现有: class Tree { private static String tree = "tree "; String getTree () { return tree; } } class Elm extends Tree { private static String tree = "elm "; public static void main (String [] args) { new Elm() .go (new Tree()) ; } } void go (Tree t) { String s = t.getTree () +Elm.tree + tree + (new Elm() .getTree ()) ; System.out.println (s) ;} 结果为:() A、 elm elm elm elmB、 tree elm elm elmC、 tree elm elm treeD、 tree elm tree elm
现有: class Tree { private static String tree = "tree "; String getTree () { return tree; } } class Elm extends Tree { private static String tree = "elm "; public static void main (String [] args) { new Elm() .go (new Tree()) ; } } void go (Tree t) { String s = t.getTree () +Elm.tree + tree + (new Elm() .getTree ()) ; System.out.println (s) ;} 结果为:()
- A、 elm elm elm elm
- B、 tree elm elm elm
- C、 tree elm elm tree
- D、 tree elm tree elm
相关考题:
现有如下包结构:com|--x||--Alpha.class||||--y||--Beta.class||--Gamma.class和类:classTest{Alphaa;Betab;Gammac;}哪三个必须加入到类Test中,以使其通过编译?() A.packagey;B.packagecom;C.importcom.x.*;D.importcom.x.y.*
现有:classTree{privatestaticStringtree=tree;StringgetTree(){returntree;}}classElmextendsTree{privatestaticStringtree=elm;publicstaticvoidmain(String[]args){newElm().go(newTree());}}voidgo(Treet){Strings=t.getTree()+Elm.tree+tree+(newElm().getTree());System.out.println(s);}结果为:()
现有两个类A,B,以下描述中表示B继承自A的是 ( )A.class A extends BB.class B implements AC.class A implements BD.class B extends A
下面程序段的输出结果为 public class Test { public static void main(String args[]) { boolean a,b,c; a=(35); b=(a==true); System.out.println(”a=”+a+”b=+b) ; c=(b==false); System.out.printhln(”b=”+b+”c=”+c) ; } }A.a=true b=false b=true c=falseB.a=true b=false b=true c=trueC.a=true b=true b=tree c=falseD.a=false b=false b=tree c=false
考虑如下代码:class Tree{}class Pine extends Tree{}class Oak extends Tree{}public class Forest {public static void main( String[] args ) {Tree tree = new Pine();if( tree instanceof Pine )System.out.println( "Pine" );if( tree instanceof Tree )System.out.println( "Tree" );if( tree instanceof Oak )System.out.println( "Oak" );elseSystem.out.println( "Oops" );}}则输出结果中有哪些?A.Pine B.Tree C.Forest D.Oops E.无输出
Which command enhances the 802.1D convergence time on ports that are connected to hosts?() A. spanning-tree backbonefastB. spanning-tree uplinkfastC. spanning-tree portfastD. spanning-tree cost512
Which command enables RSTP on a switch?() A. spanning-tree mode rapid-pvstB. spanning-tree uplinkfastC. spanning-tree backbonefastD. spanning-tree mode mst
Draw a labeled constituent structure tree diagram for each of the following sentences: 1) The student likes the new linguistics professor. 2) John suggested Mary take the linguistics class.
Which two of these statements correctly describe classic PIM-SM?()A、The IOS default is for a last-hop router to trigger a switch to the shortest path tree as soon as a new source is detected on the shared tree.B、The IOS default is for every one of the routers on the shared tree to trigger a switch to the shortest path tree as soon as a new source is detected on the shared tree.C、The default behavior of switching to the shortest path tree as soon as a new source is detected on the shared tree can be disabled by setting the value in the ip pim spt-threshold command to "infinity."D、The default behavior of switching to the shortest path tree as soon as a new source is detected on the shared tree can be disabled by setting the value in the ip pim spt-threshold command to "zero."
What is the Cisco IOS default behavior for switching from the shared tree to the shortest path tree in PIM-SM operations?()A、immediately after receiving the first packet on the shared tree for a given (S,G)B、after receiving over 1 kb/s traffic onthe shared tree for a given (S,G)C、10 seconds after receiving the first packet on the shared tree for a given (S,G)D、30 seconds after receiving the first packet on the shared tree for a given (S,G)E、after receiving over 10 kb/s traffic onthe shared tree for a given (S,G)
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?() A、package com.;B、import com.x;C、package com.x;D、import com.x.Alpha;
现有如下包结构: com |-- x | |-- Alpha.class | | | |-- y | |-- Beta.class | |-- Gamma.class 和类: class Test { Alpha a; Beta b; Gamma c; } 哪三个必须加入到类 Test 中,以使其通过编译?()A、package y;B、package com;C、import com.x.*;D、import com.x.y.*
Which command enables RSTP on a switch?()A、spanning-tree mode rapid-pvstB、spanning-tree uplinkfastC、spanning-tree backbonefastD、spanning-tree mode mst
Which command enhances the 802.1D convergence time on ports that are connected to hosts?()A、spanning-tree backbonefastB、spanning-tree uplinkfastC、spanning-tree portfastD、spanning-tree cost512
现有: class A {public String name="a"} class B extends A {public String name="b"} 执行如下代码后的结果是哪项?() A a=new B(); System.out.println(a.name); A、 aB、 bC、编译失败D、运行时抛出异常
final class Tree { private static String tree = "tree "; String getTree() { return tree; } } class Elm extends Tree { private static String tree = "elm "; public static void main(String [] args) { new Elm().go(new Tree()); } void go(Tree t) { String s = t.getTree()+Elm.tree+tree+(new Elm().getTree()); System.out.println(s); } } 结果为:() A、elm elm elm elmB、tree elm elm elmC、tree elm tree elmD、编译失败
public class Plant { private String name; public Plant(String name) { this.name = name; } public String getName() { return name; } } public class Tree extends Plant { public void growFruit() { } public void dropLeaves() { } } Which is true?() A、 The code will compile without changes.B、 The code will compile if public Tree() { Plant(); } is added to the Tree class.C、 The code will compile if public Plant() { Tree(); } is added to the Plant class.D、 The code will compile if public Plant() { this(”fern”); } is added to the Plant class.E、 The code will compile if public Plant() { Plant(”fern”); } is added to the Plant class.
import java.io.*; public class Forest implements Serializable { private Tree tree = new Tree(); public static void main(String [] args) { Forest f= new Forest(); try { FileOutputStream fs = new FileOutputStream(”Forest.ser”); ObjectOutputStream os = new ObjectOutputStream(fs); os.writeObject(f); os.close(); } catch (Exception ex) { ex.printStackTrace(); } } } class Tree { } What is the result?() A、 Compilation fails.B、 An exception is thrown at runtime.C、 An instance of Forest is serialized.D、 A instance of Forest and an instance of Tree are both serialized.
单选题哪个命令可以在交换机启用RSTP? ()A spanning-tree mode rapid-pvstB spanning-tree uplinkfastC spanning-tree backbonefastD spanning-tree mode mst
单选题Which spanning-tree command would cause a PortFast-enabled interface to lose its PortFast-operational status and disable BPDU filtering if it receives BPDUs?()Aspanning-tree guard rootBspanning-tree portfast bpduguard defaultCspanning-tree bpduguard enableDspanning-tree bpdufilter enableEspanning-tree portfast bpdufilter default
单选题现有: class Tree { private static String tree = "tree "; String getTree () { return tree; } } class Elm extends Tree { private static String tree = "elm "; public static void main (String [] args) { new Elm() .go (new Tree()) ; } } void go (Tree t) { String s = t.getTree () +Elm.tree + tree + (new Elm() .getTree ()) ; System.out.println (s) ;} 结果为:()A elm elm elm elmB tree elm elm elmC tree elm elm treeD tree elm tree elm
单选题import java.io.*; public class Forest implements Serializable { private Tree tree = new Tree(); public static void main(String [] args) { Forest f= new Forest(); try { FileOutputStream fs = new FileOutputStream(”Forest.ser”); ObjectOutputStream os = new ObjectOutputStream(fs); os.writeObject(f); os.close(); } catch (Exception ex) { ex.printStackTrace(); } } } class Tree { } What is the result?()A Compilation fails.B An exception is thrown at runtime.C An instance of Forest is serialized.D A instance of Forest and an instance of Tree are both serialized.
单选题public class Plant { private String name; public Plant(String name) { this.name = name; } public String getName() { return name; } } public class Tree extends Plant { public void growFruit() { } public void dropLeaves() { } } Which is true?()A The code will compile without changes.B The code will compile if public Tree() { Plant(); } is added to the Tree class.C The code will compile if public Plant() { Tree(); } is added to the Plant class.D The code will compile if public Plant() { this(”fern”); } is added to the Plant class.E The code will compile if public Plant() { Plant(”fern”); } is added to the Plant class.
单选题Which command enables RSTP on a switch?()Aspanning-tree mode rapid-pvstBspanning-tree uplinkfastCspanning-tree backbonefastDspanning-tree mode mst
单选题final class Tree { private static String tree = "tree "; String getTree() { return tree; } } class Elm extends Tree { private static String tree = "elm "; public static void main(String [] args) { new Elm().go(new Tree()); } void go(Tree t) { String s = t.getTree()+Elm.tree+tree+(new Elm().getTree()); System.out.println(s); } } 结果为:()Aelm elm elm elmBtree elm elm elmCtree elm tree elmD编译失败
单选题现有: interface Animal { void eat () ; } //insert code here public class HouseCat extends Feline { public void eat() { } } 和五个申明 abstract class Feline implements Animal { } abstract class Feline implements Animal { void eat () ; } abstract class Feline implements Animal { public void eat();} abstract class Feline implements Animal { public void eat() {} } abstract class Feline implements Animal { abstract public void eat();} 结果为:()A1B2C3D4