CSc335 Fall04 Practice Midterm Section Leader________ Name ________________________
Assume all imports are present
1. Write the output
ArrayList list = new ArrayList();
list.add("a");
list.add("b");
list.add("c");
ArrayList list2 = new ArrayList();
list2.add("d");
list2.add(list);
list2.add("e");
System.out.println(list2);
2. Place a check mark in the space provide if the line o code compiles
String s1;
Object o1;
Object o2 = new String("abc"); // Compiles ______
Integer anInt = new Object(); // Compiles ______
Integer int2 = (Integer)o1; // Compiles ______
String s2 = o2; // Compiles ______
System.out.println((String)o2); // Compiles ______
System.out.println((Integer)s2); // Compiles ______
3. List 3 differences between a Java interface and a Java abstract class
4. Something about Iterator, perhaps show output
ArrayList list = new ArrayList();
list.add(new Integer(3));
list.add(new Integer(5));
list.add(new Integer(1));
list.add(new Integer(4));
Iterator itr = list.iterator();
System.out.println(itr.hasNext());
System.out.println(itr.next());
System.out.println(itr.next());
System.out.println(itr.next());
5. Write the output of this code fragment
JTextField inputField = new JTextField("123point4");
double input = 0.0;
try
{
input = Double.parseDouble(inputField.getText());
System.out.println("Good");
}
catch (RuntimeException rte)
{
System.out.println("Bad");
}
System.out.println("Ugly");
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