How to filter string in java

With this Code-Snippet:

String abc = "nama=john; class=6; height=170; weight=70";
for(String sa : abc.split(";")){
    System.out.println(sa.trim());
}

you generate this output:

nama=john
class=6
height=170
weight=70

if you want to add a specific String into a list you put the sa.trim() at the List.add parameter. To find the height-String you can use: if(sa.trim().startsWith("height")) and you have the needed String.

you can use this regex:

(?<=height=)(\d+)(?=;|\Z)

if you want to implement this, you can do it like this:

Pattern pattern = Pattern.compile("(?<=height=)(\\d+)(?=;|\\Z)");

// create matcher object.
Matcher m = pattern.matcher(abc);

if (m.find()) 
{
    String height =  m.group(0);
} 
else 
{
    System.out.println("not found");
}

here, you have an example: https://regex101.com/r/iM3gY0/2
and here you have an executable snipped: https://ideone.com/azngNt

If you want all parameter, you can use this regex:

(\w+)=([\d|\w]+)(?=;|\"|\Z)

so you get as Pattern:

Pattern pattern = Pattern.compile("(\\w+)=([\d|\\w]+)(?=;|\\"|\\Z)");

and the Regex101 again: https://regex101.com/r/uT6uK1/3

@Fast Snail you are correct, but I think they wanted an integer value of it:

final String string = "nama=john; class=6; height=170; weight=70";
final String[] tokens = string.split("; ");

for (String token : tokens) {
    if (token.contains("height")) {
        System.out.println(token);
        final String[] heightSplit = token.split("=");
        Integer heightValue = new Integer(heightSplit[1]);
        System.out.println("height=" + heightValue);
    }
}

System.out.println(tokens.length);

This should do what you need.

Use String tokenizer

import java.util.StringTokenizer;


public class stringval {



    StringTokenizer st = new StringTokenizer(" nama=john, class=6, height=170, weight=70;",",");{

while(st.hasMoreTokens()){

        String abc=st.nextToken();
        if(abc.equals("height=170")){
            StringTokenizer s=new StringTokenizer(abc,"=");
            while(s.hasMoreTokens()){
            String str=s.nextToken();
            if (s.equals("170")){
                System.out.print(s);
                break;
            }


            }
     }
}

    }
}

With Java 8 you can do the following:

Map<String, String> map = Arrays.stream("nama=john; class=6; height=170; weight=70".split(";"))
            .map(s -> s.trim().split("="))
            .collect(Collectors.toMap(s -> s[0], s -> s[1]));

System.out.println(map.get("height")); //170

Thanks Mr. MrT.

Code answer: Resolved.

String abc = "nama=john; class=6; height=170; weight=70";
String[] tokens = abc.split("; ");
        List<String> listString = new ArrayList<String>();
        String mod = new String();

        for(String s:tokens){
            mod =s;
            System.out.println(s);
            listString.add(mod);
        }

        System.out.println(listString.size());

for(String abcd :listString){
            if(abcd.trim().startsWith("height")){
                System.out.println(abcd);
            }
        }