[RFA/JDWP] utility class: Signature

[Keith Seitz <keiths at redhat dot com>]

Hi,

The attached patch is the entire gnu.classpath.jdwp.util package. It
currently contains one class, Signature, which computes method and class
signatures (a la "Ljava/lang/String;").

Much of the code in this class comes from Tom Tromey.

Keith

ChangeLog
2005-06-06  Keith Seitz  <keiths@redhat.com>

	* gnu/classpath/jdwp/util/Signature.java: New file.


Index: libjava/gnu/classpath/jdwp/util/Signature.java
===================================================================
RCS file: libjava/gnu/classpath/jdwp/util/Signature.java
diff -N libjava/gnu/classpath/jdwp/util/Signature.java
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ libjava/gnu/classpath/jdwp/util/Signature.java	6 Jun 2005 22:38:21 -0000
@@ -0,0 +1,135 @@
+/* Signature.java -- utility class to compute class and method signatures
+   Copyright (C) 2005 Free Software Foundation
+
+This file is part of GNU Classpath.
+
+GNU Classpath is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+GNU Classpath is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with GNU Classpath; see the file COPYING.  If not, write to the
+Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+02111-1307 USA.
+
+Linking this library statically or dynamically with other modules is
+making a combined work based on this library.  Thus, the terms and
+conditions of the GNU General Public License cover the whole
+combination.
+
+As a special exception, the copyright holders of this library give you
+permission to link this library with independent modules to produce an
+executable, regardless of the license terms of these independent
+modules, and to copy and distribute the resulting executable under
+terms of your choice, provided that you also meet, for each linked
+terms of your choice, provided that you also meet, for each linked
+independent module, the terms and conditions of the license of that
+module.  An independent module is a module which is not derived from
+or based on this library.  If you modify this library, you may extend
+this exception to your version of the library, but you are not
+obligated to do so.  If you do not wish to do so, delete this
+exception statement from your version. */
+
+
+package gnu.classpath.jdwp.util;
+
+import java.lang.reflect.Method;
+
+/**
+ * A class to compute class and method signatures.
+ *
+ * @author Tom Tromey  <tromey@redhat.com>
+ * @author Keith Seitz  <keiths@redhat.com>
+ */
+public class Signature
+{
+  /**
+   * Computes the class signature, i.e., java.lang.String.class
+   * returns "Ljava/lang/String;".
+   *
+   * @param theClass  the class for which to compute the signature
+   * @return          the class's type signature
+   */
+  public static String computeClassSignature (Class theClass)
+  {
+    StringBuffer sb = new StringBuffer ();
+    _addToSignature (sb, theClass);
+    return sb.toString ();
+  }
+
+  /**
+   * Computes the method signature, i.e., java.lang.String.split (String, int)
+   * returns "(Ljava/lang/String;I)[Ljava/lang/String;"
+   *
+   * @param method  the method for which to compute the signature
+   * @return        the method's type signature
+   */
+  public static String computeMethodSignature (Method method)
+  {
+    return _computeSignature (method.getReturnType (),
+			      method.getParameterTypes ());
+  }
+
+  private static String _computeSignature (Class returnType,
+					   Class[] paramTypes)
+  {
+    StringBuffer sb = new StringBuffer ("(");
+    if (paramTypes != null)
+      {
+	for (int i = 0; i < paramTypes.length; ++i)
+	  _addToSignature (sb, paramTypes[i]);
+      }
+    sb.append (")");
+    _addToSignature (sb, returnType);
+    return sb.toString();
+  }
+
+  private static void _addToSignature (StringBuffer sb, Class k)
+  {
+    // For some reason there's no easy way to get the signature of a
+    // class.
+    if (k.isPrimitive ())
+      {
+        if (k == void.class)
+          sb.append('V');
+        else if (k == boolean.class)
+          sb.append('Z');
+        else if (k == byte.class)
+          sb.append('B');
+        else if (k == char.class)
+          sb.append('C');
+        else if (k == short.class)
+          sb.append('S');
+        else if (k == int.class)
+          sb.append('I');
+        else if (k == float.class)
+          sb.append('F');
+        else if (k == double.class)
+          sb.append('D');
+        else if (k == long.class)
+          sb.append('J');
+        return;
+      }
+    
+    String name = k.getName ();
+    int len = name.length ();
+    sb.ensureCapacity (len);
+    if (! k.isArray ())
+      sb.append('L');
+    for (int i = 0; i < len; ++i)
+      {
+	char c = name.charAt (i);
+	if (c == '.')
+	  c = '/';
+	sb.append (c);
+      }
+    if (! k.isArray ())
+      sb.append(';');
+  }
+}