BearerTokenInterceptor.java

package access.manage;

import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpRequest;
import org.springframework.http.client.ClientHttpRequestExecution;
import org.springframework.http.client.ClientHttpRequestInterceptor;
import org.springframework.http.client.ClientHttpResponse;

import java.io.IOException;

public class BearerTokenInterceptor implements ClientHttpRequestInterceptor {

    private final String bearerToken;

    public BearerTokenInterceptor(String bearerToken) {
        this.bearerToken = String.format("Bearer %s", bearerToken);
    }

    @Override
    public ClientHttpResponse intercept(
            HttpRequest request, byte[] body, ClientHttpRequestExecution execution) throws IOException {

        HttpHeaders headers = request.getHeaders();
        if (!headers.containsKey(HttpHeaders.AUTHORIZATION)) {
            headers.set(HttpHeaders.AUTHORIZATION, bearerToken);
        }
        return execution.execute(request, body);
    }

}