How to convert InputStream to byte array in Java

0 votes
How do I read an entire InputStream into a byte array?

Thanxx in advanced!!
Apr 9, 2020 in Java by kartik
• 37,520 points
9,957 views

2 answers to this question.

0 votes

Hello @kartik,

You need to read each byte from your InputStream and write it to a ByteArrayOutputStream. 

You can then retrieve the underlying byte array by calling toByteArray(); e.g.  

InputStream is = ...
ByteArrayOutputStream buffer = new ByteArrayOutputStream();

int nRead;
byte[] data = new byte[16384];

while ((nRead = is.read(data, 0, data.length)) != -1) {
  buffer.write(data, 0, nRead);
}

return buffer.toByteArray();

Thank you!!

answered Apr 9, 2020 by Niroj
• 82,760 points
0 votes

The class IOUtils, lib: https://mvnrepository.com/artifact/commons-io/commons-io/2.8.0,  can help you.

answered Sep 23, 2020 by Anthony

Related Questions In Java

0 votes
2 answers

How to convert array into list in Java?

Another workaround if you use apache commons-lang: int[] ...READ MORE

answered Aug 9, 2018 in Java by samarth295
• 2,220 points
208 views
0 votes
3 answers

How to convert File to Byte[] in Java?

import java.io.File; import java.nio.file.Files; File file; // ...(file is initialised)... byte[] ...READ MORE

answered Aug 14, 2018 in Java by samarth295
• 2,220 points
931 views
+1 vote
3 answers

How to convert a List to an Array in Java?

Either: Foo[] array = list.toArray(new Foo[list.size()]); or: Foo[] array = ...READ MORE

answered Aug 7, 2018 in Java by Akrati
• 3,170 points
257 views
0 votes
2 answers

How can I convert byte array into hex string in Java?

public static String byteArrayToHex(byte[] a) { ...READ MORE

answered Aug 29, 2019 in Java by Sirajul
• 59,070 points
1,652 views
0 votes
1 answer

What are the prerequisites to learn Hadoop in java perspective?

In my day job, I've just spent ...READ MORE

answered Oct 11, 2018 in Big Data Hadoop by Frankie
• 9,810 points
236 views
0 votes
1 answer

How is inheritance in C++ different than that in Java?

The purpose of inheritance is same for ...READ MORE

answered Feb 6, 2019 in Java by Priyaj
• 58,120 points
199 views
0 votes
1 answer

What is the reason for no ConcurrentHashSet against ConcurrentHashMap?

Hello, There's no built in type for ConcurrentHashSet because you ...READ MORE

answered Apr 8, 2020 in Java by Niroj
• 82,760 points
151 views
0 votes
1 answer

How to pass an object from one activity to another on Android?

Hello @kartik, Implement your class with Serializable. Let's ...READ MORE

answered Apr 8, 2020 in Java by Niroj
• 82,760 points
154 views
0 votes
1 answer

How do I convert a String to an int in Java?

Hello @kartik, We can use the parseInt(String str) method of ...READ MORE

answered Jul 28, 2020 in Java by Niroj
• 82,760 points
185 views
0 votes
1 answer

how to do global variable declaration in java

Hello,​ Global varriable which is defined after the ...READ MORE

answered Apr 3, 2020 in Java by Niroj
• 82,760 points
138 views