created: Jan. 06, 2000; revised: 10/05/03, 06/05/06

on ArrayLists and Iterators

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1. Declare and construct an `ArrayList` with an initial capacity of 20 references to `Object`.

 A.    `Object list(20) = new ArrayList() ;` B.    `ArrayList list[20] = new ArrayList() ;` C.    `ArrayList[Object] list = new ArrayList(20) ;` D.    `ArrayList

2. Examine the following code:

```ArrayList<String> list = new ArrayList<String>(10) ;
```

After the code has exectued, what is the capactiy of `list`? What is its size?

 A.    3, 3 B.    3, 10 C.    10, 3 D.    10, 10

3. Examine the following code:

```ArrayList<String> list = new ArrayList<String>(10) ;

```

What element will be at index 2 of the list?

 A.    Eve B.    Andy C.    Bart D.    carl

4. Examine the following code:

```ArrayList<String> list = new ArrayList<String>() ;

```

Which of the following will replace the element "Carl" with "Zoltan" ?

 A.    `list[2] = "Zoltan" ;` B.    `list.set( "Zoltan", "Carl" );` C.    `list.add( "Zoltan", list.indexOf("Carl") );` D.    `list.set( list.indexOf("Carl"), "Zoltan" );`

5. Examine the following code:

```ArrayList<String> list = new ArrayList<String>() ;

```

Which of the following will change the list so that it looks like:

```Andy
Bart
Carl
Doug
Oscar
Elmo
```

 A.    `list.add( 3, "Oscar" ) ;` B.    `list.add( 4, "Oscar" ) ;` C.    `list.set( 3, "Oscar" ) ; ` D.    `list.set( 4, "Oscar" ) ;`

6. Examine the following code:

```ArrayList<String> list = new ArrayList<String>() ;

```

Which of the following will change the list so that it looks like:

```Andy
Bart
Doug
Elmo
```

 A.    `list.remove( 3 );` B.    `list.remove( 2 );` C.    `list.add( 2, null );` D.    `list.set( list.indexOf( "Carl" ), "Doug" );`

7. Examine the following code:

```ArrayList<String> list = new ArrayList<String>() ;

```

Which of the following will change the list so that it looks like:

```Andy
Bart
Carl
Doug
```

 A.    `list.remove( list.size() );` B.    `list.remove( list.size()-1 );` C.    `list.remove( 5 );` D.    `list.clear( "Elmo" );`

8. Examine the following code:

```ArrayList<String> list = new ArrayList<String>() ;

Iterator iter = list.___________________;

while( iter.___________ )
System.out.println( iter.___________ );
```

Fill in the blanks so that the list is printed.

 A.    `iterator()       hasNext()     next() ` B.    `iterator()       next()        nextElement() ` C.    `elements()       empty()       next() ` D.    `iterator()       more()        get() `

9. What `equals()` method must you override when defining a class of objects you expect to hold in a `ArrayList` ?

 A.    `public boolean equals( Object )` B.    `public boolean equals( ArrayList )` C.    `boolean equals( Object )` D.    `private int equals( Object )`

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