Class KeyGenerator

java.lang.Object

cloud.opencode.base.crypto.key.KeyGenerator

public final class KeyGenerator
extends Object

Key generator utility for symmetric and asymmetric keys - Generate cryptographic keys 密钥生成器工具类 - 生成对称和非对称密钥

Features | 主要功能:

• AES, RSA, EC, Ed25519 key generation - AES、RSA、EC、Ed25519 密钥生成

Usage Examples | 使用示例:

SecretKey aesKey = KeyGenerator.generateAesKey(256);
KeyPair rsaKeyPair = KeyGenerator.generateRsaKeyPair(2048);

Security | 安全性:

• Thread-safe: Yes - 线程安全: 是
• Null-safe: Yes - 空值安全: 是

Since:

JDK 25, opencode-base-crypto V1.0.0

Author:

Leon Soo www.LeonSoo.com

See Also:

• OpenCode.cloud

Method Summary

Modifier and Type	Method	Description
static String	exportKeyPairPem(KeyPair keyPair)	Export key pair to PEM format 导出密钥对为 PEM 格式
static byte[]	exportPrivateKey(PrivateKey privateKey)	Export private key to byte array 导出私钥为字节数组
static String	exportPrivateKeyPem(PrivateKey privateKey)	Export private key to PEM format 导出私钥为 PEM 格式
static byte[]	exportPublicKey(PublicKey publicKey)	Export public key to byte array 导出公钥为字节数组
static String	exportPublicKeyPem(PublicKey publicKey)	Export public key to PEM format 导出公钥为 PEM 格式
static SecretKey	generateAes128Key()	Generate AES-128 key 生成 AES-128 密钥
static SecretKey	generateAes256Key()	Generate AES-256 key 生成 AES-256 密钥
static SecretKey	generateAesKey(int keyBits)	Generate AES key with specified key size 生成指定大小的 AES 密钥
static SecretKey	generateChacha20Key()	Generate ChaCha20 key 生成 ChaCha20 密钥
static KeyPair	generateEcKeyPair(CurveType curve)	Generate elliptic curve key pair 生成椭圆曲线密钥对
static KeyPair	generateEd25519KeyPair()	Generate Ed25519 key pair for EdDSA signatures 生成用于 EdDSA 签名的 Ed25519 密钥对
static KeyPair	generateEd448KeyPair()	Generate Ed448 key pair for EdDSA signatures 生成用于 EdDSA 签名的 Ed448 密钥对
static KeyPair	generateP256KeyPair()	Generate P-256 elliptic curve key pair 生成 P-256 椭圆曲线密钥对
static KeyPair	generateP384KeyPair()	Generate P-384 elliptic curve key pair 生成 P-384 椭圆曲线密钥对
static KeyPair	generateRsa2048KeyPair()	Generate RSA-2048 key pair 生成 RSA-2048 密钥对
static KeyPair	generateRsa4096KeyPair()	Generate RSA-4096 key pair 生成 RSA-4096 密钥对
static KeyPair	generateRsaKeyPair(int keyBits)	Generate RSA key pair with specified key size 生成指定大小的 RSA 密钥对
static KeyPair	generateSm2KeyPair()	Generate SM2 key pair (Chinese standard) 生成 SM2 密钥对（中国标准）
static SecretKey	generateSm4Key()	Generate SM4 key (Chinese standard) 生成 SM4 密钥（中国标准）
static KeyPair	generateX25519KeyPair()	Generate X25519 key pair for key exchange 生成用于密钥交换的 X25519 密钥对
static PublicKey	importCertificatePublicKey(String input)	Import a public key from an X.509 certificate (PEM or bare Base64).
static KeyPair	importKeyPairPem(String publicKeyPem, String privateKeyPem)	Import key pair from PEM format 从 PEM 格式导入密钥对
static PrivateKey	importPrivateKey(byte[] encoded, String algorithm)	Import private key from byte array 从字节数组导入私钥
static PrivateKey	importPrivateKeyFlexible(String input)	Import a private key from either PEM-with-markers or bare Base64.
static PrivateKey	importPrivateKeyPem(String pem)	Import private key from PEM format 从 PEM 格式导入私钥
static PublicKey	importPublicKey(byte[] encoded, String algorithm)	Import public key from byte array 从字节数组导入公钥
static PublicKey	importPublicKeyFlexible(String input)	Import a public key from either PEM-with-markers or bare Base64.
static PublicKey	importPublicKeyPem(String pem)	Import public key from PEM format 从 PEM 格式导入公钥
static SecretKey	secretKey(byte[] keyBytes, String algorithm)	Create secret key from byte array 从字节数组创建对称密钥

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

generateAesKey

public static SecretKey generateAesKey(int keyBits)

Generate AES key with specified key size 生成指定大小的 AES 密钥

Parameters:

keyBits - key size in bits (128, 192, or 256)

Returns:

generated AES secret key

Throws:

OpenKeyException - if key generation fails

generateAes128Key

public static SecretKey generateAes128Key()

Generate AES-128 key 生成 AES-128 密钥

Returns:

generated AES-128 secret key

Throws:

OpenKeyException - if key generation fails

generateAes256Key

public static SecretKey generateAes256Key()

Generate AES-256 key 生成 AES-256 密钥

Returns:

generated AES-256 secret key

Throws:

OpenKeyException - if key generation fails

generateChacha20Key

public static SecretKey generateChacha20Key()

Generate ChaCha20 key 生成 ChaCha20 密钥

Returns:

generated ChaCha20 secret key

Throws:

OpenKeyException - if key generation fails

generateSm4Key

public static SecretKey generateSm4Key()

Generate SM4 key (Chinese standard) 生成 SM4 密钥（中国标准）

Returns:

generated SM4 secret key

Throws:

OpenKeyException - if key generation fails

secretKey

public static SecretKey secretKey(byte[] keyBytes,
 String algorithm)

Create secret key from byte array 从字节数组创建对称密钥

Parameters:

keyBytes - key bytes

algorithm - algorithm name (e.g., "AES", "ChaCha20")

Returns:

secret key

Throws:

OpenKeyException - if key creation fails

generateRsaKeyPair

public static KeyPair generateRsaKeyPair(int keyBits)

Generate RSA key pair with specified key size 生成指定大小的 RSA 密钥对

Parameters:

keyBits - key size in bits (minimum 2048 recommended)

Returns:

generated RSA key pair

Throws:

OpenKeyException - if key generation fails

generateRsa2048KeyPair

public static KeyPair generateRsa2048KeyPair()

Generate RSA-2048 key pair 生成 RSA-2048 密钥对

Returns:

generated RSA-2048 key pair

Throws:

OpenKeyException - if key generation fails

generateRsa4096KeyPair

public static KeyPair generateRsa4096KeyPair()

Generate RSA-4096 key pair 生成 RSA-4096 密钥对

Returns:

generated RSA-4096 key pair

Throws:

OpenKeyException - if key generation fails

generateEcKeyPair

public static KeyPair generateEcKeyPair(CurveType curve)

Generate elliptic curve key pair 生成椭圆曲线密钥对

Parameters:

curve - elliptic curve type

Returns:

generated EC key pair

Throws:

OpenKeyException - if key generation fails

generateP256KeyPair

public static KeyPair generateP256KeyPair()

Generate P-256 elliptic curve key pair 生成 P-256 椭圆曲线密钥对

Returns:

generated P-256 key pair

Throws:

OpenKeyException - if key generation fails

generateP384KeyPair

public static KeyPair generateP384KeyPair()

Generate P-384 elliptic curve key pair 生成 P-384 椭圆曲线密钥对

Returns:

generated P-384 key pair

Throws:

OpenKeyException - if key generation fails

generateEd25519KeyPair

public static KeyPair generateEd25519KeyPair()

Generate Ed25519 key pair for EdDSA signatures 生成用于 EdDSA 签名的 Ed25519 密钥对

Returns:

generated Ed25519 key pair

Throws:

OpenKeyException - if key generation fails

generateEd448KeyPair

public static KeyPair generateEd448KeyPair()

Generate Ed448 key pair for EdDSA signatures 生成用于 EdDSA 签名的 Ed448 密钥对

Returns:

generated Ed448 key pair

Throws:

OpenKeyException - if key generation fails

generateX25519KeyPair

public static KeyPair generateX25519KeyPair()

Generate X25519 key pair for key exchange 生成用于密钥交换的 X25519 密钥对

Returns:

generated X25519 key pair

Throws:

OpenKeyException - if key generation fails

generateSm2KeyPair

public static KeyPair generateSm2KeyPair()

Generate SM2 key pair (Chinese standard) 生成 SM2 密钥对（中国标准）

Returns:

generated SM2 key pair

Throws:

OpenKeyException - if key generation fails

exportPublicKey

public static byte[] exportPublicKey(PublicKey publicKey)

Export public key to byte array 导出公钥为字节数组

Parameters:

publicKey - public key to export

Returns:

encoded public key bytes

Throws:

OpenKeyException - if export fails

exportPrivateKey

public static byte[] exportPrivateKey(PrivateKey privateKey)

Export private key to byte array 导出私钥为字节数组

Parameters:

privateKey - private key to export

Returns:

encoded private key bytes

Throws:

OpenKeyException - if export fails

exportPublicKeyPem

public static String exportPublicKeyPem(PublicKey publicKey)

Export public key to PEM format 导出公钥为 PEM 格式

Parameters:

publicKey - public key to export

Returns:

PEM formatted public key

Throws:

OpenKeyException - if export fails

exportPrivateKeyPem

public static String exportPrivateKeyPem(PrivateKey privateKey)

Export private key to PEM format 导出私钥为 PEM 格式

Parameters:

privateKey - private key to export

Returns:

PEM formatted private key

Throws:

OpenKeyException - if export fails

exportKeyPairPem

public static String exportKeyPairPem(KeyPair keyPair)

Export key pair to PEM format 导出密钥对为 PEM 格式

Parameters:

keyPair - key pair to export

Returns:

PEM formatted key pair (public key + private key)

Throws:

OpenKeyException - if export fails

importPublicKey

public static PublicKey importPublicKey(byte[] encoded,
 String algorithm)

Import public key from byte array 从字节数组导入公钥

Parameters:

encoded - encoded public key bytes

algorithm - key algorithm (e.g., "RSA", "EC")

Returns:

imported public key

Throws:

OpenKeyException - if import fails

importPrivateKey

public static PrivateKey importPrivateKey(byte[] encoded,
 String algorithm)

Import private key from byte array 从字节数组导入私钥

Parameters:

encoded - encoded private key bytes

algorithm - key algorithm (e.g., "RSA", "EC")

Returns:

imported private key

Throws:

OpenKeyException - if import fails

importPublicKeyPem

public static PublicKey importPublicKeyPem(String pem)

Import public key from PEM format 从 PEM 格式导入公钥

Parameters:

pem - PEM formatted public key

Returns:

imported public key

Throws:

OpenKeyException - if import fails

importPrivateKeyPem

public static PrivateKey importPrivateKeyPem(String pem)

Import private key from PEM format 从 PEM 格式导入私钥

Parameters:

pem - PEM formatted private key

Returns:

imported private key

Throws:

OpenKeyException - if import fails

importKeyPairPem

public static KeyPair importKeyPairPem(String publicKeyPem,
 String privateKeyPem)

Import key pair from PEM format 从 PEM 格式导入密钥对

Parameters:

publicKeyPem - PEM formatted public key

privateKeyPem - PEM formatted private key

Returns:

imported key pair

Throws:

OpenKeyException - if import fails

importPublicKeyFlexible

public static PublicKey importPublicKeyFlexible(String input)

Import a public key from either PEM-with-markers or bare Base64. 从 PEM 格式或裸 Base64 导入公钥。

Accepts both -----BEGIN PUBLIC KEY-----... and raw Base64-encoded X.509 SubjectPublicKeyInfo bytes. The algorithm is auto-detected.

同时接受带 PEM 标记和裸 Base64 编码的 X.509 SubjectPublicKeyInfo 字节， 自动检测算法。

Parameters:

input - PEM or bare Base64 encoded public key | PEM 或裸 Base64 编码的公钥

Returns:

imported public key | 导入的公钥

Throws:

OpenKeyException - if import fails

Since:

V1.0.4

importPrivateKeyFlexible

public static PrivateKey importPrivateKeyFlexible(String input)

Import a private key from either PEM-with-markers or bare Base64. 从 PEM 格式或裸 Base64 导入私钥。

Accepts both -----BEGIN PRIVATE KEY-----... and raw Base64-encoded PKCS#8 bytes. The algorithm is auto-detected. This is particularly useful for payment platforms (e.g. WeChat Pay) that ship merchant private keys as bare PKCS#8 Base64 blobs without PEM markers.

同时接受带 PEM 标记和裸 Base64 编码的 PKCS#8 字节，自动检测算法。 特别适用于以裸 PKCS#8 Base64 格式分发商户私钥的支付平台（如微信支付）。

Parameters:

input - PEM or bare Base64 encoded private key | PEM 或裸 Base64 编码的私钥

Returns:

imported private key | 导入的私钥

Throws:

OpenKeyException - if import fails

Since:

V1.0.4

importCertificatePublicKey

public static PublicKey importCertificatePublicKey(String input)

Import a public key from an X.509 certificate (PEM or bare Base64). 从 X.509 证书（PEM 或裸 Base64）导入公钥。

Decodes the input, constructs an X509Certificate via CertificateFactory, and extracts the public key. Accepts both -----BEGIN CERTIFICATE-----... and raw Base64-encoded DER bytes.

解码输入，通过 CertificateFactory 构造 X509Certificate 并提取公钥。同时接受带 PEM 标记和裸 Base64 编码的 DER 字节。

Parameters:

input - PEM or bare Base64 encoded X.509 certificate | PEM 或裸 Base64 编码的 X.509 证书

Returns:

the certificate's public key | 证书公钥

Throws:

OpenKeyException - if parsing fails

Since:

V1.0.4