Users questions 

How do you read a console?

Joe Ford

How do you read a console?

In Java, there are three ways to read input from a console : System. console (JDK 1.6) Scanner (JDK 1.5)…

  1. System. console.
  2. Scanner. Before JDK 1.6, this is the Scanner way to read input from the console.
  3. BufferedReader + InputStreamReader.

Is available () in Java?

The java. io. FileInputStream. available() method returns number of remaining bytes that can be read from this input stream without blocking by the next method call for this input stream.

Why FileInputStream is used in Java?

A FileInputStream obtains input bytes from a file in a file system. What files are available depends on the host environment. FileInputStream is meant for reading streams of raw bytes such as image data. For reading streams of characters, consider using FileReader .

How does InputStreamReader work in Java?

An InputStreamReader is a bridge from byte streams to character streams: It reads bytes and decodes them into characters using a specified charset . The charset that it uses may be specified by name or may be given explicitly, or the platform’s default charset may be accepted.

What are the two types of I O available in Java?

Java performs I/O through Streams. Byte Stream : It provides a convenient means for handling input and output of byte. Character Stream : It provides a convenient means for handling input and output of characters.

Is BufferedReader faster than scanner?

BufferReader has large buffer of 8KB byte Buffer as compared to Scanner. Scanner is bit slower as it need to parse data as well. BufferReader is faster than Scanner as it only reads a character stream.

What is the difference between BufferedReader and BufferedInputStream?

The Java BufferedReader is similar to the BufferedInputStream but they are not exactly the same. The main difference between BufferedReader and BufferedInputStream is that BufferedReader reads characters (text), whereas the BufferedInputStream reads raw bytes.

What is the difference between BufferedReader and FileReader in Java?

FileReader and BufferedReader are two classes to perform operations on files. The main difference between FileReader and BufferedReader in Java is that FileReader reads characters from a file while BufferedReader reads characters from another Reader.

What is the difference between FileReader and FileInputStream?

1) The first difference is in their type hierarchy, FileReader extends from Reader class while FileInputStream is descendent of InputStream class. 2) The second difference is in their purpose. The FileReader is meant for reading text data while FileInputStream is for reading binary data.

What is FileReader in Java?

Java FileReader class is used to read data from the file. It returns data in byte format like FileInputStream class. It is character-oriented class which is used for file handling in java.

What is the difference between BufferedWriter and FileWriter?

FileWriter writes directly into Files and should be used only when the number of writes is less. BufferedWriter: BufferedWriter is almost similar to FileWriter but it uses internal buffer to write data into File. So if the number of write operations is more, the actual IO operations are less and performance is better.

How do you write to a file in Java?

Java FileWriter Example

  1. package com.javatpoint;
  2. import java.io.FileWriter;
  3. public class FileWriterExample {
  4. public static void main(String args[]){
  5. try{
  6. FileWriter fw=new FileWriter(“D:\\testout.txt”);
  7. fw.write(“Welcome to javaTpoint.”);
  8. fw.close();

How do you write a file?

There are two ways to write in a file.

  1. write() : Inserts the string str1 in a single line in the text file. File_object.write(str1)
  2. writelines() : For a list of string elements, each string is inserted in the text file. Used to insert multiple strings at a single time.

What is BufferedWriter in Java?

Java BufferedWriter class is used to provide buffering for Writer instances. It makes the performance fast. It inherits Writer class. The buffering characters are used for providing the efficient writing of single arrays, characters, and strings.

Articles 

How do you read a console?

Joe Ford

How do you read a console?

In Java, there are three ways to read input from a console : System. console (JDK 1.6) Scanner (JDK 1.5)…

  1. System. console.
  2. Scanner. Before JDK 1.6, this is the Scanner way to read input from the console.
  3. BufferedReader + InputStreamReader.

Which header file is used to manipulate the string?

h

How many objects are used for input and output to a string?

3. How many objects are used for input and output to a string? Explanation: The stringstream, ostringstream, and istringstream objects are used for input and output to a string.

How many parameters can a resize method take?

two parameters

What is the maximum number of parameters that a string constructor can take?

Discussion Forum

Que. How many maximum number of parameters does a string constructor can take?
b. 2
c. 3
d. 4
Answer:3

How do I resize a string in C++?

void string ::resize (size_type num, char c ) num: is the new string length, expressed in number of characters. c: is the character needed to fill the new character space. If num > size() : character c is used to fill space. If num < size() : String is simply resized to num number of characters.

What is resize in C++?

Description. The C++ function std::vector::resize() changes the size of vector. If n is smaller than current size then extra elements are destroyed. If n is greater than current container size then new elements are inserted at the end of vector. If val is specified then new elements are initialed with val.

Can you resize an array in C?

There is no way to resize an array. You can simply create a new array of size 2, then copy all the data from the previous one to the new one. realloc does it for you with dynamic memory.

How do you set a vector size?

We can set the size of a Vector using setSize() method of Vector class. If new size is greater than the current size then all the elements after current size index have null values. If new size is less than current size then the elements after current size index have been deleted from the Vector.

How do you resize a 2d vector?

You have to resize the outer and inner vectors separately. You don’t need to create external loop to resize a 2 dimensional vector (matrix). You can simply do the following one line resize() call: //vector<vector> M; //int m = number of rows, n = number of columns; M.

How do you push back a 2D vector?

Elements can be inserted into a vector using the push_back() function of C++ STL. Below example demonstrates the insertion operation in a vector of vectors. The code creates a 2D vector by using the push_back() function and then displays the matrix.

How do you input a 2D vector?

my problem here: std::vector<vector> d; //std::vector d; cout<<“Enter the N number of ship and port:”<>in; cout<<“\Enter preference etc..:\n”; for(i=0; i>temp; d.

How do I print a 2D vector?

Print “the 2D vector is:”. for (int i = 0; i < v. size(); i++) for (int j = 0; j < v[i]. size(); j++) print the value of 2D vector v[i][j].

What is a 2D vector?

A 2D vector is a vector of the vector. Like 2D arrays, we can declare and assign values to a 2D vector! Assuming you are familiar with a normal vector in C++, with the help of an example we demonstrate how a 2D vector differs from a normal vector below: C++