for(Object o : list)
for(Iterator o : list)
for(Object o : list.iterator())
for(Iterator o : list.iterator(); o.hasNext (); )
第1题:
现有包结构: com |-- x | |-- Alpha.class | | | |-- y | |-- Beta.class | |-- Gamma.class 和类: //insert code here import com.*; import com.x.y.*; class Test { Alpha a; Beta b; Gamma c; } 哪两行分别插入后可允许代码编译?()
第2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3题:
A、%@import=”java.util.*”%
B、%@import=”java.util.*”@%
C、%@pageimport=”java.util.*”%
D、%@pagejava=”java.util.*”%
第4题:
1. public class returnIt ( 2. returnType methodA(byte x, double y) ( 3. return (short) x/y * 2; 4. ) 5. ) What is the valid returnType for methodA in line 2?()
第5题:
与page指令<%@ page import= “java.util.*, java.text.* “ %> 等价的是()。
第6题:
1. public class Target { 2. private int i = 0; 3. public int addOne() { 4. return ++i; 5. } 6. } And: 1. public class Client { 2. public static void main(String[] args) { 3. System.out.println(new Target().addOne()); 4. } 5. } Which change can you make to Target without affecting Client?()
第7题:
Given a file GrizzlyBear.java: 1. package animals.mammals; 2. 3. public class GrizzlyBear extends Bear { 4. void hunt() { 5. Salmon s = findSalmon(); 6. s.consume(); 7. } 8. } and another file, Salmon.java: 1. package animals.fish; 2. 3. public class Salmon extends Fish { 4. void consume() { /* do stuff */ } 5. } Assume both classes are defined in the correct directories for theft packages, and that the Mammal class correctly defines the findSalmon() method. Which two changes allow this code to compile correctly?()
第8题:
现有: 3.import java.util.*; 4.class ForInTest { 5.static List list = new ArrayList(); 6.public static void main (String [] args){ 7. 8.list.add("a"); list.add("b"); list.add("c"); 9.//insert code here 10.System.out.print(o); } } 哪一行插入到第9行将导致输出“abc”?()
第9题:
现有: 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 (Strincj[] 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10题:
ClassOne.java: 1. package com.abe.pkg1; 2. public class ClassOne { 3. private char var = ‘a’; 4. char getVar() { return var; } 5. } ClassTest.java: 1. package com.abe.pkg2; 2. import com.abc.pkg1.ClassOne; 3. public class ClassTest extends ClassOne { 4. public static void main(String[] args) { 5. char a = new ClassOne().getVar();6. char b = new ClassTest().getVar(); 7. } 8. } What is the result?()