Modifying ConverterBean

The source code for the original ConverterBean class was modified to add the if..else clause that tests whether the caller is in the role of TutorialUser. . If the user is in the correct role, the currency conversion is computed and displayed. If the user is not in the correct role, the computation is not performed, and the application displays the result as 0. The code example can be found in the following file:

tut-install/examples/ejb/converter-secure/converter-secure-ejb/src/java/
converter/ejb/ConverterBean.java

The code snippet (with modifications shown in bold) is as follows:

package converter.ejb;

import java.math.BigDecimal;
import javax.ejb.Stateless;
import java.security.Principal;
import javax.annotation.Resource;
import javax.ejb.SessionContext;
import javax.annotation.security.DeclareRoles;
import javax.annotation.security.RolesAllowed;

@Stateless()
@DeclareRoles("TutorialUser")
public class ConverterBean{

    @Resource SessionContext ctx;
    private BigDecimal yenRate = new BigDecimal("89.5094");
    private BigDecimal euroRate = new BigDecimal("0.0081");

    @RolesAllowed("TutorialUser")
     public BigDecimal dollarToYen(BigDecimal dollars) {
        BigDecimal result = new BigDecimal("0.0");
        Principal callerPrincipal = ctx.getCallerPrincipal();
        if (ctx.isCallerInRole("TutorialUser")) {
            result = dollars.multiply(yenRate);
            return result.setScale(2, BigDecimal.ROUND_UP);
        } else {
            return result.setScale(2, BigDecimal.ROUND_UP);
        }
    }

    @RolesAllowed("TutorialUser")
    public BigDecimal yenToEuro(BigDecimal yen) {
        BigDecimal result = new BigDecimal("0.0");
        Principal callerPrincipal = ctx.getCallerPrincipal();
        if (ctx.isCallerInRole("TutorialUser")) {
             result = yen.multiply(euroRate);
             return result.setScale(2, BigDecimal.ROUND_UP);
        } else {
             return result.setScale(2, BigDecimal.ROUND_UP);
        }
    }
}