The KeyPairGenerator class is used to generate pairs of public and private keys. Key pair generators are constructed using the

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getInstance

Key Generator Mac: 3. Generate DSA key pair: 4. KeyPair Generator For Public Key: 5. Wrap And Unwrap Key: 6. Generating a Public/Private Key Pair: 7. Generate a 576-bit DH key pair: 8. Generate a 1024-bit RSA key pair: 9. Getting the Bytes of a Generated Key Pair: 10. Get the bytes of the public and private keys. Oracle Java documentation is a little sparse on the topic, but it does look like with the SunJCE, a key generated asEC can be used with either ECDH or ECDSA. (I'm not an Elliptic curve expert, but) Theoretically, I believe that the domain parameters for ECDH and ECDSA have the same form, that is the equation of the curve and a base point G (CURVE, G). The key generation is called only one time for each android device, and for that reason the keys in each device should be different. Can anyone tell me what i am missing here? Java android key-pair key-generator. Public abstract class KeyPairGeneratorSpi extends Object. Disabled: no SafeJ information. This class defines the Service Provider Interface (SPI) for the KeyPairGenerator class, which is used to generate pairs of public and private keys. All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a key pair. Nov 01, 2018  The API we use to generate the key pairs is in the java.security package. That’s mean we have to import this package into our code. The class for generating the key pairs is KeyPairGenerator.To get an instance of this class we have to call the getInstance methods by providing two parameters. The first parameter is algorithm and the second parameter is the provider. KeyPairGenerator(String) Creates a KeyPairGenerator object for the specified algorithm. GenerateKeyPair Generates a key pair. GetAlgorithm Returns the standard name of the algorithm for this key generator. GetInstance(String) Generates a KeyPairGenerator object that implements the algorithm requested, as available in the environment.

factory methods (static methods that return instances of a given class).

A Key pair generator for a particular algorithm creates a public/private key pair that can be used with this algorithm. It also associates algorithm-specific parameters with each of the generated keys.

There are two ways to generate a key pair: in an algorithm-independent manner, and in an algorithm-specific manner. The only difference between the two is the initialization of the object:

• Algorithm-Independent Initialization

  All key pair generators share the concepts of a keysize and a source of randomness. The keysize is interpreted differently for different algorithms (e.g., in the case of the DSA algorithm, the keysize corresponds to the length of the modulus). There is an initialize method in this KeyPairGenerator class that takes these two universally shared types of arguments. There is also one that takes just a keysize argument, and uses the SecureRandom implementation of the highest-priority installed provider as the source of randomness. (If none of the installed providers supply an implementation of SecureRandom, a system-provided source of randomness is used.)

  Since no other parameters are specified when you call the above algorithm-independent initialize methods, it is up to the provider what to do about the algorithm-specific parameters (if any) to be associated with each of the keys.

  If the algorithm is the DSA algorithm, and the keysize (modulus size) is 512, 768, or 1024, then the Sun provider uses a set of precomputed values for the p, q, and g parameters. If the modulus size is not one of the above values, the Sun provider creates a new set of parameters. Other providers might have precomputed parameter sets for more than just the three modulus sizes mentioned above. Still others might not have a list of precomputed parameters at all and instead always create new parameter sets.

• Algorithm-Specific Initialization

  For situations where a set of algorithm-specific parameters already exists (e.g., so-called community parameters in DSA), there are two initialize methods that have an AlgorithmParameterSpec argument. One also has a SecureRandom argument, while the the other uses the SecureRandom implementation of the highest-priority installed provider as the source of randomness. (If none of the installed providers supply an implementation of SecureRandom, a system-provided source of randomness is used.)

In case the client does not explicitly initialize the KeyPairGenerator (via a call to an initialize method), each provider must supply (and document) a default initialization. For example, the Sun provider uses a default modulus size (keysize) of 1024 bits.

Note that this class is abstract and extends from KeyPairGeneratorSpi for historical reasons. Application developers should only take notice of the methods defined in this KeyPairGenerator class; all the methods in the superclass are intended for cryptographic service providers who wish to supply their own implementations of key pair generators.

Every implementation of the Java platform is required to support the following standard KeyPairGenerator algorithms and keysizes in parentheses:

• DiffieHellman (1024)
• DSA (1024)
• RSA (1024, 2048)

These algorithms are described in the KeyPairGenerator section of the Java Cryptography Architecture Standard Algorithm Name Documentation. Consult the release documentation for your implementation to see if any other algorithms are supported.

• Java Cryptography Tutorial

• Message Digest and MAC

• Keys and Key Store

• Generating Keys

• Digital Signature

• Cipher Text

• Java Cryptography Resources

• Selected Reading

Cryptography is the art and science of making a cryptosystem that is capable of providing information security.

Cryptography deals with the actual securing of digital data. It refers to the design of mechanisms based on mathematical algorithms that provide fundamental information security services. You can think of cryptography as the establishment of a large toolkit containing different techniques in security applications.

What is Cryptanalysis?

The art and science of breaking the cipher text is known as cryptanalysis.

Cryptanalysis is the sister branch of cryptography and they both co-exist. The cryptographic process results in the cipher text for transmission or storage. It involves the study of cryptographic mechanism with the intention to break them. Cryptanalysis is also used during the design of the new cryptographic techniques to test their security strengths.

Cryptography Primitives

Cryptography primitives are nothing but the tools and techniques in Cryptography that can be selectively used to provide a set of desired security services −

• Encryption
• Hash functions
• Message Authentication codes (MAC)
• Digital Signatures

Cryptography in Java

The Java Cryptography Architecture (JCA) is a set of API’s to implement concepts of modern cryptography such as digital signatures, message digests, certificates, encryption, key generation and management, and secure random number generation etc.

Using JCA developers can build their applications integrating security in them.

To integrate security in your applications rather than depending on the complicated security algorithms you can easily call the respective API’s provided in JCA for required services.

Hash functions are extremely useful and appear in almost all information security applications.

A hash function is a mathematical function that converts a numerical input value into another compressed numerical value. The input to the hash function is of arbitrary length but output is always of fixed length.

Values returned by a hash function are called message digest or simply hash values. The following picture illustrated hash function.

Java provides a class named MessageDigest which belongs to the package java.security. This class supports algorithms such as SHA-1, SHA 256, MD5 algorithms to convert an arbitrary length message to a message digest.

To convert a given message to a message digest, follow the steps given below −

Step 1: Create a MessageDigest object

The MessageDigest class provides a method named getInstance(). This method accepts a String variable specifying the name of the algorithm to be used and returns a MessageDigest object implementing the specified algorithm.

Create MessageDigest object using the getInstance() method as shown below.

Step 2: Pass data to the created MessageDigest object

After creating the message digest object, you need to pass the message/data to it. You can do so using the update() method of the MessageDigest class, this method accepts a byte array representing the message and adds/passes it to the above created MessageDigest object.

Step 3: Generate the message digest

You can generate the message digest using the digest() method od the MessageDigest class this method computes the hash function on the current object and returns the message digest in the form of byte array.

Generate the message digest using the digest method.

Example

Following is an example which reads data from a file and generate a message digest and prints it.

Output

The above program generates the following output −

MAC (Message Authentication Code) algorithm is a symmetric key cryptographic technique to provide message authentication. For establishing MAC process, the sender and receiver share a symmetric key K.

Essentially, a MAC is an encrypted checksum generated on the underlying message that is sent along with a message to ensure message authentication.

The process of using MAC for authentication is depicted in the following illustration −

In Java the Mac class of the javax.crypto package provides the functionality of message authentication code. Follow the steps given below to create message authentication code using this class.

Step 1: Create a KeyGenerator object

The KeyGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyGenerator object that generates secret keys.

Create KeyGenerator object using the getInstance() method as shown below.

Step 2: Create SecureRandom object

The SecureRandom class of the java.Security package provides a strong random number generator which is used to generate random numbers in Java. Instantiate this class as shown below.

Step 3: Initialize the KeyGenerator

The KeyGenerator class provides a method named init() this method accepts the SecureRandom object and initializes the current KeyGenerator.

Initialize the KeyGenerator object created in the previous step using this method.

Step 4: Generate key

Generate key using generateKey() method of the KeyGenerator class as shown below.

Step 5: Initialize the Mac object

The init() method of the Mac class accepts an Key object and initializes the current Mac object using the given key.

Step 6: Finish the mac operation

The doFinal() method of the Mac class is used to finish the Mac operation. Pass the required data in the form of byte array to this method and finsh the operation as shown below.

Example

The following example demonstrates the generation of Message Authentication Code (MAC) using JCA. Here, we take a simple message 'Hi how are you' and, generate a Mac for that message.

Output

The above program will generate the following output −

A cryptosystem is an implementation of cryptographic techniques and their accompanying infrastructure to provide information security services. A cryptosystem is also referred to as a cipher system.

The various components of a basic cryptosystem are Plaintext, Encryption Algorithm, Ciphertext, Decryption Algorithm, Encryption Key and, Decryption Key.

Where,

• Encryption Key is a value that is known to the sender. The sender inputs the encryption key into the encryption algorithm along with the plaintext in order to compute the cipher text.

• Decryption Key is a value that is known to the receiver. The decryption key is related to the encryption key, but is not always identical to it. The receiver inputs the decryption key into the decryption algorithm along with the cipher text in order to compute the plaintext.

Fundamentally there are two types of keys/cryptosystems based on the type of encryption-decryption algorithms.

Symmetric Key Encryption

The encryption process where same keys are used for encrypting and decrypting the information is known as Symmetric Key Encryption.

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The study of symmetric cryptosystems is referred to as symmetric cryptography. Symmetric cryptosystems are also sometimes referred to as secret key cryptosystems.

Following are a few common examples of symmetric key encryption −

• Digital Encryption Standard (DES)
• Triple-DES (3DES)
• IDEA
• BLOWFISH

Asymmetric Key Encryption

The encryption process where different keys are used for encrypting and decrypting the information is known as Asymmetric Key Encryption. Though the keys are different, they are mathematically related and hence, retrieving the plaintext by decrypting cipher text is feasible.

The Keys and certificates used/generated are stored in a data base called as keystore. By default this database is stored in a file named .keystore.

You can access the contents of this database using the KeyStore class of the java.security package. This manages three different entries namely, PrivateKeyEntry, SecretKeyEntry, TrustedCertificateEntry.

• PrivateKeyEntry
• SecretKeyEntry
• TrustedCertificateEntry

Storing a Key in keystore

In this section, we will learn how to store a key in a keystore. To store a key in the keystore, follow the steps given below.

Step 1: Create a KeyStore object

The getInstance() method of the KeyStore class of the java.security package accepts a string value representing the type of the keystore and returns a KeyStore object.

Create an object of the KeyStore class using the getInstance() method as shown below.

Step 2: Load the KeyStore object

The load() method of the KeyStore class accepts a FileInputStream object representing the keystore file and a String parameter specifying the password of the KeyStore.

In general, the KeyStore is stored in the file named cacerts, in the location C:/Program Files/Java/jre1.8.0_101/lib/security/ and its default password is changeit, load it using the load() method as shown below.

Step 3: Create the KeyStore.ProtectionParameter object

Instantiate the KeyStore.ProtectionParameter as shown below.

Step 4: Create a SecretKey object

Create the SecretKey (interface) object by instantiating its Sub class SecretKeySpec. While instantiating you need to pass password and algorithm as parameters to its constructor as shown below.

Step 5: Create a SecretKeyEntry object

Create an object of the SecretKeyEntry class by passing the SecretKey object created in the above step as shown below.

Step 6: Set an entry to the KeyStore

The setEntry() method of the KeyStore class accepts a String parameter representing the keystore entry alias, a SecretKeyEntry object, a ProtectionParameter object and, stores the entry under the given alias.

Set the entry to the keystore using the setEntry() method as shown below.

Example

The following example stores keys into the keystore existing in the “cacerts” file (windows 10 operating system).

Output

The above program generates the following output −

In this chapter, we will learn how to retrieve a key from the keystore using Java Cryptography.

To retrieve a key from the keystore, follow the steps given below.

Step 1: Create a KeyStore object

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The getInstance() method of the KeyStore class of the java.security package accepts a string value representing the type of the keystore and returns a KeyStore object.

Create an object of the KeyStore class using this method as shown below.

Step 2: Load the KeyStore object

The load() method of the KeyStore class accepts a FileInputStream object representing the keystore file and a String parameter specifying the password of the KeyStore.

In general, the KeyStore is stored in the file named cacerts, in the location C:/Program Files/Java/jre1.8.0_101/lib/security/ and its default password is changeit, load it using the load() method as shown below.

Step 3: Create the KeyStore.ProtectionParameter object

Instantiate the KeyStore.ProtectionParameter as shown below.

Step 4: Create a SecretKey object

Create the SecretKey (interface) object by instantiating its Sub class SecretKeySpec. While instantiating you need to pass password and algorithm as parameters to its constructor as shown below.

Step 5: Create a SecretKeyEntry object

Create an object of the SecretKeyEntry class by passing the SecretKey object created in the above step as shown below.

Step 6: set an entry to the KeyStore

The setEntry() method of the KeyStore class accepts a String parameter representing the keystore entry alias, a SecretKeyEntry object, a ProtectionParameter object and, stores the entry under the given alias.

Set the entry to the keystore using the setEntry() method as shown below.

Step 7: Create the KeyStore.SecretKeyEntry object

The getEntry() method of the KeyStore class accepts an alias (String parameter) and, an object of the ProtectionParameter class as parameters and returns a KeyStoreEntry object then you can cast this it into KeyStore.SecretKeyEntry object.

Create an object of the KeyStore.SecretKeyEntry class by passing the alias for required key and the protection parameter object created in the previous steps, to the getEntry() method as shown below.

Step 8: Create the key object of the retrieved entry

The getSecretKey() method of the SecretKeyEntry class returns a SecretKey object. Using this method create a SecretKey object as shown below.

Example

Following example shows how to retrieve keys from a key store. Here, we store a key in a keystore, which is in the “cacerts” file (windows 10 operating system), retrieve it, and display some of the properties of it such as the algorithm used to generate the key and, the format of the retrieved key.

Output

The above program generates the following output −

Java provides KeyGenerator class this class is used to generate secret keys and objects of this class are reusable.

To generate keys using the KeyGenerator class follow the steps given below.

Step 1: Create a KeyGenerator object

The KeyGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyGenerator object that generates secret keys.

Create KeyGenerator object using the getInstance() method as shown below.

Step 2: Create SecureRandom object

The SecureRandom class of the java.Security package provides a strong random number generator which is used to generate random numbers in Java. Instantiate this class as shown below.

Step 3: Initialize the KeyGenerator

The KeyGenerator class provides a method named init() this method accepts the SecureRandom object and initializes the current KeyGenerator.

Initialize the KeyGenerator object created in the previous step using the init() method.

Example

Following example demonstrates the key generation of the secret key using the KeyGenerator class of the javax.crypto package.

Output

The above program generates the following output −

Java provides the KeyPairGenerator class. This class is used to generate pairs of public and private keys. To generate keys using the KeyPairGenerator class, follow the steps given below.

Step 1: Create a KeyPairGenerator object

The KeyPairGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyPairGenerator object that generates keys.

Create KeyPairGenerator object using the getInstance() method as shown below.

Step 2: Initialize the KeyPairGenerator object

The KeyPairGenerator class provides a method named initialize() this method is used to initialize the key pair generator. This method accepts an integer value representing the key size.

Initialize the KeyPairGenerator object created in the previous step using this method as shown below.

Step 3: Generate the KeyPairGenerator

You can generate the KeyPair using the generateKeyPair() method of the KeyPairGenerator class. Generate the key pair using this method as shown below.

Step 4: Get the private key/public key

You can get the private key from the generated KeyPair object using the getPrivate() method as shown below.

You can get the public key from the generated KeyPair object using the getPublic() method as shown below.

Example

Following example demonstrates the key generation of the secret key using the KeyPairGenerator class of the javax.crypto package.

Output

The above program generates the following output −

Digital signatures allow us to verify the author, date and time of signatures, authenticate the message contents. It also includes authentication function for additional capabilities.

Advantages of digital signature

In this section, we will learn about the different reasons that call for the use of digital signature. There are several reasons to implement digital signatures to communications −

Authentication

Digital signatures help to authenticate the sources of messages. For example, if a bank’s branch office sends a message to central office, requesting for change in balance of an account. If the central office could not authenticate that message is sent from an authorized source, acting of such request could be a grave mistake.

Integrity

Once the message is signed, any change in the message would invalidate the signature.

Non-repudiation

By this property, any entity that has signed some information cannot at a later time deny having signed it.

Creating the digital signature

Let us now learn how to create a digital signature. You can create digital signature using Java following the steps given below.

Step 1: Create a KeyPairGenerator object

The KeyPairGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyPairGenerator object that generates keys.

Create KeyPairGenerator object using the getInstance() method as shown below.

Step 2: Initialize the KeyPairGenerator object

The KeyPairGenerator class provides a method named initialize() this method is used to initialize the key pair generator. This method accepts an integer value representing the key size.

Initialize the KeyPairGenerator object created in the previous step using the initialize() method as shown below.

Step 3: Generate the KeyPairGenerator

You can generate the KeyPair using the generateKeyPair() method. Generate the key pair using the generateKeyPair() method as shown below.

Step 4: Get the private key from the pair

You can get the private key from the generated KeyPair object using the getPrivate() method.

Get the private key using the getPrivate() method as shown below.

Step 5: Create a signature object

The getInstance() method of the Signature class accepts a string parameter representing required signature algorithm and returns the respective Signature object.

Create an object of the Signature class using the getInstance() method.

Step 6: Initialize the Signature object

The initSign() method of the Signature class accepts a PrivateKey object and initializes the current Signature object.

Initialize the Signature object created in the previous step using the initSign() method as shown below.

Step 7: Add data to the Signature object

The update() method of the Signature class accepts a byte array representing the data to be signed or verified and updates the current object with the data given.

Update the initialized Signature object by passing the data to be signed to the update() method in the form of byte array as shown below.

Step 8: Calculate the Signature

The sign() method of the Signature class returns the signature bytes of the updated data.

Calculate the Signature using the sign() method as shown below.

Example

Following Java program accepts a message from the user and generates a digital signature for the given message.

Output

The above program generates the following output −

You can create digital signature using Java and verify it following the steps given below.

Step 1: Create a KeyPairGenerator object

The KeyPairGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyPairGenerator object that generates keys.

Create KeyPairGenerator object using the getInstance() method as shown below.

Step 2: Initialize the KeyPairGenerator object

The KeyPairGenerator class provides a method named initialize() method. This method is used to initialize the key pair generator. This method accepts an integer value representing the key size.

Initialize the KeyPairGenerator object created in the previous step using the initialize() method as shown below.

Step 3: Generate the KeyPairGenerator

You can generate the KeyPair using the generateKeyPair() method. Generate the keypair using this method as shown below.

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Step 4: Get the private key from the pair

You can get the private key from the generated KeyPair object using the getPrivate() method.

Get the private key using the getPrivate() method as shown below.

Step 5: Create a signature object

The getInstance() method of the Signature class accepts a string parameter representing required signature algorithm and returns the respective Signature object.

Create an object of the Signature class using the getInstance() method.

Step 6: Initialize the Signature object

The initSign() method of the Signature class accepts a PrivateKey object and initializes the current Signature object.

Initialize the Signature object created in the previous step using the initSign() method as shown below.

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Step 7: Add data to the Signature object

The update() method of the Signature class accepts a byte array representing the data to be signed or verified and updates the current object with the data given.

Update the initialized Signature object by passing the data to be signed to the update() method in the form of byte array as shown below.

Step 8: Calculate the Signature

The sign() method of the Signature class returns the signature bytes of the updated data.

Calculate the Signature using the sign() method as shown below.

Step 9: Initialize the signature object for verification

To verify a Signature object you need to initialize it first using the initVerify() method it method accepts a PublicKey object.

Therefore, initialize the Signature object for verification using the initVerify() method as shown below.

Step 10: Update the data to be verified

Update the initialized (for verification) object with the data the data to be verified using the update method as shown below.

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Step 11: Verify the Signature

The verify() method of the Signature class accepts another signature object and verifies it with the current one. If a match occurs, it returns true else it returns false.

Verify the signature using this method as shown below.

Example

Following Java program accepts a message from the user, generates a digital signature for the given message, and verifies it.

Output

The above program generates the following output −

You can encrypt given data using the Cipher class of the javax.crypto package. Follow the steps given below to encrypt given data using Java.

Step 1: Create a KeyPairGenerator object

The KeyPairGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyPairGenerator object that generates keys.

Create KeyPairGenerator object using the getInstance() method as shown below. /cd-key-generator-for-pc-games-free-download.html.

Step 2: Initialize the KeyPairGenerator object

The KeyPairGenerator class provides a method named initialize() this method is used to initialize the key pair generator. This method accepts an integer value representing the key size.

Initialize the KeyPairGenerator object created in the previous step using the initialize() method as shown below.

Step 3: Generate the KeyPairGenerator

You can generate the KeyPair using the generateKeyPair() method of the KeyPairGenerator class. Generate the key pair using this method as shown below.

Step 4: Get the public key

You can get the public key from the generated KeyPair object using the getPublic() method as shown below.

Get the public key using this method as shown below.

Step 5: Create a Cipher object

The getInstance() method of Cipher class accepts a String variable representing the required transformation and returns a Cipher object that implements the given transformation.

Create the Cipher object using the getInstance() method as shown below.

Step 6: Initialize the Cipher object

The init() method of the Cipher class accepts two parameters an integer parameter representing the operation mode (encrypt/decrypt) and, a Key object representing the public key.

Initialize the Cypher object using the init() method as shown below.

Step 7: Add data to the Cipher object

The update() method of the Cipher class accepts a byte array representing the data to be encrypted and updates the current object with the data given.

Update the initialized Cipher object by passing the data to the update() method in the form of byte array as shown below.

Step 8: Encrypt the data

The doFinal() method of the Cipher class completes the encryption operation. Therefore, finish the encryption using this method as shown below.

Example

Following Java program accepts text from user, encrypts it using RSA algorithm and, prints the encrypted format of the given text.

Output

The above program generates the following output −

You can decrypt the encrypted data using the Cipher class of the javax.crypto package. Follow the steps given below to decrypt given data using Java.

Step 1: Create a KeyPairGenerator object

The KeyPairGenerator class provides getInstance() method which accepts a String variable representing the required key-generating algorithm and returns a KeyPairGenerator object that generates keys.

Create KeyPairGenerator object using the getInstance() method as shown below.

Step 2: Initialize the KeyPairGenerator object

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The KeyPairGenerator class provides a method named initialize() this method is used to initialize the key pair generator. This method accepts an integer value representing the key size.

Initialize the KeyPairGenerator object created in the previous step using the initialize() method as shown below.

Step 3: Generate the KeyPairGenerator

You can generate the KeyPair using the generateKeyPair() method of the KeyPairGenerator class. Generate the key pair using this method as shown below.

Step 4: Get the public key

You can get the public key from the generated KeyPair object using the getPublic() method as shown below.

Step 5: Create a Cipher object

The getInstance() method of Cipher class accepts a String variable representing the required transformation and returns a Cipher object that implements the given transformation.

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Create the Cipher object using the getInstance() method as shown below.

Step 6: Initialize the Cipher object

The init() method of the Cipher class accepts two parameters

• An integer parameter representing the operation mode (encrypt/decrypt)
• Key object representing the public key

Initialize the Cypher object using the init() method as shown below.

Step 7: Add data to the Cipher object

The update() method of the Cipher class accepts a byte array representing the data to be encrypted and updates the current object with the data given.

Update the initialized Cipher object by passing the data to the update() method in the form of byte array as shown below.

Step 8: Encrypt the data

The doFinal() method of the Cipher class completes the encryption operation. Therefore, finish the encryption using this method as shown below.

Step 9: Initialize the Cipher object for decryption

To decrypt the cypher encrypted in the previous steps you need to initialize it for decryption.

Therefore, initialize the cipher object by passing the parameters Cipher.DECRYPT_MODE and PrivateKey object as shown below.

Step 10: Decrypt the data

Finally, Decrypt the encrypted text using the doFinal() method as shown below.

Example

Following Java program accepts text from user, encrypts it using RSA algorithm and, prints the cipher of the given text, decrypts the cipher and prints the decrypted text again.

Output

The above program generates the following output −