- Java.io package classes
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- Java.io - BufferedInputStream
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- Java.io - File
- Java.io - FileDescriptor
- Java.io - FileInputStream
- Java.io - FileOutputStream
- Java.io - FilePermission
- Java.io - FileReader
- Java.io - FileWriter
- Java.io - FilterInputStream
- Java.io - FilterOutputStream
- Java.io - FilterReader
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- Java.io - InputStream
- Java.io - InputStreamReader
- Java.io - LineNumberInputStream
- Java.io - LineNumberReader
- Java.io - ObjectInputStream
- Java.io - ObjectInputStream.GetField
- Java.io - ObjectOutputStream
- io - ObjectOutputStream.PutField
- Java.io - ObjectStreamClass
- Java.io - ObjectStreamField
- Java.io - OutputStream
- Java.io - OutputStreamWriter
- Java.io - PipedInputStream
- Java.io - PipedOutputStream
- Java.io - PipedReader
- Java.io - PipedWriter
- Java.io - PrintStream
- Java.io - PrintWriter
- Java.io - PushbackInputStream
- Java.io - PushbackReader
- Java.io - RandomAccessFile
- Java.io - Reader
- Java.io - SequenceInputStream
- Java.io - SerializablePermission
- Java.io - StreamTokenizer
- Java.io - StringBufferInputStream
- Java.io - StringReader
- Java.io - StringWriter
- Java.io - Writer
- Java.io package extras
- Java.io - Interfaces
- Java.io - Exceptions
- Java.io package Useful Resources
- Java.io - Discussion
Java.io.InputStream.read() Method
Description
The java.io.InputStream.read(byte[] b) method reads b.length number of bytes from the input stream to the buffer array b. The bytes read is returned as integer.
Declaration
Following is the declaration for java.io.InputStream.read(byte[] b) method −
public int read(byte[] b)
Parameters
b − The destination byte array.
Return Value
The method returns the number of bytes actually read into the buffer, or -1 if the end of the stream is reached.
Exception
IOException − If an I/O error occurs.
NullPointerException − If b is null.
Example
The following example shows the usage of java.io.InputStream.read(byte[] b) method.
package com.tutorialspoint; import java.io.FileInputStream; import java.io.InputStream; public class InputStreamDemo { public static void main(String[] args) throws Exception { InputStream is = null; byte[] buffer = new byte[5]; char c; try { // new input stream created is = new FileInputStream("C://test.txt"); System.out.println("Characters printed:"); // read stream data into buffer is.read(buffer); // for each byte in the buffer for(byte b:buffer) { // convert byte to character c = (char)b; // prints character System.out.print(c); } } catch(Exception e) { // if any I/O error occurs e.printStackTrace(); } finally { // releases system resources associated with this stream if(is!=null) is.close(); } } }
Assuming we have a text file c:/test.txt, which has the following content. This file will be used as an input for our example program −
ABCDE
Let us compile and run the above program, this will produce the following result −
Characters printed: ABCDE