单选题现有:      class TestA  {  public void start()  {  System.out.println("TestA");  }     }  public class TestB extends TestA  {  public void start()  {  System.out.println("TestB");  }     public static void main (string[]  args)  (     ((TestA)new TestB()).start();     )     }  运行结果是哪项?()A  TeStAB  TeStBC编译失败D运行时抛出异常

单选题
现有:      class TestA  {  public void start()  {  System.out.println("TestA");  }     }  public class TestB extends TestA  {  public void start()  {  System.out.println("TestB");  }     public static void main (string[]  args)  (     ((TestA)new TestB()).start();     )     }  运行结果是哪项?()
A

  TeStA

B

  TeStB

C

编译失败

D

运行时抛出异常


参考解析

解析: 暂无解析

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单选题现有      public class Parentt      public void change (int x){)     )      public class Child extends Parent{     //覆盖父类change方法     }      下列哪个声明是正确的覆盖了父类的change方法?()A  protected void change (int x){}B  public void change(int x,  int y){}C  public void change (int x){}D  public void change (String s){}

单选题class super (   public int I = 0;   public super (string text) (   I = 1   )   )     public class sub extends super (   public sub (string text) (   i= 2   )   public static void main (straing args) (  sub sub = new sub (“Hello”);   system.out. PrintIn(sub.i);  )   )   What is the result?()A Compilation will fail.B Compilation will succeed and the program will print “0”C Compilation will succeed and the program will print “1”D Compilation will succeed and the program will print “2”

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单选题public class TestA{   public void methodA()  throws IOException{   //……   }   }   public class TestB extends TestA{   public void methodA()  throws EOFException{   //……   }   }   public class TestC extends TestA{   public void methodA()  throws Exception{   //……   }   }   当编译类TestC的时候,结果是哪项?()A 正常B 编译错误C 运行错误D 以上都不对

单选题现有:      class TestA  {  public void start()  {  System.out.println("TestA");  }     }  public class TestB extends TestA  {  public void start()  {  System.out.println("TestB");  }     public static void main (string[]  args)  (     ((TestA)new TestB()).start();     )     }  运行结果是哪项?()A  TeStAB  TeStBC编译失败D运行时抛出异常

单选题class TestA {  public void start() { System.out.println(”TestA”); }  }  public class TestB extends TestA {  public void start() { System.out.println(”TestB”); } public static void main(String[] args) {  ((TestA)new TestB()).start();  }  }  What is the result?()A TestAB TestBC Compilation fails.D An exception is thrown at runtime.

多选题Which two code fragments will execute the method doStuff() in a separate thread?()Anew Thread() { public void run() { doStuff(); } }Bnew Thread() { public void start() { doStuff(); } }Cnew Thread() { public void start() { doStuff(); } } .run();Dnew Thread() { public void run() { doStuff(); } } .start();Enew Thread(new Runnable() { public void run() { doStuff(); } } ).run();Fnew Thread(new Runnable() { public void run() { doStuff(); } }).start();

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