Reading specific llines from a file each one representing a different data type and variable in Java

Question

I've been researching on the web how to go about this and what class is best to use for file parsing ect.

I've been programming In java for awhile now and parsing files and writing to them has always been one of weakest points literally I just don't understand It.

Specifically I have a file named

jihoon.txt

its contents are this

username = ji
password = kim106
id = 0

i want to store ji into a string variable, and kim106 into a string variable and id into an int variable while disregarding "username = " ect. Could someone please help thanks in advance :).

Can you guarantee that the file will always have these items and in this order? If not then really I would be considering saving them as name value pairs. — ThePerson, Mar 01 '13 at 20:30
Take a look at one of the many configuration file libraries out there. Apache Commons Java Configuration -> http://commons.apache.org/proper/commons-configuration/ is a fine piece. — , Mar 01 '13 at 20:31

score 1 · Answer 1 · edited Jun 20 '20 at 09:12

A good way would be to use the file as a Property. This way you can load everything the way you want.

You would load you file as such :

properties.load(new FileInputStream("path/jihoon.txt"));

Then you can access your data as such :

String value = properties.getProperty(key);

Knowing what the key is for your values you can have something like this (according to your example in the question) :

int id = Integer.parseInt(properties.getProperty("id")).intValue();
String username = properties.getProperty("username");
String password = properties.getProperty("password");

Then this way you don't have to worry about the order of your file.

Why would you prefer a `HashMap` over a `Property`? Especially the fact that it's coming from a file. Wouldn't this just be creating your version of the `Property`? – blo0p3r Mar 01 '13 at 20:41
1

A better excercise for the poster of the question, if he's bad at I/O. – Has QUIT--Anony-Mousse Mar 01 '13 at 20:42
Love it! I'll agree with you on this. – blo0p3r Mar 01 '13 at 20:48

score -1 · Answer 3 · answered Mar 01 '13 at 20:31

-1

A properties file would be best for these kinds of operations

Example

answered Mar 01 '13 at 20:31

Justin Jasmann

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Reading specific llines from a file each one representing a different data type and variable in Java

3 Answers3

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