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单选题
现有: 3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 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. } 哪一行插入到第9行将导致输出“abc”?()
A
for(Object o : list)
B
for(Iterator o : list)
C
for(Object o : list.iterator())
D
for(Iterator o : list.iterator(); o.hasNext (); )
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更多 “单选题现有: 3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 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. } 哪一行插入到第9行将导致输出“abc”?()A for(Object o : list)B for(Iterator o : list)C for(Object o : list.iterator())D for(Iterator o : list.iterator(); o.hasNext (); )” 相关考题
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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”?() A、 for(Object o : list)B、 for(Iterator o : list)C、 for(Object o : list.iterator())D、 for(Iterator o : list.iterator(); o.hasNext (); )
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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?()A、 Compilation fails.B、 Compilation succeeds and no exceptions are thrown.C、 An exception is thrown at line 5 in ClassTest.java.D、 An exception is thrown at line 6 in ClassTest.java.
考题
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考题
现有: 3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 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. } 哪一行插入到第9行将导致输出“abc”?() A、 for(Object o : list)B、 for(Iterator o : list)C、 for(Object o : list.iterator())D、 for(Iterator o : list.iterator(); o.hasNext (); )
考题
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考题
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Compilation succeeds but an exception is thrown at line 6 in ClassTest.java.
考题
多选题现有2 个文件: 1. package x; 2. public class X { 3. public static void doX() { System.out.print("doX "); } 4. } 和: 1. class Find { 2. public static void main(String [] args) { 3. //insert code here 4. } 5. } 哪两行分别插入到类Find 的第3 行将编译并产生输出“doX”? ()AdoX();BX.doX();Cx.X.doX();Dx.X myX = new x.X(); myX.doX();
考题
单选题现有: 3. import java.util.*; 4. class ForInTest { 5.static List list=new ArrayList(); 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. } 哪一行插入到第9行将导致输出“abc"?()A
for (Iterator o : list.iterator(); o.hasNext (); )B
for (Iterator 0 : list)C
for (Object o : list.iterator())D
for (Object o : list)
考题
单选题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?()A
process(bytes);B
BitUtils.process(bytes);C
util.BitUtils.process(bytes);D
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import util.BitUtils.*; process(bytes);
考题
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process(bytes);B
BitUtils.process(bytes);C
app.BitUtils.process(bytes);D
util.BitUtils.process(bytes);E
import util.BitUtils. *; process(bytes);F
SomeApp cannot use the process method in BitUtils.
考题
单选题与page指令 等价的是()。A
%@ import="“java.util.*" page=""%@ import="“java.text.*" page=""%@ import="“java.text.*" page=""%@ import="“java.util.*" page=""%@ import="“java.text.*" page=""%@ import="“java.util.*" page=""%@ page import= “java.util.* % %@ page import= “java.text.* “ % B
%@ page import= “java.util.*” , import= “java.text.* “ % C
%@ page import= “java.util.* “ ; % %@ page import= “java.text.* “ ; %D
%@ page import= “java.util.* ; java.text.* “ %
考题
单选题现有: 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”?()A
for(Object o : list)B
for(Iterator o : list)C
for(Object o : list.iterator())D
for(Iterator o : list.iterator(); o.hasNext (); )
考题
单选题3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 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. } 哪一行插入到第9行将导致输出“abc”?()A
for(Object o : list)B
for(Iterator o : list)C
for(Object o : list.iterator())D
for(Iterator o : list.iterator(); o.hasNext (); )
考题
单选题1. import java.util.*; 2. class SubGen { 3. public static void main(String [] args) { 4. //insert code here 5. } 6. } class Alpha { } class Beta extends Alpha { } class Gamma extends Beta { } 和四段代码片段: s1. ArrayList〈? extends Alpha〉 list1 = new ArrayList〈Gamma〉(); s2. ArrayList〈Alpha〉 list2 = new ArrayList〈? extends Alpha〉(); s3. ArrayList〈? extends Alpha〉 list3 = new ArrayList〈? extends Beta〉(); s4. ArrayList〈? extends Beta〉 list4 = new ArrayList〈Gamma〉(); ArrayList〈? extends Alpha〉 list5 = list4; 哪些片段分别插入到第4行,可允许代码编译?()A
只有s1B
只有s3C
只有s1和s3D
只有s1和s4
考题
单选题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?()A
for(char o: list)B
for(Object o: getList())C
for(Object o: getList();)D
for(Object o: o.getList())
考题
多选题现有: 1. import java.util.*; 2. 3. Class FindStuff { 4.public static void main (String[]args) { 5, //insert code here 6. c.put ("X", 123); 7. } 8. } 分别插入到第5行,哪三行允许代码编译?()AMap c= new SortedMap();BHashMap c= new HashMap();CHashMap c= new Hashtalole();DSortedMap c= new TreeMap();EArrayList c= new ArrayList();FMaD c = new LinkedHashMap();
考题
多选题1. public class A { 2. public void method1() { 3. B b=new B(); 4. b.method2(); 5. // more code here 6. } 7. } 1. public class B { 2. public void method2() { 3.C c=new C(); 4. c.method3(); 5. // more code here 6. } 7. } 1. public class C { 2. public void method3() { 3. // more code here 4. } 5. } Given: 25. try { 26. A a=new A(); 27. a.method1(); 28. } catch (Exception e) { 29. System.out.print(”an error occurred”); 30. } Which two are true if a NullPointerException is thrown on line 3 of class C?()AThe application will crash.BThe code on line 29 will be executed.CThe code on line 5 of class A will execute.DThe code on line 5 of class B will execute.EThe exception will be propagated back to line 27.
考题
单选题Given a class Repetition: 1. package utils; 2. 3. public class Repetition { 4. public static String twice(String s) { return s + s; } 5. } and given another class Demo: 1. // insert code here 2. 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”?()A
import utils.*;B
static import utils.*;C
import utils.Repetition.*;D
static import utils.Repetition. *;E
import utils.Repetition.twice();F
import static utils.Repetition.twice;G
static import utils.Repetition.twice;
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