JDK (Java Development Kit) Tutorials
Dr. Herong Yang, Version 5.00

java.security.cert.Certificate - The Certificate Class

This section describes the certificate class: java.security.cert.Certificate, which represents a signed certificate of a public key.

In the previous chapter, I learned that the "keytool" command line tool can be used to manage certificates stored in "keystore" files. Now I want to learn how to use java.security.cert.Certificate and java.security.KeyStore classes to manage certificates stored in "keystore" files.

java.security.cert.Certificate is an abstract class representing common features of different implementations of different certificate types. Its main methods are:

  • getEncoded() - Returns a byte array of the encoded form of this certificate. The encoding format used depends on the certificate type. For "X.509" type of certificates, the encoding format will be "ASN.1 DER".
  • getPublicKey() - Returns the public key of signed in this certificate.
  • getType() - Returns the type of this certificate.
  • verify() - Verifies this certificate with the specified public key. I am not sure why this method has no return value.

In JDK, there is a deprecated interface named as Certificate under a different package, java.security.Certificate. To help the compiler to take the correct class definition, I think I should use the full class name, java.security.cert.Certificate, in my Java programs.

Last update: 2006.

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 Downloading and Installing JDK 1.3.1 on Windows

 Downloading and Installing JDK 1.4.1 on Windows

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 Downloading and Installing JDK 1.6.2 on Windows

 Date, Time and Calendar Classes

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 DOM (Document Object Model) - API for XML Files

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 DTD (Document Type Definition) - XML Validation

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 XSL (Extensible Stylesheet Language)

 Message Digest Algorithm Implementations in JDK

 Private key and Public Key Pair Generation

 PKCS#8/X.509 Private/Public Encoding Standards

 Digital Signature Algorithm and Sample Program

 "keytool" Commands and "keystore" Files

KeyStore and Certificate Classes

java.security.cert.Certificate - The Certificate Class

 Using CertificateFactory Class to Read in Certificates

 Reading and Writing Certificates in DER and RFC Formats

 java.security.KeyStore - The 'keystore' Class

 JcaKeyStoreTest.java - 'keystore' Class Test Program

 Secret Key Generation and Management

 Cipher - Secret Key Encryption and Decryption

 The SSL (Secure Socket Layer) Protocol

 SSL Socket Communication Testing Programs

 SSL Client Authentication

 HTTPS (Hypertext Transfer Protocol Secure)

 References

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Dr. Herong Yang, updated in 2008
java.security.cert.Certificate - The Certificate Class