Java中的 MessageDigest getAlgorithm() 方法及示例

Java.security.MessageDigest类的getAlgorithm()方法用于返回与此消息摘要关联的算法的标准名称。

句法：

public final String getAlgorithm()

返回值：此方法返回消息摘要中使用的算法。

以下是说明getAlgorithm()方法的示例：

示例 1：

// Java program to demonstrate
// getAlgorithm() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
        try {
  
            // creating object of MessageDigest
            MessageDigest msd
                = MessageDigest.getInstance("MD5");
  
            // get the name of algorithm
            // used in MessageDigest
            // using getAlgorithm() method
            String algo = msd.getAlgorithm();
  
            // printing the string algo
            System.out.println("Algorithm : " + algo);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (ProviderException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

输出：

Algorithm : MD5

示例 2：

// Java program to demonstrate
// getAlgorithm() method
  
import java.security.*;
import java.util.*;
  
public class GFG1 {
    public static void main(String[] argv)
    {
        try {
            // creating object of MessageDigest
            MessageDigest msd
                = MessageDigest.getInstance("SHA-256");
  
            // get the name of algorithm used in MessageDigest
            // using getAlgorithm() method
            String algo = msd.getAlgorithm();
  
            // printing the string algo
            System.out.println("Algorithm : " + algo);
        }
  
        catch (NoSuchAlgorithmException e) {
  
            System.out.println("Exception thrown : " + e);
        }
        catch (ProviderException e) {
  
            System.out.println("Exception thrown : " + e);
        }
    }
}

输出：

Algorithm : SHA-256

参考： https://docs.oracle.com/javase/9/docs/api/ Java/security/MessageDigest.html#getAlgorithm–