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| author | Mark Wielaard <mark@gcc.gnu.org> | 2006-03-10 21:46:48 +0000 |
|---|---|---|
| committer | Mark Wielaard <mark@gcc.gnu.org> | 2006-03-10 21:46:48 +0000 |
| commit | 8aa540d2f783474d1d2e06f16744bf67b9c1facc (patch) | |
| tree | ea38c56431c5d4528fb54254c3f8e50f517bede3 /libjava/classpath/java/security/MessageDigest.java | |
| parent | 27079765d00123f8e53d0e1ef7f9d46559266e6d (diff) | |
| download | gcc-8aa540d2f783474d1d2e06f16744bf67b9c1facc.zip gcc-8aa540d2f783474d1d2e06f16744bf67b9c1facc.tar.gz gcc-8aa540d2f783474d1d2e06f16744bf67b9c1facc.tar.bz2 | |
Imported GNU Classpath 0.90
Imported GNU Classpath 0.90
* scripts/makemake.tcl: Set gnu/java/awt/peer/swing to ignore.
* gnu/classpath/jdwp/VMFrame.java (SIZE): New constant.
* java/lang/VMCompiler.java: Use gnu.java.security.hash.MD5.
* java/lang/Math.java: New override file.
* java/lang/Character.java: Merged from Classpath.
(start, end): Now 'int's.
(canonicalName): New field.
(CANONICAL_NAME, NO_SPACES_NAME, CONSTANT_NAME): New constants.
(UnicodeBlock): Added argument.
(of): New overload.
(forName): New method.
Updated unicode blocks.
(sets): Updated.
* sources.am: Regenerated.
* Makefile.in: Likewise.
From-SVN: r111942
Diffstat (limited to 'libjava/classpath/java/security/MessageDigest.java')
| -rw-r--r-- | libjava/classpath/java/security/MessageDigest.java | 257 |
1 files changed, 102 insertions, 155 deletions
diff --git a/libjava/classpath/java/security/MessageDigest.java b/libjava/classpath/java/security/MessageDigest.java index 8a6af64..b817759 100644 --- a/libjava/classpath/java/security/MessageDigest.java +++ b/libjava/classpath/java/security/MessageDigest.java @@ -40,54 +40,10 @@ package java.security; import gnu.java.security.Engine; /** - * <p>This <code>MessageDigest</code> class provides applications the - * functionality of a message digest algorithm, such as <i>MD5</i> or <i>SHA</i>. * Message digests are secure one-way hash functions that take arbitrary-sized - * data and output a fixed-length hash value.</p> - * - * <p>A <code>MessageDigest</code> object starts out initialized. The data is - * processed through it using the <code>update()</code> methods. At any point - * <code>reset()</code> can be called to reset the digest. Once all the data to - * be updated has been updated, one of the <code>digest()</code> methods should - * be called to complete the hash computation.</p> - * - * <p>The <code>digest()</code> method can be called <b>once</b> for a given - * number of updates. After <code>digest()</code> has been called, the - * <code>MessageDigest</code> object is <b>reset</b> to its initialized state. - * </p> - * - * <p>Implementations are free to implement the {@link Cloneable} interface. - * Client applications can test cloneability by attempting cloning and catching - * the {@link CloneNotSupportedException}: - * - * <pre> - * MessageDigest md = MessageDigest.getInstance("SHA"); - * try - * { - * md.update(toChapter1); - * MessageDigest tc1 = md.clone(); - * byte[] toChapter1Digest = tc1.digest(); - * md.update(toChapter2); - * // ... - * } - * catch (CloneNotSupportedException x) - * { - * throw new DigestException("couldn't make digest of partial content"); - * } - * </pre> - * - * <p>Note that if a given implementation is not cloneable, it is still possible - * to compute intermediate digests by instantiating several instances, if the - * number of digests is known in advance.</p> - * - * <p>Note that this class is abstract and extends from {@link MessageDigestSpi} - * for historical reasons. Application developers should only take notice of the - * methods defined in this <code>MessageDigest</code> class; all the methods in - * the superclass are intended for cryptographic service providers who wish to - * supply their own implementations of message digest algorithms.</p> + * data and output a fixed-length hash value. * * @see MessageDigestSpi - * @see Provider * @since JDK 1.1 */ public abstract class MessageDigest extends MessageDigestSpi @@ -100,12 +56,11 @@ public abstract class MessageDigest extends MessageDigestSpi private byte[] lastDigest; /** - * Creates a message digest with the specified algorithm name. - * - * @param algorithm the standard name of the digest algorithm. - * See Appendix A in the Java Cryptography Architecture API - * Specification & Reference for information about standard - * algorithm names. + * Constructs a new instance of <code>MessageDigest</code> representing the + * specified algorithm. + * + * @param algorithm + * the name of the digest algorithm to use. */ protected MessageDigest(String algorithm) { @@ -114,19 +69,14 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Generates a <code>MessageDigest</code> object that implements the specified - * digest algorithm. If the default provider package provides an - * implementation of the requested digest algorithm, an instance of - * <code>MessageDigest</code> containing that implementation is returned. If - * the algorithm is not available in the default package, other packages are - * searched. - * - * @param algorithm the name of the algorithm requested. See Appendix A in the - * Java Cryptography Architecture API Specification & Reference for - * information about standard algorithm names. - * @return a Message Digest object implementing the specified algorithm. - * @throws NoSuchAlgorithmException if the algorithm is not available in the - * caller's environment. + * Returns a new instance of <code>MessageDigest</code> representing the + * specified algorithm. + * + * @param algorithm + * the name of the digest algorithm to use. + * @return a new instance representing the desired algorithm. + * @throws NoSuchAlgorithmException + * if the algorithm is not implemented by any provider. */ public static MessageDigest getInstance(String algorithm) throws NoSuchAlgorithmException @@ -148,21 +98,18 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Generates a <code>MessageDigest</code> object implementing the specified - * algorithm, as supplied from the specified provider, if such an algorithm is - * available from the provider. - * - * @param algorithm the name of the algorithm requested. See Appendix A in the - * Java Cryptography Architecture API Specification & Reference for - * information about standard algorithm names. - * @param provider the name of the provider. - * @return a Message Digest object implementing the specified algorithm. - * @throws NoSuchAlgorithmException if the algorithm is not available in the - * package supplied by the requested provider. - * @throws NoSuchProviderException if the provider is not available in the - * environment. - * @throws IllegalArgumentException if the provider name is null or empty. - * @see Provider + * Returns a new instance of <code>MessageDigest</code> representing the + * specified algorithm from a named provider. + * + * @param algorithm + * the name of the digest algorithm to use. + * @param provider + * the name of the provider to use. + * @return a new instance representing the desired algorithm. + * @throws NoSuchAlgorithmException + * if the algorithm is not implemented by the named provider. + * @throws NoSuchProviderException + * if the named provider was not found. */ public static MessageDigest getInstance(String algorithm, String provider) throws NoSuchAlgorithmException, NoSuchProviderException @@ -181,20 +128,18 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Generates a <code>MessageDigest</code> object implementing the specified - * algorithm, as supplied from the specified provider, if such an algorithm - * is available from the provider. Note: the provider doesn't have to be - * registered. - * - * @param algorithm the name of the algorithm requested. See Appendix A in - * the Java Cryptography Architecture API Specification & Reference for - * information about standard algorithm names. - * @param provider the provider. - * @return a Message Digest object implementing the specified algorithm. - * @throws NoSuchAlgorithmException if the <code>algorithm</code> is not - * available in the package supplied by the requested <code>provider</code>. - * @throws IllegalArgumentException if the <code>provider</code> is - * <code>null</code>. + * Returns a new instance of <code>MessageDigest</code> representing the + * specified algorithm from a designated {@link Provider}. + * + * @param algorithm + * the name of the digest algorithm to use. + * @param provider + * the {@link Provider} to use. + * @return a new instance representing the desired algorithm. + * @throws IllegalArgumentException + * if <code>provider</code> is <code>null</code>. + * @throws NoSuchAlgorithmException + * if the algorithm is not implemented by {@link Provider}. * @since 1.4 * @see Provider */ @@ -233,9 +178,9 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Returns the provider of this message digest object. - * - * @return the provider of this message digest object. + * Returns the {@link Provider} of this instance. + * + * @return the {@link Provider} of this instance. */ public final Provider getProvider() { @@ -243,9 +188,9 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Updates the digest using the specified byte. - * - * @param input the byte with which to update the digest. + * Updates the digest with the byte. + * + * @param input byte to update the digest with. */ public void update(byte input) { @@ -253,12 +198,15 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Updates the digest using the specified array of bytes, starting at the - * specified offset. - * - * @param input the array of bytes. - * @param offset the offset to start from in the array of bytes. - * @param len the number of bytes to use, starting at offset. + * Updates the digest with the bytes from the array starting from the + * specified offset and using the specified length of bytes. + * + * @param input + * bytes to update the digest with. + * @param offset + * the offset to start at. + * @param len + * length of the data to update with. */ public void update(byte[] input, int offset, int len) { @@ -266,9 +214,9 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Updates the digest using the specified array of bytes. - * - * @param input the array of bytes. + * Updates the digest with the bytes of an array. + * + * @param input bytes to update the digest with. */ public void update(byte[] input) { @@ -276,10 +224,9 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Completes the hash computation by performing final operations such as - * padding. The digest is reset after this call is made. - * - * @return the array of bytes for the resulting hash value. + * Computes the final digest of the stored data. + * + * @return a byte array representing the message digest. */ public byte[] digest() { @@ -287,14 +234,15 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Completes the hash computation by performing final operations such as - * padding. The digest is reset after this call is made. - * - * @param buf An output buffer for the computed digest. - * @param offset The offset into the output buffer to begin storing the digest. - * @param len The number of bytes within buf allotted for the digest. - * @return The number of bytes placed into buf. - * @throws DigestException if an error occurs. + * Computes the final digest of the stored bytes and returns the result. + * + * @param buf + * an array of bytes to store the result in. + * @param offset + * an offset to start storing the result at. + * @param len + * the length of the buffer. + * @return Returns the length of the buffer. */ public int digest(byte[] buf, int offset, int len) throws DigestException { @@ -302,13 +250,13 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Performs a final update on the digest using the specified array of bytes, - * then completes the digest computation. That is, this method first calls - * <code>update(input)</code>, passing the input array to the <code>update() - * </code> method, then calls <code>digest()</code>. - * - * @param input the input to be updated before the digest is completed. - * @return the array of bytes for the resulting hash value. + * Computes a final update using the input array of bytes, then computes a + * final digest and returns it. It calls {@link #update(byte[])} and then + * {@link #digest(byte[])}. + * + * @param input + * an array of bytes to perform final update with. + * @return a byte array representing the message digest. */ public byte[] digest(byte[] input) { @@ -317,9 +265,9 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Returns a string representation of this message digest object. - * - * @return a string representation of the object. + * Returns a string representation of this instance. + * + * @return a string representation of this instance. */ public String toString() { @@ -327,12 +275,14 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Compares two digests for equality. Does a simple byte compare. - * - * @param digesta one of the digests to compare. - * @param digestb the other digest to compare. - * @return <code>true</code> if the digests are equal, <code>false</code> - * otherwise. + * Does a simple byte comparison of the two digests. + * + * @param digesta + * first digest to compare. + * @param digestb + * second digest to compare. + * @return <code>true</code> if both are equal, <code>false</code> + * otherwise. */ public static boolean isEqual(byte[] digesta, byte[] digestb) { @@ -346,20 +296,16 @@ public abstract class MessageDigest extends MessageDigestSpi return true; } - /** Resets the digest for further use. */ + /** Resets this instance. */ public void reset() { engineReset(); } /** - * Returns a string that identifies the algorithm, independent of - * implementation details. The name should be a standard Java Security name - * (such as <code>"SHA"</code>, <code>"MD5"</code>, and so on). See Appendix - * A in the Java Cryptography Architecture API Specification & Reference - * for information about standard algorithm names. - * - * @return the name of the algorithm. + * Returns the name of message digest algorithm. + * + * @return the name of message digest algorithm. */ public final String getAlgorithm() { @@ -367,12 +313,10 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Returns the length of the digest in bytes, or <code>0</code> if this - * operation is not supported by the provider and the implementation is not - * cloneable. - * - * @return the digest length in bytes, or <code>0</code> if this operation is - * not supported by the provider and the implementation is not cloneable. + * Returns the length of the message digest. The default is zero which means + * that the concrete implementation does not implement this method. + * + * @return length of the message digest. * @since 1.2 */ public final int getDigestLength() @@ -381,11 +325,14 @@ public abstract class MessageDigest extends MessageDigestSpi } /** - * Returns a clone if the implementation is cloneable. - * - * @return a clone if the implementation is cloneable. - * @throws CloneNotSupportedException if this is called on an implementation - * that does not support {@link Cloneable}. + * Returns a clone of this instance if cloning is supported. If it does not + * then a {@link CloneNotSupportedException} is thrown. Cloning depends on + * whether the subclass {@link MessageDigestSpi} implements {@link Cloneable} + * which contains the actual implementation of the appropriate algorithm. + * + * @return a clone of this instance. + * @throws CloneNotSupportedException + * the implementation does not support cloning. */ public Object clone() throws CloneNotSupportedException { |