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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.
参考答案
更多 “ 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.” 相关考题
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Public class test ( Public static void stringReplace (String text) ( Text = text.replace (‘j’ , ‘i’); ) public static void bufferReplace (StringBuffer text) ( text = text.append (“C”) ) public static void main (String args[]} ( String textString = new String (“java”); StringBuffer text BufferString = new StringBuffer (“java”); stringReplace (textString); bufferReplace (textBuffer); System.out.printLn (textString + textBuffer); ) ) What is the output?()
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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:()A
elm elm elm elmB
tree elm elm elmC
tree elm tree elmD
编译失败
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单选题在下列程序的空白处,应填入的正确选项是( )。import java.io.*;
public class writeInt{
public static void main(String[] args){
int[] myArray={10,20,30,40};
try{
DataOutputStream dos=new DataOutputStream(new FileOutputStream("ints.dat"));
for(int i=0;i
dos.writeInt(myArray[i]);
dos.close();
System.out.println("Have written binary file ints.dat");
}
}
catch(IOException ioe){
System.out.println("IOException");
}
}
}A
start()B
close()C
read()D
write()
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单选题在下列程序的空白处,应填入的正确选项是( )。import java.io.*;
public class ObjectStreamTest{
public static void main(string args[])throws IOException{
ObjectOutputStream oos=new ObjectOutputStream(new FileOutputStream("serial.bin"));
Java.until.Date d=new Java.until.Date();
oos.______();
ObjectInputStream ois=new ObjectlnputStream(new FileOutputStream("serial.bin"));
try{
java.until.date restoredDate=(Java.until.Date)ois.readObject();
System.out.println("read object back from serial.bin file:"+restoredDate);
}
catch(ClassNotFoundException cnf){
System.out.println("class not found");
}
}A
readObjectB
WriterC
BufferedWriterD
writeObject
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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.
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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
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