Code Recipes Blog

In this post under JJWT, I will show with example how to parse a simple unsecured JSON Web Token containing claims as payload.

Below is the complete main code for your reference

Main class

1  package defaultPackage;
2  import io.jsonwebtoken.Claims;
3  import io.jsonwebtoken.Header;
4  import io.jsonwebtoken.Jwt;
5  import io.jsonwebtoken.JwtParser;
6  import io.jsonwebtoken.JwtParserBuilder;
7  import io.jsonwebtoken.Jwts;
8  
9  public class Example2 {
10     public static void main(String[] args) {
11         JwtParserBuilder jwtParserBuilder = Jwts.parser();
12         jwtParserBuilder.unsecured();
13         JwtParser jwtParser = jwtParserBuilder.build();
14         Jwt<Header, Claims> jwt = jwtParser.parseUnsecuredClaims("eyJ0eXAiOiJKV1QiLCJhbGciOiJub25lIn0.eyJzdWIiOiIxMjM0NTY3ODkwIiwiaWF0IjoxNjYxNjU5OTU1LCJuYW1lIjoiU3VtYW50aCJ9.");
15         System.out.println(jwt.getHeader());
16         System.out.println(jwt.getPayload());       
17     }
18 }

In the above code, at line 11, I create an instance of “JwtParserBuilder” class by name “jwtParserBuilder”

At line 12, I am telling the “jwtParserBuilder” instance that it has to parse unsecured JWT by calling “unsecured” method on the builder instance.

At line 13, I build the parser by calling “build” method on the builder instance.

At line 14, I parse the unsecured JWT by calling “parseUnsecuredClaims” method on the “JwtParser” instance.

At line 15, I print the header and at line 16 I print the payload.

In this way we can parse an unsecured JWT.

Output

{typ=JWT, alg=none}
{sub=1234567890, iat=1661659955, name=Sumanth}