Find centralized, trusted content and collaborate around the technologies you use most. Connect and share knowledge within a single location that is structured and easy to search. I have text files that all need to be read in these 4 for loops. The other 2 for loops are for drawing a square of 16X16 pixels. I want it to read all the numbers 1 by 1 and store it into an int array because the char array is not doing the trick.
You're reading the text file as a character array so you're getting the ASCII character values of the numbers when you read it them as ints e. You should parse each integer character from the line in the text file. Doesn't your text file only have one row of numbers? Your scanner is trying to read more lines, and why turn them to an array of characters?!?! A character can only be a number think about seperating your 3 digit numbers with spaces and using a StringTokenizer or something of the sort.
How are we doing? Please help us improve Stack Overflow. Take our short survey. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? So when we call. Now the Scanner is at the beginning of the second line in our file, and when we try to call. BufferedReader reads text from a character-input stream, but it does so by buffering characters in order to provide efficient.
Since accessing an HDD is a very time-consuming operation, BufferedReader gathers more data than we ask for, and stores it in a buffer. The idea is that when we call. In case we wanted to read it, we'd read it directly from the buffer instead of from the disk, which is much more efficient.
This brings us to what BufferedReader is good for - reading large files. BufferedReader has a significantly larger buffer memory than Scanner characters by default vs characters by default, respectively. BufferedReader is used as a wrapper for other Readers , and so constructors for BufferedReader take a Reader object as a parameter, such as a FileReader.
We're using try-with-resources so we don't have to close the reader manually:. It's advised to wrap a FileReader with a BufferedReader , exactly due to the performance benefits. What these two classes help us accomplish is to store an object or array of objects into a file, and then easily read from that file. This can only be done with classes that implement the Serializable interface.
The Serializable interface has no methods or fields and serves only to identify the semantics of being serializable:. Though, keep in mind that this approach, just like Files. The code above doesn't do anything special, and we'd rarely use streams this way. However, since we're loading this data into an ArrayList so that we can process it in the first place - streams provide an excellent way of doing this.
It doesn't matter if this is all you do in main but in a bigger applicaiton it might become an issue. May you please explain to me more in detail on what you mean by this, I am fairly new to Java programming.
Edited and added example. Paul Samsotha Paul Samsotha k 33 33 gold badges silver badges bronze badges. Ankit Rustagi Ankit Rustagi 5, 11 11 gold badges 36 36 silver badges 65 65 bronze badges.
Yes was an assumption, i would usually store the content in one single array. Yes count would store the number of lines read. That would be pretty obvious, i keep count so that it would help in for loops in future if the need be.
Elipzer Elipzer 6 6 silver badges 21 21 bronze badges. I use this method: import java. Scanner; import java. Ayakashi Ayakashi 11 1 1 bronze badge. Why do you use Scanner to read file in a pre-splitted way just to join parts and split them again? What's the reason to add such answer to 3-years old question without any new good ideas? Please also note that there are other "bad smells" in your code.
Why scn is a static member instead of just local variable? What happens if there was FileNotFoundException? Hint: NullPointerException. Not closing Scanner is also not a good idea if this snippet would be used in a bigger application. Sign up or log in Sign up using Google. Sign up using Facebook.
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