1. FileInputStream for input and FileOutputStream for output must be used.
2. Data in binary format is read or written by InputStream and OutputStream. You cannot use read(byte b) or write(byte b) for InputStream and Outstream, because they are abstract methods.
3. The value of a byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned.
4. Characters are read or written by the Reader and Writer classes. read() or write(char c) can be used in those streams.
5. The byte stream is a stream of bytes, and the character stream is a stream of characters. Different classes are used to handle these streams.
6. Bytes are read or written using file streams. You can use read() or write(byte b) in file streams.
7. The data streams (DataInputStream and DataOutputStream) read and write Java primitive types in a machine-independent fashion, which enables you to write a data file on one machine and read it on another machine with a different operating system or file structure. They are often used for importing and exporting data.
8. They are very similar except that PrintStream is used to print things on the console and DataOutputStream is used with FileWriter to write things into a file.
9. JFileChooser is modal. getSelectedFile() returns an instance of File. getSelectedDirectories() returns an instance of File[]. Use setCurrentDirectory(new File(".")) to set current directory as default directory for JFileChooser.
10. InputStream
System.in
PrintStream System.out
PrintStream System.err
11.
Any objects that are instance of
Serializable can be stored using the object stream. You use the writeObject
method to write an object to the object output stream and use readObject to
read an object from the object input stream. The readObject method returns a
value of the Object type. A static variable is not serialized. If you don’t
want a variable to be serialized, mark it transient.
12. Yes, because they share the same interface for reading and writing data in the same format.
13. RandomAccessFile
raf = new RandomAccessFile("student.dat", "rw");
DataOutputStream
outfile = new DataOutputStream(new FileWriter("student.dat"));
To create a RandomAccessFile stream, you simply use the RandomAccessFile constructor. To create a DataOutputStream, you use DataOutputStream wrapped on FileWriter.
14. It will
compile fine, but raises a run time exception.
15. When do you use StreamTokenizer?
Answer: You use StreamTokenizer when processing text files.
How do you read data using StreamTokenizer?
Answer: To create a StreamTokenizer object, you need to create it wrapped on FileWriter.
Where is the token stored when you are using the nextToken() method?
Answer: The nextToken is stored in the in_sval variable.
How do you find the data type of the token?
Answer: To find the data type of the token, use the in_type variable.
16. No.