Which two construct an OutputSream that appends to the file “file.txt”? ()
第1题:
要想以读方式打开文件“D:\File.txt”,以下不能实现目的的语句是()。
A、ifstreaminf("D:\\FilEtxt",ios::in);
B、ifstreaminf("D:\\File.txt");
C、ofstreaminf("D:\\File.txt",ios::out);
D、fstreaminf("D:\\File.txt",ios::in|ios::out);
第2题:
A.InputStreamin=newFileReader(“file.txt”);
B.InputStreamin=newFileInputStream(“file.txt”);
C.InputStreamin=newInputStreamFileReader(“file.txt”,“read”);
D.FileInputStreamin=newFileReader(newFile(“file.txt”));
E.FileInputStreamin=newFileInputStream(newFile(“file.txt”));
第3题:
本题的功能是将文件java2.java复制为文件java2.java.bak。 importjava.io.*; public class java2{ public static void main(String sarg[]){ try{File file=new File("java2.java.bak"); ; FilelnputStream rfile=new FilelnputStream("ja- va2.java"); FileOutputStream wfile=new FileOutputStream ("java2.java.bak"); int c; while( ) wfile.write((char)c); rfile.close; wfile.close; }catch(Exception e){System.out.println("读取文 件的时候发生错误!");} System.out.println("复制操作完成!"); } }
第4题:
( 11 )请在下列程序的空白处,填上适当的内容:
Import java. awt. *;
Import java. util. *;
Class BufferTest{
Public static void main(string args[])
Throws IOException{
FileOutputStream unbuf=
new FileOutputStream( “ test.one ” ) ;
BufferedOutputStream buf=
new 【 11 】 (new FileOutputStream( “ test.two ” ));
System.out.println
( “ write file unbuffered: ” + time(unbuf) + “ ms ” );
System.out.println
( “ write file buffered: ” + time(buf) + “ ms ” );
}
Static int time (OutputStream os)
Throws IOException{
Date then = new Date();
for (int i=0; i<50000; i++){
os.write(1);
}
}
os.close();
return(int)(()new Date()).getTime() - then.getTime());
}
第5题:
下面程序的功能是从键盘读取一行文本并将该文本存储到文件中。当用户运行该程序时,需要输入一行文本并按下回车键。然后在DOS系统提示符处输入type file.txt并按下Enter键,这时屏幕会显示type file.txt的内容。通过这个命令可以验证该程序的功能。请在每条横线处填写一条语句,使程序的功能完整。
注意:请勿改动main()主方法和其他已有的语句内容,仅在横线处填入适当的语句。
源程序文件代码清单如下:
import java.io.*;
public class DoFile
{
public static void main(String args[])
{
byte buffername[]=______[80];
try
{
System.out.println("\nEnter a line to be saved to disk:");
int bytesbleck= ______;
FileOutputStream f=new FileOutputStream("file.txt");
______;
}
catch(Exception e)
{
e.printStackTrace();
}
}
}
第6题:
A.OutputStreamout=newFileOutputStream(“file.txt”);
B.OutputStreamout=newFileOutputStream(“file.txt”,“append”);
C.FileOutputStreamout=newFileOutputStream(“file.txt”,true);
D.FileOutputStreamout=newFileOutputStream(newfile(“file.txt”));
E.OutputStreamout=newFileOutputStream(newFile(“file.txt”)true);
第7题:
A.OutputStreamout=newFileOutputStream(“file.txt”); Out.writeBytes(“/n”);
B.OutputStreamos=newFileOutputStream(“file.txt”,true); DataOutputStreamout=newDataOutputStream(os);out.writeBytes(“/n”);
C.OutputStreamos=newFileOutputStream(“file.txt”); DataOutputStreamout=newDataOutputStream(os);out.writeBytes(“/n”);
D.OutputStreamos=newOutputStream(“file.txt”,true); DataOutputStreamout=newDataOutputStream(os);out.writeBytes(“/n”);
第8题:
A、InputStream in=new FileReader(“file.txt”)
B、InputStream in=new FileInputStream(“file.txt”)
C、InputStream in=new InputStreamFileReader (“file.txt”,“read”)
D、FileInputStream in=new FileReader(new File(“file.txt”))
第9题:
( 34 )在下列程序的空白处,应填入的正确选项是
Import java.io.*;
Pulilc class ObjectStreamTest{
Publilc static void main(string args[]) throws IOException{
ObjectOutputStream s= new ObjectOutputStream
(new FileOutputStream( “ serial.bin ” ));
Java .util.Date d= new Java.util.Date();
Oos___________ (d);
ObjectInputStream is=
new ObjectInputStream(new FileOutputStream( “ serial.bin ” ));
try{
java.util.date restoredDate =
(Java.util.Date) ois.readObject();
System.out.println
( “ read object back from serial.bin file: ”
+ restoredDate);
}
Catch (ClassNotFoundException cnf) {
System.out.println ( “ class not found ” );
}
}
A ) WriterObject
B ) Writer
C )BufferedWriter
D ) WriterObject
第10题:
创建一个向文件“file.txt”追加内容的输出流对象的语句有()。