String s = strings.get(0);
Iterator i1 = strings.iterator();
String[] array1 = strings.toArray();
Iterator
String[] array2 = strings.toArray(new String[1]);
Iterator
第1题:
1. public class A { 2. void A() { 3. System.out.println(“Class A”); 4. } 5. public static void main(String[] args) { 6. new A(); 7. } 8. } What is the result?()
第2题:
1. import java.util.*; 2. class ForInTest { 3. static List list = new ArrayList(); 4. 5. static List getList() { return list; } 6. 7. public static void main(String [] args) { 8. list.add("a"); list.add("b"); list.add("c"); 9. // insert code here 10. System.out.print(o); 11. } 12. } 第 9 行插入哪一项将输出 abc?()
第3题:
1. public interface A { 2. public void doSomething(String thing); 3. } 1. public class AImpl implements A { 2. public void doSomething(String msg) { } 3. } 1. public class B { 2. public A doit() { 3. // more code here 4. } 5. 6. public String execute() { 7. // more code here 8. } 9. } 1. public class C extends B { 2. public AImpl doit() { 3. // more code here 4. } 5. 6. public Object execute() { 7. // more code here 8. } 9. } Which statement is true about the classes and interfaces in the exhibit?()
第4题:
Given classes defined in two different files: 1. package util; 2. public class BitUtils { 3. public static void process(byte[]) { /* more code here */ } 4. } 1. package app; 2. public class SomeApp { 3. public static void main(String[] args) { 4. byte[] bytes = new byte[256]; 5. // insert code here 6. } 7. } What is required at line 5 in class SomeApp to use the process method of BitUtils?()
第5题:
1. import java.util.*; 2. public class Example { 3. public static void main(String[] args) { 4. // insert code here 5. set.add(new integer(2)); 6. set.add(new integer(l)); 7. System.out.println(set); 8. } 9. } Which code, inserted at line 4, guarantees that this program will output [1,2]? ()
第6题:
import java.util.*; public class LetterASort { public static void main(String[] args) { ArrayList
第7题:
Given a class Repetition: 1.package utils; 2. 3.public class Repetition{ 4.public static String twice(Strings){returns+s;} 5.} and given another class Demo: 1.//insert code here2. 3.public class Demo{ 4.public static void main(String[]args){ 5.System.out.println(twice("pizza")); 6.} 7.} Which code should be inserted at line 1 of Demo.java to compile and run Demo to print“pizzapizza”?()
第8题:
1. public class Test { 2. public static void main (String args) { 3. unsigned byte b = 0; 4. b--; 5. 6. } 7. } What is the value of b at line 5?()
第9题:
Given classes defined in two different files: 1. package util; 2. public class BitUtils { 3. private static void process(byte[] b) { } 4. } 1. package app; 2. public class SomeApp { 3. public static void main(String[] args) { 4. byte[] bytes = new byte[256]; 5. // insert code here 6. } 7. } What is required at line 5 in class SomeApp to use the process method of BitUtils?()
第10题:
1. public class enclosingone ( 2. public class insideone{} 3. ) 4. public class inertest( 5. public static void main (string[]args)( 6. enclosingone eo= new enclosingone (); 7. //insert code here 8. ) 9. ) Which statement at line 7 constructs an instance of the inner class?()