array where the rows are of different lengths

When an array is passed to a method:

All of the above (A reference to the array is passed, It is passed just as an object, & The method has direct access to the original array)

In Java, you do not use the new operator when you use an:

Initialization list

When an individual element of an array is passed to a method:

The method does not have direct access to the original array

TRUE/FALSE: Objects in an array are accessed with subscripts, just like any other data type in an array

True

TRUE/FALSE: Once an array is created, its size cannot be changed.

True

TRUE/FALSE: The String[] args parameter in the main method header allows the program to receive arguments from the operating system command-line.

True

TRUE/FALSE: To compare the contents of two arrays, you must compare the elements of the two arrays.

True

TRUE/FALSE: When an array of objects is declared, but not initialized, the array values are set to null.

True

TRUE/FALSE: Any items typed on the command-line, separated by space, after the name of the class are considered to be one or more arguments that are to be passed into the main method.

True

TRUE/FALSE: Declaring an array reference variable does not create an array.

True

The sequential search algorithm:

Uses a loop to sequentially step through an array, starting with the first element

TRUE/FALSE: An ArrayList object automatically expands in size to accommodate the items stored in it.

True

A search algorithm:

Is a way to locate a specific item in a larger collection of data

The ArrayList class is in this package.

java.util

Java performs ____________, which means that it does not allow a statement to use a subscript that is outside the range of valid subscripts for the array.

Array bounds checking

It is common practice to use a ____________ variable as a size declarator.

final