error cannot access class com.opensymphony.xwork2.ActionContext, wrong version

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1

Error(1,32): cannot access class com.opensymphony.xwork2.ActionContext; class file has wrong version 49.0, should be 45.3 or 46.0 or 47.0 or 48.0

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import java.util.Map;

public class loginAction extends ActionSupport 
{
private String userId;
  private String password;
  public String execute() throws Exception{

    if ("admin".equals(userId) && "admin".equals(password)) {
      Map session = ActionContext.getContext().getSession();
      session.put("logged-in","true");
            return SUCCESS;
        }
    else{
       return ERROR;
    }
    }

    public String logout() throws Exception {

    Map session = ActionContext.getContext().getSession();
    session.remove("logged-in");
        return SUCCESS;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    public String getUserId() {
        return userId;
    }

    public void setUserId(String userId) {
        this.userId = userId;
    }
}
2

which version of java are you using?
it sounds like you need version 1.5 or higher.