JavaInputStream和OutputStream的区别

流可以定义为数据的序列或连续的数据流。流是处理输入/输出的一种清晰方式。流有两种类型，如下所示：

在上图中，我们的 InputStream 和 OutputStream 将驻留在 Byte Stream 中。那么让我们来讨论字节流。

1. Byte Stream： Byte Stream 提供了一种方便的方式来处理字节的输入和输出。字节流被进一步划分为各种类，但最顶层的类如下所示：

1.1 InputStream： InputStream是Byte Stream的抽象类，描述流输入，用于读取，可以是文件、图片、音频、视频、网页等，无所谓。因此， InputStream 一次从源读取一项数据。

1.2 OutputStream： OutputStream是Byte Stream的抽象类，描述流输出，用于向文件、图像、音频等写入数据，因此OutputStream一次向目的地写入数据。

InputStream 和 OutputStream 的区别

InputStream	OutputStream
1. It is an abstract class that describes Stream Input.	1. It is an abstract class that describes Stream Output.
2. InputStream Read data from the source once at a time.	2. OutputStream Write Data to the destination once at a time.
3. InputStream consist of method which performs: Read next byte of data from the input stream and return -1 at the end of the file: public abstract int read()throws IOException Close current InputStream: public int available()throws IOException Returns an estimate of the number of bytes that can be read from the current input stream: public void close()throws IOException	3. Output Stream consists of methods which perform: Write a byte to current Outputstream : public void write(int)throws IOException Write array of byte to current output stream : public void write(byte[])throws IOException Flushes the current OutputStream: public void flush()throws IOException Close  current Output Stream. : public void close()throws IOException
4. Types of InputStream are: FileInputStream ByteArrayInputStream FilterInputStream ObjectInputStream In these types the most important and mostly used type is FileInputStream.	4. Types of OutputStream are: FileOutputStream ByteArrayOutputStream FilterOutputStream ObjectOutputStream In these types the most important and mostly used type is FileOutput Stream.

InputStream 的程序：

在本程序中，文件 gfg.txt 由“GEEKSFORGEEKS”组成。

注意：在文件保存在Java程序保存的同一位置然后按照下面的程序。如果文件保存在某个特定位置，则写入详细信息，例如。

FileInputStream fileIn=new FileInputStream("C:\\gfg.txt"); 

Java

// Imported to use methods
import java.io.FileInputStream;
  
// Main Class
public class InputStreamExample {
    public static void main(String args[])
    {
        // Reading from Source file
        try {
            FileInputStream fileIn
                = new FileInputStream("gfg.txt");
            int i = 0;
            while ((i = fileIn.read()) != -1) {
                System.out.print((char)i);
            }
            fileIn.close();
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出：

GEEKSFORGEEKS 

输出流程序

这里 gfg.txt 文件是空的，并且保存在Java Program 的保存位置。该程序将 GeeksforGeeks 写入空文件，如果文本成功写入文件，则显示消息“文件已成功更新”。

Java

// Imported to use inbuilt methods
import java.io.FileOutputStream;
  
// Main class
public class OutputStreamExample {
    public static void main(String args[])
    {
        // Writing in file gfg.txt
        try {
            FileOutputStream fileOut
                = new FileOutputStream("gfg.txt");
            String s = "GeeksforGeeks";
  
            // converting string into byte array
            byte b[] = s.getBytes();
            fileOut.write(b);
            fileOut.close();
            System.out.println(
                "file is successfully updated!!");
        }
        catch (Exception e) {
            System.out.println(e);
        }
    }
}

输出：

file is successfully updated!!

当我们再次使用第一个程序读取文件时，输出如下所示：

GeeksforGeeks