Merged gcj-eclipse branch to trunk.

From-SVN: r120621

libjava/classpath/java/security/SecureRandom.java

@@ -45,6 +45,7 @@ import gnu.java.security.jce.prng.Sha160RandomSpi;
 
 import java.io.IOException;
 import java.io.InputStream;
+import java.lang.reflect.InvocationTargetException;
 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Enumeration;
@@ -187,101 +188,106 @@ public class SecureRandom extends Random
     this.algorithm = algorithm;
   }
 
-  // Class methods.
-  // ------------------------------------------------------------------------
-
   /**
-   * Returns an instance of a SecureRandom. It creates the class from
-   * the first provider that implements it.
-   *
+   * Returns an instance of a <code>SecureRandom</code> from the first provider
+   * that implements it.
+   * 
    * @param algorithm The algorithm name.
-   * @return A new SecureRandom implementing the given algorithm.
-   * @throws NoSuchAlgorithmException If no installed provider implements
-   *         the given algorithm.
+   * @return A new <code>SecureRandom</code> implementing the given algorithm.
+   * @throws NoSuchAlgorithmException If no installed provider implements the
+   *           given algorithm.
+   * @throws IllegalArgumentException if <code>algorithm</code> is
+   *           <code>null</code> or is an empty string.
    */
   public static SecureRandom getInstance(String algorithm)
-    throws NoSuchAlgorithmException
+      throws NoSuchAlgorithmException
   {
     Provider[] p = Security.getProviders();
-    
+    NoSuchAlgorithmException lastException = null;
     for (int i = 0; i < p.length; i++)
-      {
-        try
-          {
-            return getInstance(algorithm, p[i]);
-          }
-        catch (NoSuchAlgorithmException e)
-          {
-	    // Ignore.
-          }
-      }
-
-    // None found.
+      try
+        {
+          return getInstance(algorithm, p[i]);
+        }
+      catch (NoSuchAlgorithmException x)
+        {
+          lastException = x;
+        }
+    if (lastException != null)
+      throw lastException;
     throw new NoSuchAlgorithmException(algorithm);
   }
 
   /**
-   * Returns an instance of a SecureRandom. It creates the class
-   * for the specified algorithm from the named provider.
-   *
+   * Returns an instance of a <code>SecureRandom</code> for the specified
+   * algorithm from the named provider.
+   * 
    * @param algorithm The algorithm name.
-   * @param provider  The provider name.
-   * @return A new SecureRandom implementing the chosen algorithm.
+   * @param provider The provider name.
+   * @return A new <code>SecureRandom</code> implementing the chosen
+   *         algorithm.
    * @throws NoSuchAlgorithmException If the named provider does not implement
-   *         the algorithm, or if the implementation cannot be
-   *         instantiated.
-   * @throws NoSuchProviderException If no provider named
-   *         <code>provider</code> is currently installed.
-   * @throws IllegalArgumentException If <code>provider</code> is null
-   *         or is empty.
+   *           the algorithm, or if the implementation cannot be instantiated.
+   * @throws NoSuchProviderException If no provider named <code>provider</code>
+   *           is currently installed.
+   * @throws IllegalArgumentException if either <code>algorithm</code> or
+   *           <code>provider</code> is <code>null</code> or empty.
    */
   public static SecureRandom getInstance(String algorithm, String provider)
-  throws NoSuchAlgorithmException, NoSuchProviderException
+      throws NoSuchAlgorithmException, NoSuchProviderException
   {
-    if (provider == null || provider.length() == 0)
-      throw new IllegalArgumentException("Illegal provider");
-
+    if (provider == null)
+      throw new IllegalArgumentException("provider MUST NOT be null");
+    provider = provider.trim();
+    if (provider.length() == 0)
+      throw new IllegalArgumentException("provider MUST NOT be empty");
     Provider p = Security.getProvider(provider);
     if (p == null)
       throw new NoSuchProviderException(provider);
-    
     return getInstance(algorithm, p);
   }
 
   /**
-   * Returns an instance of a SecureRandom. It creates the class for
-   * the specified algorithm from the given provider.
-   *
-   * @param algorithm The SecureRandom algorithm to create.
-   * @param provider  The provider to get the instance from.
-   * @throws NoSuchAlgorithmException If the algorithm cannot be found, or
-   *         if the class cannot be instantiated.
-   * @throws IllegalArgumentException If <code>provider</code> is null.
+   * Returns an instance of a <code>SecureRandom</code> for the specified
+   * algorithm from the given provider.
+   * 
+   * @param algorithm The <code>SecureRandom</code> algorithm to create.
+   * @param provider The provider to use.
+   * @throws NoSuchAlgorithmException If the algorithm cannot be found, or if
+   *           the class cannot be instantiated.
+   * @throws IllegalArgumentException if either <code>algorithm</code> or
+   *           <code>provider</code> is <code>null</code>, or if
+   *           <code>algorithm</code> is an empty string.
    */
   public static SecureRandom getInstance(String algorithm, Provider provider)
-  throws NoSuchAlgorithmException
+      throws NoSuchAlgorithmException
   {
-    if (provider == null)
-      throw new IllegalArgumentException("Illegal provider");
+    StringBuilder sb = new StringBuilder("SecureRandom for algorithm [")
+        .append(algorithm).append("] from provider[")
+        .append(provider).append("] could not be created");
+    Throwable cause;
     try
       {
-        return new SecureRandom((SecureRandomSpi)
-          Engine.getInstance(SECURE_RANDOM, algorithm, provider),
-          provider, algorithm);
+        Object spi = Engine.getInstance(SECURE_RANDOM, algorithm, provider);
+        return new SecureRandom((SecureRandomSpi) spi, provider, algorithm);
       }
-    catch (java.lang.reflect.InvocationTargetException ite)
+    catch (InvocationTargetException x)
       {
-	throw new NoSuchAlgorithmException(algorithm);
+        cause = x.getCause();
+        if (cause instanceof NoSuchAlgorithmException)
+          throw (NoSuchAlgorithmException) cause;
+        if (cause == null)
+          cause = x;
       }
-    catch (ClassCastException cce)
+    catch (ClassCastException x)
       {
-        throw new NoSuchAlgorithmException(algorithm);
+        cause = x;
       }
+    NoSuchAlgorithmException x = new NoSuchAlgorithmException(sb.toString());
+    x.initCause(cause);
+    throw x;
   }
 
-  // Instance methods.
-  // ------------------------------------------------------------------------
-
   /**
      Returns the provider being used by the current SecureRandom class.