CODEWITHSUNDEEP
javaandroidarraysbyteaddition
omaflak
omaflak

Reputation: 175

List<byte[]> fills wrong

In this code when the loop is finished the array is filled with the same value everywhere. After some debugging I noticed that at every add() the array is filled up entirely with the same value. 

List<byte[]> datas = new ArrayList<byte[]>();

// CODE ... //

FileInputStream fis = new FileInputStream(file);
byte[] buff = new byte[2];
int n;
while((n=fis.read(buff))!=-1){
     this.datas.add(buff);
}
fis.close();

I tried the same code with an array of String and it worked correctly...

Why is this happening, and how can I fix it?

Upvotes: 0

Views: 83

Answers (1)

JML
JML

Reputation: 721

You're filling the ArrayList with the same instance of the byte[] buff variable. So each time you modify buff (in fis.read(buff) ) you're actually modifying all the items in the ArrayList.

Try creating a new byte[] in each iteartion:

List<byte[]> datas = new ArrayList<byte[]>();

// CODE ... //

FileInputStream fis = new FileInputStream(file);
byte[] buff = new byte[2];
int n
while((n=fis.read(buff))!=-1){
    this.datas.add(buff);
    buff = new byte[2];
}
fis.close();

Upvotes: 1

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