java - 通过算法显示所有 JAC 安全提供商及其服务类型

Question

我想创建一个简单的java代码来显示所有安全提供者:

• 姓名
• 信息
• 服务类型
• 算法

主Activity.java

import java.io.ObjectInputStream.GetField;
import java.security.Provider;
import java.security.Provider.Service;
import java.security.Security;

public class MainActivity {
    public static void main(String[] args) {

        System.out.println("Availble Providers are:");
        Provider[] providerList = Security.getProviders();
        for (int i = 0; i < providerList.length; i++) {
            System.out.println("[" + (i + 1) + "] - Name: "
                    + providerList[i].getName());

            System.out.println("Information:\n" + providerList[i].getInfo());

            System.out
                    .print("Here are all providers with types of service and algorithm provided:\n");

        }
        
        for (int i = 0; i < serviceList.length; i++) {
            System.out.println("- Name: " + providerList[i].getName() + "\n");
            System.out.print("Service Type: " + serviceList[i].getType()
                    + "Algorithm: " + serviceList[i].getAlgorithm());

        }
    }
}

在第二个 for 循环之前，我需要初始化服务以便能够调用服务类型和算法。

Answer 1

您需要将第二个循环置于第一个循环内，因为您需要当前提供程序，以便可以调用其 getServices 方法。像这样的东西:

import java.security.Provider;
import java.security.Provider.Service;
import java.security.Security;
import java.util.Set;

public class MainActivity
{
  public static void main(String[] args)
  {
    Provider [] providerList = Security.getProviders();
    for (Provider provider : providerList)
     {
       System.out.println("Name: "  + provider.getName());
       System.out.println("Information:\n" + provider.getInfo());

       Set<Service> serviceList = provider.getServices();
       for (Service service : serviceList)
        {
          System.out.println("Service Type: " + service.getType() + " Algorithm " + service.getAlgorithm());
        }
     }
  }
}