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

There is a big tree____the house.A.in the front ofB.in front ofC.in frontD.at class

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