java.util.scanner - Java Scanner won't read -

i'm trying read file has information written in format: somename:adoublenumber , returns name , double. i've written following scanner, doesn't work, ideas why?

scanner readfile = new scanner("text.txt"); readfile.usedelimiter(":"); while (filescanner.hasnext()) { string name = readfile.next(); } 

you're not reading file. you're reading string "text.txt". need file first.

    scanner readfile = new scanner(new file("text.txt")); // don't forget catch filenotfoundexception!     readfile.usedelimiter(":|\\n");     while (filescanner.hasnext()) {        string name = readfile.next();        double value = readfile.nextdouble();        system.out.println(name + " " + value);     } 

i took code comment , formatted, , this

public class myproject {      class fileinput {          scanner readfile = new scanner(new file("text.txt")); // don't forget catch filenotfoundexception!          readfile.usedelimiter(":|\\n");          while (filescanner.hasnext()) {              string name = readfile.next();              double value = readfile.nextdouble();              system.out.println(name + " " + value);          }      } } 

now seem have problem - perhaps meant class fileinput public void fileinput() throws exception? when this, compiles. need main() method run it! add this:

public static void main(string[] args) throws exception {     myproject proj = new myproject();     proj.fileinput(); } 

now when ran got error. means there problem in code gave begin with. of course, code never intended copy/pasted, more give idea of capability. anyway, error is:

exception in thread "main" java.util.inputmismatchexception     @ java.util.scanner.throwfor(scanner.java:840)     @ java.util.scanner.next(scanner.java:1461)     @ java.util.scanner.nextdouble(scanner.java:2387)     @ myproject.fileinput(myproject.java:9) <--- happened in our code     @ myproject.main(myproject.java:16) 

the line happened on parsedouble. so, instead, let's try doing different way. can double raw piece of text, , parse actual double this:

    while (readfile.hasnext()) {          string name = readfile.next();          string valuestr = readfile.next();         double value = double.parsedouble(valuestr);          system.out.println(name + " " + value);      }  

so whole completed program is:

import java.util.*; import java.io.*; public class myproject {      public void fileinput() throws exception {          scanner readfile = new scanner(new file("text.txt")); // don't forget catch filenotfoundexception!          readfile.usedelimiter(":|\\n");          while (readfile.hasnext()) {              string name = readfile.next();              string valuestr = readfile.next();             double value = double.parsedouble(valuestr);              system.out.println("name: " + name);             system.out.println("value: " + value);             system.out.println(""); // blank line         }      }      public static void main(string[] args) throws exception {         myproject proj = new myproject();         proj.fileinput();     } 

so input file text being:

this:1234.5 that:321.0 other:0.122 

the output was

c:\documents , settings\glowcoder\my documents>java myproject name: value: 1234.5  name: value: 321.0  name: other value: 0.122   c:\documents , settings\glowcoder\my documents>java myproject }