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diff --git a/src/proguard/classfile/editor/Utf8Shrinker.java b/src/proguard/classfile/editor/Utf8Shrinker.java
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+++ b/src/proguard/classfile/editor/Utf8Shrinker.java
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+/*
+ * ProGuard -- shrinking, optimization, obfuscation, and preverification
+ *             of Java bytecode.
+ *
+ * Copyright (c) 2002-2013 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.editor;
+
+import proguard.classfile.*;
+import proguard.classfile.attribute.*;
+import proguard.classfile.attribute.annotation.*;
+import proguard.classfile.attribute.annotation.visitor.*;
+import proguard.classfile.attribute.preverification.*;
+import proguard.classfile.attribute.visitor.*;
+import proguard.classfile.constant.*;
+import proguard.classfile.constant.visitor.ConstantVisitor;
+import proguard.classfile.editor.ConstantPoolRemapper;
+import proguard.classfile.util.SimplifiedVisitor;
+import proguard.classfile.visitor.*;
+
+import java.util.Arrays;
+
+
+/**
+ * This ClassVisitor removes UTF-8 constant pool entries that are not used.
+ *
+ * @author Eric Lafortune
+ */
+public class Utf8Shrinker
+extends      SimplifiedVisitor
+implements   ClassVisitor,
+             MemberVisitor,
+             ConstantVisitor,
+             AttributeVisitor,
+             InnerClassesInfoVisitor,
+             LocalVariableInfoVisitor,
+             LocalVariableTypeInfoVisitor,
+             AnnotationVisitor,
+             ElementValueVisitor
+{
+    // A visitor info flag to indicate the UTF-8 constant pool entry is being used.
+    private static final Object USED = new Object();
+
+    private       int[]                constantIndexMap     = new int[ClassConstants.TYPICAL_CONSTANT_POOL_SIZE];
+    private final ConstantPoolRemapper constantPoolRemapper = new ConstantPoolRemapper();
+
+
+    // Implementations for ClassVisitor.
+
+    public void visitProgramClass(ProgramClass programClass)
+    {
+        // Mark the UTF-8 entries referenced by the other constant pool entries.
+        programClass.constantPoolEntriesAccept(this);
+
+        // Mark the UTF-8 entries referenced by the fields and methods.
+        programClass.fieldsAccept(this);
+        programClass.methodsAccept(this);
+
+        // Mark the UTF-8 entries referenced by the attributes.
+        programClass.attributesAccept(this);
+
+        // Shift the used constant pool entries together, filling out the
+        // index map.
+        int newConstantPoolCount =
+            shrinkConstantPool(programClass.constantPool,
+                               programClass.u2constantPoolCount);
+
+        // Remap the references to the constant pool if it has shrunk.
+        if (newConstantPoolCount < programClass.u2constantPoolCount)
+        {
+            programClass.u2constantPoolCount = newConstantPoolCount;
+
+            // Remap all constant pool references.
+            constantPoolRemapper.setConstantIndexMap(constantIndexMap);
+            constantPoolRemapper.visitProgramClass(programClass);
+        }
+    }
+
+
+    // Implementations for MemberVisitor.
+
+    public void visitProgramMember(ProgramClass programClass, ProgramMember programMember)
+    {
+        // Mark the name and descriptor UTF-8 entries.
+        markCpUtf8Entry(programClass, programMember.u2nameIndex);
+        markCpUtf8Entry(programClass, programMember.u2descriptorIndex);
+
+        // Mark the UTF-8 entries referenced by the attributes.
+        programMember.attributesAccept(programClass, this);
+    }
+
+
+    // Implementations for ConstantVisitor.
+
+    public void visitAnyConstant(Clazz clazz, Constant constant) {}
+
+
+    public void visitStringConstant(Clazz clazz, StringConstant stringConstant)
+    {
+        markCpUtf8Entry(clazz, stringConstant.u2stringIndex);
+    }
+
+
+    public void visitClassConstant(Clazz clazz, ClassConstant classConstant)
+    {
+        markCpUtf8Entry(clazz, classConstant.u2nameIndex);
+    }
+
+
+    public void visitNameAndTypeConstant(Clazz clazz, NameAndTypeConstant nameAndTypeConstant)
+    {
+        markCpUtf8Entry(clazz, nameAndTypeConstant.u2nameIndex);
+        markCpUtf8Entry(clazz, nameAndTypeConstant.u2descriptorIndex);
+    }
+
+
+    // Implementations for AttributeVisitor.
+
+    public void visitUnknownAttribute(Clazz clazz, UnknownAttribute unknownAttribute)
+    {
+        // This is the best we can do for unknown attributes.
+        markCpUtf8Entry(clazz, unknownAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitSourceFileAttribute(Clazz clazz, SourceFileAttribute sourceFileAttribute)
+    {
+        markCpUtf8Entry(clazz, sourceFileAttribute.u2attributeNameIndex);
+
+        markCpUtf8Entry(clazz, sourceFileAttribute.u2sourceFileIndex);
+    }
+
+
+    public void visitSourceDirAttribute(Clazz clazz, SourceDirAttribute sourceDirAttribute)
+    {
+        markCpUtf8Entry(clazz, sourceDirAttribute.u2attributeNameIndex);
+
+        markCpUtf8Entry(clazz, sourceDirAttribute.u2sourceDirIndex);
+    }
+
+
+    public void visitInnerClassesAttribute(Clazz clazz, InnerClassesAttribute innerClassesAttribute)
+    {
+        markCpUtf8Entry(clazz, innerClassesAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the inner classes.
+        innerClassesAttribute.innerClassEntriesAccept(clazz, this);
+    }
+
+
+    public void visitEnclosingMethodAttribute(Clazz clazz, EnclosingMethodAttribute enclosingMethodAttribute)
+    {
+        markCpUtf8Entry(clazz, enclosingMethodAttribute.u2attributeNameIndex);
+
+        // These entries have already been marked in the constant pool.
+        //clazz.constantPoolEntryAccept(this, enclosingMethodAttribute.u2classIndex);
+        //clazz.constantPoolEntryAccept(this, enclosingMethodAttribute.u2nameAndTypeIndex);
+    }
+
+
+    public void visitDeprecatedAttribute(Clazz clazz, DeprecatedAttribute deprecatedAttribute)
+    {
+        markCpUtf8Entry(clazz, deprecatedAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitSyntheticAttribute(Clazz clazz, SyntheticAttribute syntheticAttribute)
+    {
+        markCpUtf8Entry(clazz, syntheticAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitSignatureAttribute(Clazz clazz, SignatureAttribute signatureAttribute)
+    {
+        markCpUtf8Entry(clazz, signatureAttribute.u2attributeNameIndex);
+
+        markCpUtf8Entry(clazz, signatureAttribute.u2signatureIndex);
+    }
+
+
+    public void visitConstantValueAttribute(Clazz clazz, Field field, ConstantValueAttribute constantValueAttribute)
+    {
+        markCpUtf8Entry(clazz, constantValueAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitExceptionsAttribute(Clazz clazz, Method method, ExceptionsAttribute exceptionsAttribute)
+    {
+        markCpUtf8Entry(clazz, exceptionsAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitCodeAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute)
+    {
+        markCpUtf8Entry(clazz, codeAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the attributes.
+        codeAttribute.attributesAccept(clazz, method, this);
+    }
+
+
+    public void visitStackMapAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute, StackMapAttribute stackMapAttribute)
+    {
+        markCpUtf8Entry(clazz, stackMapAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitStackMapTableAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute, StackMapTableAttribute stackMapTableAttribute)
+    {
+        markCpUtf8Entry(clazz, stackMapTableAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitLineNumberTableAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute, LineNumberTableAttribute lineNumberTableAttribute)
+    {
+        markCpUtf8Entry(clazz, lineNumberTableAttribute.u2attributeNameIndex);
+    }
+
+
+    public void visitLocalVariableTableAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute, LocalVariableTableAttribute localVariableTableAttribute)
+    {
+        markCpUtf8Entry(clazz, localVariableTableAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the local variables.
+        localVariableTableAttribute.localVariablesAccept(clazz, method, codeAttribute, this);
+    }
+
+
+    public void visitLocalVariableTypeTableAttribute(Clazz clazz, Method method, CodeAttribute codeAttribute, LocalVariableTypeTableAttribute localVariableTypeTableAttribute)
+    {
+        markCpUtf8Entry(clazz, localVariableTypeTableAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the local variable types.
+        localVariableTypeTableAttribute.localVariablesAccept(clazz, method, codeAttribute, this);
+    }
+
+
+    public void visitAnyAnnotationsAttribute(Clazz clazz, AnnotationsAttribute annotationsAttribute)
+    {
+        markCpUtf8Entry(clazz, annotationsAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the annotations.
+        annotationsAttribute.annotationsAccept(clazz, this);
+    }
+
+
+    public void visitAnyParameterAnnotationsAttribute(Clazz clazz, Method method, ParameterAnnotationsAttribute parameterAnnotationsAttribute)
+    {
+        markCpUtf8Entry(clazz, parameterAnnotationsAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the annotations.
+        parameterAnnotationsAttribute.annotationsAccept(clazz, method, this);
+    }
+
+
+    public void visitAnnotationDefaultAttribute(Clazz clazz, Method method, AnnotationDefaultAttribute annotationDefaultAttribute)
+    {
+        markCpUtf8Entry(clazz, annotationDefaultAttribute.u2attributeNameIndex);
+
+        // Mark the UTF-8 entries referenced by the element value.
+        annotationDefaultAttribute.defaultValueAccept(clazz, this);
+    }
+
+
+    // Implementations for InnerClassesInfoVisitor.
+
+    public void visitInnerClassesInfo(Clazz clazz, InnerClassesInfo innerClassesInfo)
+    {
+        if (innerClassesInfo.u2innerNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, innerClassesInfo.u2innerNameIndex);
+        }
+    }
+
+
+    // Implementations for LocalVariableInfoVisitor.
+
+    public void visitLocalVariableInfo(Clazz clazz, Method method, CodeAttribute codeAttribute, LocalVariableInfo localVariableInfo)
+    {
+        markCpUtf8Entry(clazz, localVariableInfo.u2nameIndex);
+        markCpUtf8Entry(clazz, localVariableInfo.u2descriptorIndex);
+    }
+
+
+    // Implementations for LocalVariableTypeInfoVisitor.
+
+    public void visitLocalVariableTypeInfo(Clazz clazz, Method method, CodeAttribute codeAttribute, LocalVariableTypeInfo localVariableTypeInfo)
+    {
+        markCpUtf8Entry(clazz, localVariableTypeInfo.u2nameIndex);
+        markCpUtf8Entry(clazz, localVariableTypeInfo.u2signatureIndex);
+    }
+
+
+    // Implementations for AnnotationVisitor.
+
+    public void visitAnnotation(Clazz clazz, Annotation annotation)
+    {
+        markCpUtf8Entry(clazz, annotation.u2typeIndex);
+
+        // Mark the UTF-8 entries referenced by the element values.
+        annotation.elementValuesAccept(clazz, this);
+    }
+
+
+    // Implementations for ElementValueVisitor.
+
+    public void visitConstantElementValue(Clazz clazz, Annotation annotation, ConstantElementValue constantElementValue)
+    {
+        if (constantElementValue.u2elementNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, constantElementValue.u2elementNameIndex);
+        }
+
+        // Only the string constant element value refers to a UTF-8 entry.
+        if (constantElementValue.u1tag == ClassConstants.ELEMENT_VALUE_STRING_CONSTANT)
+        {
+            markCpUtf8Entry(clazz, constantElementValue.u2constantValueIndex);
+        }
+    }
+
+
+    public void visitEnumConstantElementValue(Clazz clazz, Annotation annotation, EnumConstantElementValue enumConstantElementValue)
+    {
+        if (enumConstantElementValue.u2elementNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, enumConstantElementValue.u2elementNameIndex);
+        }
+
+        markCpUtf8Entry(clazz, enumConstantElementValue.u2typeNameIndex);
+        markCpUtf8Entry(clazz, enumConstantElementValue.u2constantNameIndex);
+    }
+
+
+    public void visitClassElementValue(Clazz clazz, Annotation annotation, ClassElementValue classElementValue)
+    {
+        if (classElementValue.u2elementNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, classElementValue.u2elementNameIndex);
+        }
+
+        markCpUtf8Entry(clazz, classElementValue.u2classInfoIndex);
+    }
+
+
+    public void visitAnnotationElementValue(Clazz clazz, Annotation annotation, AnnotationElementValue annotationElementValue)
+    {
+        if (annotationElementValue.u2elementNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, annotationElementValue.u2elementNameIndex);
+        }
+
+        // Mark the UTF-8 entries referenced by the annotation.
+        annotationElementValue.annotationAccept(clazz, this);
+    }
+
+
+    public void visitArrayElementValue(Clazz clazz, Annotation annotation, ArrayElementValue arrayElementValue)
+    {
+        if (arrayElementValue.u2elementNameIndex != 0)
+        {
+            markCpUtf8Entry(clazz, arrayElementValue.u2elementNameIndex);
+        }
+
+        // Mark the UTF-8 entries referenced by the element values.
+        arrayElementValue.elementValuesAccept(clazz, annotation, this);
+    }
+
+
+    // Small utility methods.
+
+    /**
+     * Marks the given UTF-8 constant pool entry of the given class.
+     */
+    private void markCpUtf8Entry(Clazz clazz, int index)
+    {
+         markAsUsed((Utf8Constant)((ProgramClass)clazz).getConstant(index));
+    }
+
+
+    /**
+     * Marks the given VisitorAccepter as being used.
+     * In this context, the VisitorAccepter will be a Utf8Constant object.
+     */
+    private void markAsUsed(VisitorAccepter visitorAccepter)
+    {
+        visitorAccepter.setVisitorInfo(USED);
+    }
+
+
+    /**
+     * Returns whether the given VisitorAccepter has been marked as being used.
+     * In this context, the VisitorAccepter will be a Utf8Constant object.
+     */
+    private boolean isUsed(VisitorAccepter visitorAccepter)
+    {
+        return visitorAccepter.getVisitorInfo() == USED;
+    }
+
+
+    /**
+     * Removes all UTF-8 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)
+    {
+        // Create a new index map, if necessary.
+        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 = constant.getTag() != ClassConstants.CONSTANT_Utf8 ||
+                         isUsed(constant);
+            }
+
+            if (isUsed)
+            {
+                constantPool[counter++] = constant;
+            }
+        }
+
+        // Clear the remaining constant pool elements.
+        Arrays.fill(constantPool, counter, length, null);
+
+        return counter;
+    }
+}