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.

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  A、put Poker.jar in directory /stuff/java，and set the CLASSPATH to include /stuff/java

  B、put Poker.jar in directory /stuff/java，and set the CLASSPATH to include /stuff/java/*.jar

  C、Put Poker.jar in directory /stuff/java，and set the CLASSPATH to include /stuff/java/Poker.jar

  D、put Poker.jar in directory /stuff/java/games/cards，and set the CLASSPATH to include /stuff/java

  E、put Poker.jar in directory /stuff/java/games/cards，and set the CLASSPATH to include /stuff/java/*.jar

  F、put Poker.jar in directory /stuff/java/games/cards，and set the CLASSPATH to include /stuff/java/Poker.jar

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• What is the result？（）

  A、 Cat

  B、 Dog

  C、 Compilation fails.

  D、 The code runs with no output.

  E、 An exception is thrown at runtime.

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• Which&ensp；can&ensp；be&ensp；used&ensp；to&ensp；encode&ensp；charS&ensp；for&ensp；output？（）

  A、 Java.io.OutputStream.

  B、 Java.io.OutputStreamWriter.

  C、 Java.io.EncodeOutputStream.

  D、 Java.io.EncodeWriter.

  E、 Java.io.BufferedOutputStream.

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• Given that a static method doIt（） in a class Work represents work to be done， what block of code will succeed in starting a new thread that will do the work？   CODE BLOCK a：   Runnable r = new Runnable（） {   public void run（） {   Work.doIt（）；   }   }；   Thread t = new Thread（r）；   t.start（）；   CODE BLOCK b：   Thread t = new Thread（） {  public void start（） {   Work.doIt（）；  }  }；   t.start（）；   CODE BLOCK c：   Runnable r = new Runnable（） {   public void run（） {   Work.doIt（）；   }   }；   r.start（）；  CODE BLOCK d：   Thread t = new Thread（new Work（））；   t.start（）；   CODE BLOCK e：   Runnable t = new Runnable（） {   public void run（） {   Work.doIt（）；   }   }；   t.run（）；  

  A、Code block a.

  B、Code block B.

  C、Code block c.

  D、Code block d.

  E、Code block e.

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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.

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