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diff --git a/src/proguard/shrink/ClassShrinker.java b/src/proguard/shrink/ClassShrinker.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.shrink;
+
+import proguard.classfile.*;
+import proguard.classfile.attribute.*;
+import proguard.classfile.attribute.annotation.*;
+import proguard.classfile.attribute.annotation.visitor.*;
+import proguard.classfile.attribute.visitor.AttributeVisitor;
+import proguard.classfile.constant.*;
+import proguard.classfile.editor.*;
+import proguard.classfile.util.*;
+import proguard.classfile.visitor.*;
+
+/**
+ * This ClassVisitor removes constant pool entries and class members that
+ * are not marked as being used.
+ *
+ * @see UsageMarker
+ *
+ * @author Eric Lafortune
+ */
+public class ClassShrinker
+extends      SimplifiedVisitor
+implements   ClassVisitor,
+             MemberVisitor,
+             AttributeVisitor,
+             AnnotationVisitor,
+             ElementValueVisitor
+{
+    private final UsageMarker usageMarker;
+
+    private int[] constantIndexMap = new int[ClassConstants.TYPICAL_CONSTANT_POOL_SIZE];
+
+    private final ConstantPoolRemapper constantPoolRemapper = new ConstantPoolRemapper();
+
+
+    /**
+     * Creates a new ClassShrinker.
+     * @param usageMarker the usage marker that is used to mark the classes
+     *                    and class members.
+     */
+    public ClassShrinker(UsageMarker usageMarker)
+    {
+        this.usageMarker = usageMarker;
+    }
+
+
+    // Implementations for ClassVisitor.
+
+    public void visitProgramClass(ProgramClass programClass)
+    {
+        // Shrink the arrays for constant pool, interfaces, fields, methods,
+        // and class attributes.
+        programClass.u2interfacesCount =
+            shrinkConstantIndexArray(programClass.constantPool,
+                                     programClass.u2interfaces,
+                                     programClass.u2interfacesCount);
+
+        // Shrinking the constant pool also sets up an index map.
+        programClass.u2constantPoolCount =
+            shrinkConstantPool(programClass.constantPool,
+                               programClass.u2constantPoolCount);
+
+        programClass.u2fieldsCount =
+            shrinkArray(programClass.fields,
+                        programClass.u2fieldsCount);
+
+        programClass.u2methodsCount =
+            shrinkArray(programClass.methods,
+                        programClass.u2methodsCount);
+
+        programClass.u2attributesCount =
+            shrinkArray(programClass.attributes,
+                        programClass.u2attributesCount);
+
+        // Compact the remaining fields, methods, and attributes,
+        // and remap their references to the constant pool.
+        programClass.fieldsAccept(this);
+        programClass.methodsAccept(this);
+        programClass.attributesAccept(this);
+
+        // Remap all constant pool references.
+        constantPoolRemapper.setConstantIndexMap(constantIndexMap);
+        constantPoolRemapper.visitProgramClass(programClass);
+
+        // Remove the unused interfaces from the class signature.
+        programClass.attributesAccept(new SignatureShrinker());
+
+        // Compact the extra field pointing to the subclasses of this class.
+        programClass.subClasses =
+            shrinkToNewArray(programClass.subClasses);
+    }
+
+
+    public void visitLibraryClass(LibraryClass libraryClass)
+    {
+        // Library classes are left unchanged.
+
+        // Compact the extra field pointing to the subclasses of this class.
+        libraryClass.subClasses =
+            shrinkToNewArray(libraryClass.subClasses);
+    }
+
+
+    // Implementations for MemberVisitor.
+
+    public void visitProgramMember(ProgramClass programClass, ProgramMember programMember)
+    {
+        // Shrink the attributes array.
+        programMember.u2attributesCount =
+            shrinkArray(programMember.attributes,
+                        programMember.u2attributesCount);
+
+        // Shrink any attributes.
+        programMember.attributesAccept(programClass, this);
+    }
+
+
+    // Implementations for AttributeVisitor.
+
+    public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}
+
+
+    public void visitInnerClassesAttribute(Clazz clazz, InnerClassesAttribute innerClassesAttribute)
+    {
+        // Shrink the array of InnerClassesInfo objects.
+        innerClassesAttribute.u2classesCount =
+            shrinkArray(innerClassesAttribute.classes,
+                        innerClassesAttribute.u2classesCount);
+    }
+
+
+    public void visitEnclosingMethodAttribute(Clazz clazz, EnclosingMethodAttribute enclosingMethodAttribute)
+    {
+        // Sometimes, a class is still referenced (apparently as a dummy class),
+        // but its enclosing method is not. Then remove the reference to
+        // the enclosing method.
+        // E.g. the anonymous inner class javax.swing.JList$1 is defined inside
+        // a constructor of javax.swing.JList, but it is also referenced as a
+        // dummy argument in a constructor of javax.swing.JList$ListSelectionHandler.
+        if (enclosingMethodAttribute.referencedMethod != null &&
+            !usageMarker.isUsed(enclosingMethodAttribute.referencedMethod))
+        {
+            enclosingMethodAttribute.u2nameAndTypeIndex = 0;
+
+            enclosingMethodAttribute.referencedMethod = null;
+        }
+    }
+
+
+    public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
+    {
+        // Shrink the attributes array.
+        codeAttribute.u2attributesCount =
+            shrinkArray(codeAttribute.attributes,
+                        codeAttribute.u2attributesCount);
+    }
+
+
+    public void visitAnyAnnotationsAttribute(Clazz clazz, AnnotationsAttribute annotationsAttribute)
+    {
+        // Shrink the annotations array.
+        annotationsAttribute.u2annotationsCount =
+            shrinkArray(annotationsAttribute.annotations,
+                        annotationsAttribute.u2annotationsCount);
+
+        // Shrink the annotations themselves.
+        annotationsAttribute.annotationsAccept(clazz, this);
+    }
+
+
+    public void visitAnyParameterAnnotationsAttribute(Clazz clazz, Method method, ParameterAnnotationsAttribute parameterAnnotationsAttribute)
+    {
+        // Loop over all parameters.
+        for (int parameterIndex = 0; parameterIndex < parameterAnnotationsAttribute.u2parametersCount; parameterIndex++)
+        {
+            // Shrink the parameter annotations array.
+            parameterAnnotationsAttribute.u2parameterAnnotationsCount[parameterIndex] =
+                shrinkArray(parameterAnnotationsAttribute.parameterAnnotations[parameterIndex],
+                            parameterAnnotationsAttribute.u2parameterAnnotationsCount[parameterIndex]);
+        }
+
+        // Shrink the annotations themselves.
+        parameterAnnotationsAttribute.annotationsAccept(clazz, method, this);
+    }
+
+
+    // Implementations for AnnotationVisitor.
+
+    public void visitAnnotation(Clazz clazz, Annotation annotation)
+    {
+        // Shrink the element values array.
+        annotation.u2elementValuesCount =
+            shrinkArray(annotation.elementValues,
+                        annotation.u2elementValuesCount);
+
+        // Shrink the element values themselves.
+        annotation.elementValuesAccept(clazz, this);
+    }
+
+
+    /**
+     * This AttributeVisitor updates the Utf8 constants of class signatures,
+     * removing any unused interfaces.
+     */
+    private class SignatureShrinker
+    extends       SimplifiedVisitor
+    implements    AttributeVisitor
+    {
+        public void visitAnyAttribute(Clazz clazz, Attribute attribute) {}
+
+
+        public void visitSignatureAttribute(Clazz clazz, SignatureAttribute  signatureAttribute)
+        {
+            Clazz[] referencedClasses = signatureAttribute.referencedClasses;
+            if (referencedClasses != null)
+            {
+                // Go over the generic definitions, superclass and implemented interfaces.
+                String signature = clazz.getString(signatureAttribute.u2signatureIndex);
+
+                InternalTypeEnumeration internalTypeEnumeration =
+                    new InternalTypeEnumeration(signature);
+
+                StringBuffer newSignatureBuffer = new StringBuffer();
+
+                int referencedClassIndex    = 0;
+                int newReferencedClassIndex = 0;
+
+                while (internalTypeEnumeration.hasMoreTypes())
+                {
+                    // Consider the classes referenced by this signature.
+                    String type       = internalTypeEnumeration.nextType();
+                    int    classCount = new DescriptorClassEnumeration(type).classCount();
+
+                    Clazz referencedClass = referencedClasses[referencedClassIndex];
+                    if (referencedClass == null ||
+                        usageMarker.isUsed(referencedClass))
+                    {
+                        // Append the superclass or interface.
+                        newSignatureBuffer.append(type);
+
+                        // Copy the referenced classes.
+                        for (int counter = 0; counter < classCount; counter++)
+                        {
+                            referencedClasses[newReferencedClassIndex++] =
+                                referencedClasses[referencedClassIndex++];
+                        }
+                    }
+                    else
+                    {
+                        // Skip the referenced classes.
+                        referencedClassIndex += classCount;
+                    }
+                }
+
+                if (newReferencedClassIndex < referencedClassIndex)
+                {
+                    // Update the signature.
+                    ((Utf8Constant)((ProgramClass)clazz).constantPool[signatureAttribute.u2signatureIndex]).setString(newSignatureBuffer.toString());
+
+                    // Clear the unused entries.
+                    while (newReferencedClassIndex < referencedClassIndex)
+                    {
+                        referencedClasses[newReferencedClassIndex++] = null;
+                    }
+                }
+            }
+        }
+    }
+
+
+    // Implementations for ElementValueVisitor.
+
+    public void visitAnyElementValue(Clazz clazz, Annotation annotation, ElementValue elementValue) {}
+
+
+    public void visitAnnotationElementValue(Clazz clazz, Annotation annotation, AnnotationElementValue annotationElementValue)
+    {
+        // Shrink the contained annotation.
+        annotationElementValue.annotationAccept(clazz, this);
+    }
+
+
+    public void visitArrayElementValue(Clazz clazz, Annotation annotation, ArrayElementValue arrayElementValue)
+    {
+        // Shrink the element values array.
+        arrayElementValue.u2elementValuesCount =
+            shrinkArray(arrayElementValue.elementValues,
+                        arrayElementValue.u2elementValuesCount);
+
+        // Shrink the element values themselves.
+        arrayElementValue.elementValuesAccept(clazz, annotation, this);
+    }
+
+
+    // Small utility methods.
+
+    /**
+     * Removes all entries that are not marked as being used from the given
+     * constant pool.
+     * @return the new number of entries.
+     */
+    private int shrinkConstantPool(Constant[] constantPool, int length)
+    {
+        if (constantIndexMap.length < length)
+        {
+            constantIndexMap = new int[length];
+        }
+
+        int     counter = 1;
+        boolean isUsed  = false;
+
+        // Shift the used constant pool entries together.
+        for (int index = 1; index < length; index++)
+        {
+            constantIndexMap[index] = counter;
+
+            Constant constant = constantPool[index];
+
+            // Don't update the flag if this is the second half of a long entry.
+            if (constant != null)
+            {
+                isUsed = usageMarker.isUsed(constant);
+            }
+
+            if (isUsed)
+            {
+                constantPool[counter++] = constant;
+            }
+        }
+
+        // Clear the remaining constant pool elements.
+        for (int index = counter; index < length; index++)
+        {
+            constantPool[index] = null;
+        }
+
+        return counter;
+    }
+
+
+    /**
+     * Removes all indices that point to unused constant pool entries
+     * from the given array.
+     * @return the new number of indices.
+     */
+    private int shrinkConstantIndexArray(Constant[] constantPool, int[] array, int length)
+    {
+        int counter = 0;
+
+        // Shift the used objects together.
+        for (int index = 0; index < length; index++)
+        {
+            if (usageMarker.isUsed(constantPool[array[index]]))
+            {
+                array[counter++] = array[index];
+            }
+        }
+
+        // Clear the remaining array elements.
+        for (int index = counter; index < length; index++)
+        {
+            array[index] = 0;
+        }
+
+        return counter;
+    }
+
+
+    /**
+     * Removes all Clazz objects that are not marked as being used
+     * from the given array and returns the remaining objects in a an array
+     * of the right size.
+     * @return the new array.
+     */
+    private Clazz[] shrinkToNewArray(Clazz[] array)
+    {
+        if (array == null)
+        {
+            return null;
+        }
+
+        // Shrink the given array in-place.
+        int length = shrinkArray(array, array.length);
+        if (length == 0)
+        {
+            return null;
+        }
+
+        // Return immediately if the array is of right size already.
+        if (length == array.length)
+        {
+            return array;
+        }
+
+        // Copy the remaining elements into a new array of the right size.
+        Clazz[] newArray = new Clazz[length];
+        System.arraycopy(array, 0, newArray, 0, length);
+        return newArray;
+    }
+
+
+    /**
+     * Removes all VisitorAccepter objects that are not marked as being used
+     * from the given array.
+     * @return the new number of VisitorAccepter objects.
+     */
+    private int shrinkArray(VisitorAccepter[] array, int length)
+    {
+        int counter = 0;
+
+        // Shift the used objects together.
+        for (int index = 0; index < length; index++)
+        {
+            if (usageMarker.isUsed(array[index]))
+            {
+                array[counter++] = array[index];
+            }
+        }
+
+        // Clear the remaining array elements.
+        for (int index = counter; index < length; index++)
+        {
+            array[index] = null;
+        }
+
+        return counter;
+    }
+}