Java KeyStore getKey()用法及代碼示例

java.security.KeyStore類的getKey()方法用於獲取與給定別名關聯的 key ，並使用給定密碼進行恢複。

用法:

public final Key getKey(String alias, char[] password)
    throws KeyStoreException, 
           NoSuchAlgorithmException, 
           UnrecoverableKeyException

參數：此方法接受以下參數：

alias:這是用來檢查 key 的別名
password:這是用於恢複要檢查的 key 的密碼

返回值：此方法返回所請求別名的 key (如果存在)。

異常：此方法引發以下異常

KeyStoreException：如果未加載 key 庫。
NoSuchAlgorithmException：如果缺少算法

注意：由於不存在“ privatekey” key 庫，因此本文中的所有程序都無法在在線IDE上運行。您可以在係統上的Java編譯器上檢查此代碼。要檢查此代碼，請在係統上創建 key 庫“ privatekey”，並設置自己的 key 庫密碼以訪問該 key 庫。

下麵是說明getKey()方法的示例：

示例1:

// Java program to demonstrate getKey() method 
  
import java.security.*; 
import java.security.cert.*; 
import java.util.*; 
import java.io.*; 
  
public class GFG { 
    public static void main(String[] argv) 
    { 
        try { 
  
            // creating the object of KeyStore 
            // and getting instance 
            // By using getInstance() method 
            KeyStore sr = KeyStore.getInstance("JKS"); 
  
            // keystore password is required to access keystore 
            char[] pass = ("123456").toCharArray(); 
  
            // creating and initializing object of InputStream 
            InputStream is 
                = new FileInputStream( 
                    "f:/java/private key.store"); 
  
            // initializing keystore object 
            sr.load(is, pass); 
  
            // getting the Key 
            // using getKey() method 
            Key key = sr.getKey("ftpkey", pass); 
  
            // display the result 
            System.out.println("Key : "
                               + key); 
        } 
  
        catch (NoSuchAlgorithmException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (NullPointerException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (KeyStoreException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (FileNotFoundException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (IOException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (CertificateException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (UnrecoverableKeyException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
    } 
}

輸出：

示例2:對於KeyStoreException

// Java program to demonstrate getKey() method 
  
import java.security.*; 
import java.security.cert.*; 
import java.util.*; 
import java.io.*; 
  
public class GFG { 
    public static void main(String[] argv) 
    { 
        try { 
  
            // creating the object of KeyStore 
            // and getting instance 
            // By using getInstance() method 
            KeyStore sr = KeyStore.getInstance("JKS"); 
  
            // keystore password is required to access keystore 
            char[] pass = ("123456").toCharArray(); 
  
            // creating and initializing object of InputStream 
            InputStream is 
                = new FileInputStream( 
                    "f:/java/private key.store"); 
  
            // initializing keystore object 
            // sr.load(is, pass); 
  
            // getting the Key 
            // using getKey() method 
            Key key = sr.getKey("ftpkey", pass); 
  
            // display the result 
            System.out.println("Key : "
                               + key); 
        } 
        catch (FileNotFoundException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (NullPointerException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (KeyStoreException e) { 
  
            System.out.println("\nException thrown : " + e); 
        } 
        catch (UnrecoverableKeyException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
        catch (NoSuchAlgorithmException e) { 
  
            System.out.println("Exception thrown : " + e); 
        } 
    } 
}

輸出：

參考： https://docs.oracle.com/javase/9/docs/api/java/security/KeyStore.html#getKey-java.lang.String-char:A-

相關用法

注：本文由純淨天空篩選整理自RohitPrasad3大神的英文原創作品 KeyStore getKey() method in Java with Examples。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。