Reading Strings from lines in Java

Question

I have a txt file formatted like:

Name 'Paul' 9-years old

How can I get from a "readline":

String the_name="Paul"

and

int the_age=9

in Java, discarding all the rest?

I have:

  ...       
    BufferedReader bufferedReader = new BufferedReader(fileReader);
    StringBuffer stringBuffer = new StringBuffer();
    String line;
    while ((line = bufferedReader.readLine()) != null) {

       //put the name value in the_name

       //put age value in the_age

    }
...

Please suggest, thanks.

Answer 1

As you're using BufferedReader and everything is on the one line, you would have to split it to extract the data. Some additional formatting is then required to remove the quotes & extract the year part of age. No need for any fancy regex:

String[] strings = line.split(" ");
if (strings.length >= 3) {
   String the_name= strings[1].replace("'", "");
   String the_age = strings[2].substring(0, strings[2].indexOf("-"));
}

I notice you have this functionality in a while loop. For this to work, make sure that every line keeps the format:

text 'Name' digit-any other text
    ^^    ^^     ^

Important chars are

• Spaces: min of 3 tokens needed for split array
• Single quotes
• - Hyphen character

Answer 2

use java.util.regex.Pattern:

Pattern pattern = Pattern.compile("Name '(.*)' (\d*)-years old");
for (String line : lines) {
    Matcher matcher = pattern.matcher(line);
    if (matcher.matches()) {
        String theName = matcher.group(1);
        int theAge = Integer.parseInt(matcher.group(2));
    }
}

Answer 3

You can use the String.substring , String.indexOf , String.lastIndexOf , and Integer.parseInt methods as follows:

String line = "Name 'Paul' 9-years old";
String theName = line.substring(line.indexOf("'") + 1, line.lastIndexOf("'"));
String ageStr = line.substring(line.lastIndexOf("' ") + 2, line.indexOf("-years"));
int theAge = Integer.parseInt(ageStr);
System.out.println(theName + " " + theAge);

Output:

Paul 9