1 files changed, 72 insertions, 0 deletions
diff --git a/src/proguard/classfile/visitor/ClassVersionFilter.java b/src/proguard/classfile/visitor/ClassVersionFilter.java
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+++ b/src/proguard/classfile/visitor/ClassVersionFilter.java
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+/*
+ * ProGuard -- shrinking, optimization, obfuscation, and preverification
+ *             of Java bytecode.
+ *
+ * Copyright (c) 2002-2009 Eric Lafortune (eric@graphics.cornell.edu)
+ *
+ * This program 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 of the License, or (at your option)
+ * any later version.
+ *
+ * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+package proguard.classfile.visitor;
+
+import proguard.classfile.*;
+
+/**
+ * This <code>ClassVisitor</code> delegates its visits to program classes to
+ * another given <code>ClassVisitor</code>, but only when the class version
+ * number of the visited program class lies in a given range.
+ *
+ * @author Eric Lafortune
+ */
+public class ClassVersionFilter implements ClassVisitor
+{
+    private final int          minimumClassVersion;
+    private final int          maximumClassVersion;
+    private final ClassVisitor classVisitor;
+
+
+    /**
+     * Creates a new ClassVersionFilter.
+     * @param minimumClassVersion the minimum class version number.
+     * @param maximumClassVersion the maximum class version number.
+     * @param classVisitor        the <code>ClassVisitor</code> to which visits
+     *                            will be delegated.
+     */
+    public ClassVersionFilter(int          minimumClassVersion,
+                              int          maximumClassVersion,
+                              ClassVisitor classVisitor)
+    {
+        this.minimumClassVersion = minimumClassVersion;
+        this.maximumClassVersion = maximumClassVersion;
+        this.classVisitor        = classVisitor;
+    }
+
+
+    // Implementations for ClassVisitor.
+
+    public void visitProgramClass(ProgramClass programClass)
+    {
+        if (programClass.u4version >= minimumClassVersion &&
+            programClass.u4version <= maximumClassVersion)
+        {
+            classVisitor.visitProgramClass(programClass);
+        }
+    }
+
+
+    public void visitLibraryClass(LibraryClass libraryClass)
+    {
+        // Library classes don't have version numbers.
+    }
+}