[Clirr-devel] CVS: clirr/src/java/net/sf/clirr/checks ClassModifierCheck.java,1.9,1.10

[Simon K. <s_k...@us...>]

Update of /cvsroot/clirr/clirr/src/java/net/sf/clirr/checks
In directory sc8-pr-cvs1.sourceforge.net:/tmp/cvs-serv14085

Modified Files:
	ClassModifierCheck.java 
Log Message:
Implemented TODO item: it is not an error to add final to a class if that
class previously had no public or protected constructors.


Index: ClassModifierCheck.java
===================================================================
RCS file: /cvsroot/clirr/clirr/src/java/net/sf/clirr/checks/ClassModifierCheck.java,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -r1.9 -r1.10
--- ClassModifierCheck.java	18 Jun 2004 06:52:10 -0000	1.9
+++ ClassModifierCheck.java	21 Jun 2004 07:26:58 -0000	1.10
@@ -23,7 +23,11 @@
 import net.sf.clirr.framework.AbstractDiffReporter;
 import net.sf.clirr.framework.ApiDiffDispatcher;
 import net.sf.clirr.framework.ClassChangeCheck;
+import net.sf.clirr.framework.CheckerException;
+import net.sf.clirr.event.ScopeSelector;
+
 import org.apache.bcel.classfile.JavaClass;
+import org.apache.bcel.classfile.Method;
 
 /**
  * Detects changes in class modifiers (abstract, final).
@@ -46,6 +50,25 @@
     /** {@inheritDoc} */
     public boolean check(JavaClass compatBaseLine, JavaClass currentVersion)
     {
+        final String className = compatBaseLine.getClassName();
+
+        try
+        {
+            ScopeSelector.Scope currentScope = ScopeSelector.getClassScope(currentVersion);
+            if (currentScope == ScopeSelector.SCOPE_PRIVATE)
+            {
+                // for private classes, we don't care if they are now final,
+                // or now abstract, or now an interface.
+                return true;
+            }
+        }
+        catch (CheckerException ex)
+        {
+            log("Unable to determine whether class is private",
+                    Severity.ERROR, className, null, null);
+            return true;
+        }
+
         final boolean currentIsFinal = currentVersion.isFinal();
         final boolean compatIsFinal = compatBaseLine.isFinal();
         final boolean currentIsAbstract = currentVersion.isAbstract();
@@ -53,13 +76,6 @@
         final boolean currentIsInterface = currentVersion.isInterface();
         final boolean compatIsInterface = compatBaseLine.isInterface();
 
-        final String className = compatBaseLine.getClassName();
-
-        // TODO: There are cases when nonfinal classes are effectively final
-        // because they do not have public or protected ctors. For such
-        // classes we should not emit errors when a final modifier is
-        // introduced.
-
         if (compatIsFinal && !currentIsFinal)
         {
             log("Removed final modifier in class " + className,
@@ -67,8 +83,17 @@
         }
         else if (!compatIsFinal && currentIsFinal)
         {
-            log("Added final modifier in class " + className,
-                    Severity.ERROR, className, null, null);
+            if (isEffectivelyFinal(compatBaseLine))
+            {
+                log("Added final modifier in class " + className
+                        + " (but class was effectively final anyway)",
+                        Severity.INFO, className, null, null);
+                }
+            else
+            {
+                log("Added final modifier in class " + className,
+                        Severity.ERROR, className, null, null);
+            }
         }
 
         // interfaces are always abstract, don't report gender change here
@@ -86,4 +111,36 @@
         return true;
     }
 
+    /**
+     * There are cases where nonfinal classes are effectively final
+     * because they do not have public or protected ctors. For such
+     * classes we should not emit errors when a final modifier is
+     * introduced.
+     */
+    private boolean isEffectivelyFinal(JavaClass clazz)
+    {
+        if (clazz.isFinal())
+        {
+            return true;
+        }
+
+        // iterate over all constructors, and detect whether any are
+        // public or protected. If so, return false.
+        Method[] methods = clazz.getMethods();
+        for (int i = 0; i < methods.length; ++i)
+        {
+            Method method = methods[i];
+            final String methodName = method.getName();
+            if (methodName.equals("<init>"))
+            {
+                if (method.isPublic() || method.isProtected())
+                {
+                    return false;
+                }
+            }
+        }
+
+        // no public or protected constructor found
+        return true;
+    }
 }