Java I/O Streams and String Handling

This is the correct answer. Streams can be used to input and output the data. They are of two types :-Byte Stream :- for handling binary data.Character Stream :- for handling data such as sequence of characters. Thus this is the correct answer.

This is the correct answer because as I explained all of the given methods are defined in the OutputStream class.

As I explained all of the methods are defined in the Input Stream class. So this is the correct choice.

There are five subclasses of OutputStream class are the. These are: 1.) FileOutputStream :- for writing bytes into file. 2.) ObjectOutputStream:- for writing objects and primitive data types to output stream. 3.) ByteArrayOutputStream:- For output stream that writes byte into array. 4.) pipedOutputStream :- for writing into a piped stream. 5.) FilterOutputStream :- for filtering output into an existing stream. So this is the correct answer.

As I explained both option 1 and 2 are correct. So this is the correct choice.

This is the correct answer. there are 7 subclasses of InputStream class.hese are :-1.) FileInputStream :- for reading bytes from a file.2.) ObjectInputStream :- for readin objects and primitive data types from input stream.3.) SequenceInputStream :- for readin from a sequence of streams.4.) ByteArrayInputStream :- for Stream that reads a byte array.5.) pipedInputStream :- for reading from a piped stream.6.) FilterInputStream :- for filtering input from Existing Stream.7.) StringBufferInputStream:- for readin from a string. These are the 7 subclasses. So this is the correct answer.

This is an incorrect answer. Character stream class is defined by using two class hierarchies. These classes are: 1.) Reader class 2.) Writer class. So this is the incorrect answer.

This is the correct answer. Byte stream can be defined by using two class hierarchies. These two classes are : 1.) InputStream 2.) OutputStream. So this is the correct answer.

There are 6 subclasses of reader Class in Java. These are: 1.) BufferedReader :- for buffering other readers. 2.) ChararrayReader :- For reading from char array. 3.) FilterReader :- For readin filter streams. 4.) InputStreamReader :- For reading a character stream. 5.) PipedReader :- for reading from pipe. 6.) StringReader :- for reading from a string. So this is the correct answer.

As I explained all of the methods are defined in the Reader class. So this is the correct choice.

There is no subclass of Reader class named InputReader. The correct name is InputStreamReader used for reading a character stream. So this is the correct answer.

This is the correct answer. There is no Subclass named charWriter. The correct name is CharArrayWriter which is used for writing to a char array. So this is the correct answer.

As I explained both the classes in option 2 & 3 are the only subclasses of InputStream class. So this is the correct answer.

As I explained that all of the given methods are defined in the File class. So this is the correct answer.

There are 7 subclasses of Writer class in Java. These are: 1.) OutputStreamWrite :- for writing a character stream. 2.) BufferedWriter:- for buffering other writers. 3.) PrintWriter :- for writing formatted data. 4.) PipedWriter:- for writing to a pipe. 5.) CharArrayWriter:- for writing to a char array. 6.) StringWriter:- for writing to a string. 7.) FilterWriter:- for writing filtered streams  So this is the correct answer.

This is the correct answer. S.length() wil return 15 because there are 15 characters in the String. So the code looks like this :-s.charAt(15);the index count starts at 0. In this way the last character a is at index number 14. So if we try to access a character in a string which is out of bound then a runtime exception “StringOutOfBound” will be thrown. So we can pass only till s.charAt(s.length()-1). So this is correct answer.

As I explained the reason all of the functions are defined in the String class. So this is the correct answer.

This is the correct answer. Substring method takes two parameters (beginIndex,EndIndex).Substring( int Begin , int End). It return the string from begin to end – 1. But if the begin index is greater than the endindex then a runtime error will occur. So here substring(4,3) will give runtime error. So this is the correct answer.

This is the correct answer. Because there is no method defined in the String class named toLower(). So it cannot be invoked using the object of String class.The correct method is toLowerCase() which converts the characters to lowercase. So this is the correct answer.

This is the correct answer. The compiler will throw an error that method match() was not declared. Because String class do not contains any method named match(). The correct method is matches(). So the above statement should be s.matches(s1). So this is the correct answer.