Java Programming Tutorial - 81 - Reading from Files

How to read data from a file

Category:

People & Blogs

Tags:

• install
• download
• jdk
• se
• ee
• java
• development
• kit
• new
• beginner
• tutorials
• eclipse
• variables
• if
• while
• loop
• object
• classes

[nWANTED]

Another way to get file contents:

while (x.hasNextLine()) System.out.println(x.nextLine(­));

[ojstrike]

great tutorial as expected. wondering if you're covering vectors also... but i think its all GUI from here

[dropbows90]

I hear crickets in the background. Are you programming in the woods? Right on!

[nitricdx]

can you use this same method to read a Config file?

[raheelbutt92]

How can I open a file that i have created with Formatter to store more values???

[lNUMPUN]

My error (see my comment below) only occurs when I have only 1 number, 1 first name, and 1 last name. When I added more numbers and names to my file, it printed out the correct stuff.

[lNUMPUN]

I'm getting an error involving my readFile method:

Exception in thread "main" java.util.NoSuchElementExcepti­on at java.util.Scanner.throwFor(Unk­nown Source) at java.util.Scanner.next(Unknown Source) at readfile.readFile(readfile.jav­a:24) --> This line is the declaration of c. at apples.main(apples.java:5) --> This line calls the method readFile.

[gatoo23]

@Tinzert

int sum=0;

while(x.hasNextInt){

sum+=x.nextInt();

}

[QuantumSicarius]

@Tinzert Store it in a variable and then convert it to a int, make temp variables to add them!

[Genuigr]

My program NEVER writes, what's in the class. I tried many things but nothings working. can so help?

[Tinzert]

Say I read a number from a file -- how would I add those numbers together? I saved the read data as int variables but for some reason I get an error "unexpected type" when they should be treated as regular variables.

[ShwariDeveloper]

@nWANTED yes this is far better compared to hasNext() because you read the whole line it is not confusing is it like wen u print the whole line, println but i think hasNext() is good to cover first in tutorial. java must be having many methods to read a file i guess.