Reader read(char[]) method in Java with Examples - GeeksforGeeks

07 Feb, 2019
The read(char[]) method of Reader Class in Java is used to read the specified characters into an array. This method blocks the stream till:
It has taken some input from the stream.
Some IOException has occurred
It has reached the end of the stream while reading.
Syntax:
public int read(char[] charArray)
Parameters: This method accepts a mandatory parameter charArray which is the character array to be written in the Stream.
Return Value: This method returns an integer value which is the number of characters read from the stream. It returns -1 if no character has been read.
Exception: This method throws IOException if some error occurs while input-output.
Below methods illustrates the working of read(char[]) method:
Program 1:
// Java program to demonstrate// Reader read(char[]) method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {              String str = "GeeksForGeeks";              // Create a Reader instance            Reader reader                = new StringReader(str);              // Get the character array            // to be read from the stream            char[] charArray = new char[5];              // Read the charArray            // to this reader using read() method            // This will put the str in the stream            // till it is read by the reader            reader.read(charArray);              // Print the read charArray            System.out.println(                Arrays                    .toString(charArray));              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}
[G, e, e, k, s]

Program 2:
// Java program to demonstrate// Reader read(char[]) method  import java.io.*;import java.util.*;  class GFG {    public static void main(String[] args)    {          try {              String str = "GeeksForGeeks";              // Create a Reader instance            Reader reader                = new StringReader(str);              // Get the character array            // to be read from the stream            char[] charArray                = new char[str.length()];              // Read the charArray            // to this reader using read() method            // This will put the str in the stream            // till it is read by the reader            reader.read(charArray);              // Print the read charArray            System.out.println(                Arrays                    .toString(charArray));              reader.close();        }        catch (Exception e) {            System.out.println(e);        }    }}
[G, e, e, k, s, F, o, r, G, e, e, k, s]

Reference: https://docs.oracle.com/javase/9/docs/api/java/io/Reader.html#read–
Java-Functions
Java-IO package
Java-Reader
Java
Java
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