* This is an abstract class that defines the methods common to all * {@code CertPath}s. Subclasses can handle different kinds of * certificates (X.509, PGP, etc.). *
* All {@code CertPath} objects have a type, a list of * {@code Certificate}s, and one or more supported encodings. Because the * {@code CertPath} class is immutable, a {@code CertPath} cannot * change in any externally visible way after being constructed. This * stipulation applies to all public fields and methods of this class and any * added or overridden by subclasses. *
* The type is a {@code String} that identifies the type of * {@code Certificate}s in the certification path. For each * certificate {@code cert} in a certification path {@code certPath}, * {@code cert.getType().equals(certPath.getType())} must be * {@code true}. *
* The list of {@code Certificate}s is an ordered {@code List} of * zero or more {@code Certificate}s. This {@code List} and all * of the {@code Certificate}s contained in it must be immutable. *
* Each {@code CertPath} object must support one or more encodings * so that the object can be translated into a byte array for storage or * transmission to other parties. Preferably, these encodings should be * well-documented standards (such as PKCS#7). One of the encodings supported * by a {@code CertPath} is considered the default encoding. This * encoding is used if no encoding is explicitly requested (for the * {@link #getEncoded() getEncoded()} method, for instance). *
* All {@code CertPath} objects are also {@code Serializable}. * {@code CertPath} objects are resolved into an alternate * {@link CertPathRep CertPathRep} object during serialization. This allows * a {@code CertPath} object to be serialized into an equivalent * representation regardless of its underlying implementation. *
* {@code CertPath} objects can be created with a * {@code CertificateFactory} or they can be returned by other classes, * such as a {@code CertPathBuilder}. *
* By convention, X.509 {@code CertPath}s (consisting of * {@code X509Certificate}s), are ordered starting with the target * certificate and ending with a certificate issued by the trust anchor. That * is, the issuer of one certificate is the subject of the following one. The * certificate representing the {@link TrustAnchor TrustAnchor} should not be * included in the certification path. Unvalidated X.509 {@code CertPath}s * may not follow these conventions. PKIX {@code CertPathValidator}s will * detect any departure from these conventions that cause the certification * path to be invalid and throw a {@code CertPathValidatorException}. * *
Every implementation of the Java platform is required to support the * following standard {@code CertPath} encodings: *
* Concurrent Access *
* All {@code CertPath} objects must be thread-safe. That is, multiple * threads may concurrently invoke the methods defined in this class on a * single {@code CertPath} object (or more than one) with no * ill effects. This is also true for the {@code List} returned by * {@code CertPath.getCertificates}. *
* Requiring {@code CertPath} objects to be immutable and thread-safe * allows them to be passed around to various pieces of code without worrying * about coordinating access. Providing this thread-safety is * generally not difficult, since the {@code CertPath} and * {@code List} objects in question are immutable. * * @see CertificateFactory * @see CertPathBuilder * * @author Yassir Elley * @since 1.4 */ public abstract class CertPath implements Serializable { private static final long serialVersionUID = 6068470306649138683L; private String type; // the type of certificates in this chain /** * Creates a {@code CertPath} of the specified type. *
* This constructor is protected because most users should use a
* {@code CertificateFactory} to create {@code CertPath}s.
*
* @param type the standard name of the type of
* {@code Certificate}s in this path
*/
protected CertPath(String type) {
this.type = type;
}
/**
* Returns the type of {@code Certificate}s in this certification
* path. This is the same string that would be returned by
* {@link java.security.cert.Certificate#getType() cert.getType()}
* for all {@code Certificate}s in the certification path.
*
* @return the type of {@code Certificate}s in this certification
* path (never null)
*/
public String getType() {
return type;
}
/**
* Returns an iteration of the encodings supported by this certification
* path, with the default encoding first. Attempts to modify the returned
* {@code Iterator} via its {@code remove} method result in an
* {@code UnsupportedOperationException}.
*
* @return an {@code Iterator} over the names of the supported
* encodings (as Strings)
*/
public abstract Iterator
* This algorithm is implemented by this method. If it is overridden,
* the behavior specified here must be maintained.
*
* @param other the object to test for equality with this certification path
* @return true if the specified object is equal to this certification path,
* false otherwise
*/
public boolean equals(Object other) {
if (this == other)
return true;
if (! (other instanceof CertPath))
return false;
CertPath otherCP = (CertPath) other;
if (! otherCP.getType().equals(type))
return false;
List thisCertList = this.getCertificates();
List otherCertList = otherCP.getCertificates();
return(thisCertList.equals(otherCertList));
}
/**
* Returns the hashcode for this certification path. The hash code of
* a certification path is defined to be the result of the following
* calculation:
* {@code
* hashCode = path.getType().hashCode();
* hashCode = 31*hashCode + path.getCertificates().hashCode();
* }
* This ensures that {@code path1.equals(path2)} implies that
* {@code path1.hashCode()==path2.hashCode()} for any two certification
* paths, {@code path1} and {@code path2}, as required by the
* general contract of {@code Object.hashCode}.
*
* @return the hashcode value for this certification path
*/
public int hashCode() {
int hashCode = type.hashCode();
hashCode = 31*hashCode + getCertificates().hashCode();
return hashCode;
}
/**
* Returns a string representation of this certification path.
* This calls the {@code toString} method on each of the
* {@code Certificate}s in the path.
*
* @return a string representation of this certification path
*/
public String toString() {
StringBuffer sb = new StringBuffer();
Iterator stringIterator =
getCertificates().iterator();
sb.append("\n" + type + " Cert Path: length = "
+ getCertificates().size() + ".\n");
sb.append("[\n");
int i = 1;
while (stringIterator.hasNext()) {
sb.append("=========================================="
+ "===============Certificate " + i + " start.\n");
Certificate stringCert = stringIterator.next();
sb.append(stringCert.toString());
sb.append("\n========================================"
+ "=================Certificate " + i + " end.\n\n\n");
i++;
}
sb.append("\n]");
return sb.toString();
}
/**
* Returns the encoded form of this certification path, using the default
* encoding.
*
* @return the encoded bytes
* @exception CertificateEncodingException if an encoding error occurs
*/
public abstract byte[] getEncoded()
throws CertificateEncodingException;
/**
* Returns the encoded form of this certification path, using the
* specified encoding.
*
* @param encoding the name of the encoding to use
* @return the encoded bytes
* @exception CertificateEncodingException if an encoding error occurs or
* the encoding requested is not supported
*/
public abstract byte[] getEncoded(String encoding)
throws CertificateEncodingException;
/**
* Returns the list of certificates in this certification path.
* The {@code List} returned must be immutable and thread-safe.
*
* @return an immutable {@code List} of {@code Certificate}s
* (may be empty, but not null)
*/
public abstract List getCertificates();
/**
* Replaces the {@code CertPath} to be serialized with a
* {@code CertPathRep} object.
*
* @return the {@code CertPathRep} to be serialized
*
* @throws ObjectStreamException if a {@code CertPathRep} object
* representing this certification path could not be created
*/
protected Object writeReplace() throws ObjectStreamException {
try {
return new CertPathRep(type, getEncoded());
} catch (CertificateException ce) {
NotSerializableException nse =
new NotSerializableException
("java.security.cert.CertPath: " + type);
nse.initCause(ce);
throw nse;
}
}
/**
* Alternate {@code CertPath} class for serialization.
* @since 1.4
*/
protected static class CertPathRep implements Serializable {
private static final long serialVersionUID = 3015633072427920915L;
/** The Certificate type */
private String type;
/** The encoded form of the cert path */
private byte[] data;
/**
* Creates a {@code CertPathRep} with the specified
* type and encoded form of a certification path.
*
* @param type the standard name of a {@code CertPath} type
* @param data the encoded form of the certification path
*/
protected CertPathRep(String type, byte[] data) {
this.type = type;
this.data = data;
}
/**
* Returns a {@code CertPath} constructed from the type and data.
*
* @return the resolved {@code CertPath} object
*
* @throws ObjectStreamException if a {@code CertPath} could not
* be constructed
*/
protected Object readResolve() throws ObjectStreamException {
try {
CertificateFactory cf = CertificateFactory.getInstance(type);
return cf.generateCertPath(new ByteArrayInputStream(data));
} catch (CertificateException ce) {
NotSerializableException nse =
new NotSerializableException
("java.security.cert.CertPath: " + type);
nse.initCause(ce);
throw nse;
}
}
}
}